Population Dynamics of Bull Trout and Spring Chinook Salmon at ...

Population Dynamics of Bull Trout and Spring ChinookSalmon at the Carmen-Smith Hydroelectric Project,Upper McKenzie River Basin, OregonFINAL REPORTPrepared forEugene Water & Electric BoardEugene, OregonPrepared byStillwater SciencesArcata, CaliforniaMarch 2006

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPopulation Dynamics of Bull Troutand Spring Chinook Salmonat the Carmen-Smith Hydroelectric Project,Upper McKenzie River Basin, OregonExecutive SummaryIntroductionThe Carmen-Smith Hydroelectric Project (Project) (FERC No. 2242) is a 114.5-megawatt facilityowned and operated by the Eugene Water & Electric Board (EWEB). The Project’s existinglicense, issued by the Federal Energy Regulatory Commission (FERC), expires on 30 November2008. To obtain a new license for operating the Project, EWEB prepared and distributed anInitial Consultation Package (ICP) (EWEB 2003). Following issuance of the ICP, publicmeetings and study planning sessions were held in Fall 2003 to discuss the Project’s operationsand potential environmental effects. An Aquatics Technical Subgroup (ATS) was formed andworked together to develop a study plan for the Population Dynamics of Bull Trout and SpringChinook Salmon study (Stillwater Sciences 2004a). Periodic Updates (communication to ATSmembers regarding study progress and findings) and Decision Points (points at which a formalprocess is initiated to make decisions about changes to study implementation based on newinformation) were used to inform and collaborate on decisions affecting the study. This reportdescribes the methods and results of the study. The purposes of this study are two-fold: (1) todevelop a better understanding of bull trout (Salvelinus confluentus) and spring Chinook salmon(Oncorhynchus tschawytscha) population dynamics in the Study Area, and (2) to create a tool toaid in management decisions that could improve spring Chinook salmon and bull troutpopulations affected by the Project. Outcomes of the technical studies that pertain tomanagement decisions or actions will be addressed in the License Application, due to FERC inNovember 2006.MethodsConceptual models were developed that provided a theoretical foundation for quantitativemodels, by identifying factors that limit life history stages and factors that limit the overallproduction of the populations. These factors were applied to the two quantitative populationmodels developed for the Study Area: one for bull trout and one for spring Chinook salmon. Themodels were developed in spreadsheet form using Microsoft Excel 2003®. The models followthe stock-production approach to population modeling, which is supported by a large body ofliterature spanning several decades (e.g., Paulik 1973, Moussalli and Hilborn 1986). The utilityof these models, like all models, is a function of the quality of the data that is used to populatethem, and in some cases models are best used to identify additional information needs. Thismodel however, serves as a useful and predictive tool because it is a compilation of all availabledata from recent fieldwork and the published literature, organized in a rigorous and transparentframework.The models were used to determine the factors affecting both bull trout and Chinook salmonpopulations. Project effects were considered, as were potential changes to Project facilities andoperations, habitat enhancements, and other management options that would increase productionof bull trout adults or spring Chinook salmon smolts. The intention of the models was not topredict the precise population size of any particular life-stage, but rather identify critical life-28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Boardii

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportstages, and compare relative changes in population size between alternative managementscenarios.Potential habitat enhancement and management options that were modeled include:• Increased instream flows in the lower Carmen Bypass Reach and the Smith Bypass Reach(including a scenario with hypolimnetic releases from Smith Dam)• Large woody debris enhancements in the Carmen Bypass Reach, Smith Bypass Reach, andSweetwater Creek• Increased spawning gravel availability and/or quality in Carmen Bypass Reach and SmithBypass Reach• Habitat enhancements in Trail Bridge Reservoir, the Carmen-Smith Spawning Channel, orthe mainstem McKenzie River• Changes in the hatchery rainbow trout (Oncorhynchus mykiss) stocking program• Changes in angling regulations• Fish passage facilities at Trail Bridge Dam (including various entrainment mortalityscenarios)• Fish passage facilities at Smith DamThe Study Area included: (1) the mainstem McKenzie River downstream of Trail Bridge Damand the Carmen-Smith Spawning Channel, (2) Trail Bridge Reservoir and the Carmen BypassReach upstream to Tamolitch Falls, including Kink and Sweetwater Creeks; and (3) the SmithBypass Reach, Smith Reservoir, and tributaries above Smith Reservoir, upstream to natural fishpassage barriers.ResultsBull troutBased on the conceptual and quantitative models, the bull trout population in the Study Area iscurrently limited by available habitat for subadults and adults. Available habitat is the limitationbecause so few juveniles are needed to replace mortality of subadults. Increasing the value ofevery other parameter in the model does not lead to an increase in the adult population until thecarrying capacity of the subadult/adult population is increased. The juvenile life-stage did notbegin to limit production until a subadult/adult population of 800 was reached.Management actions taken to increase spawning or rearing habitat in stream reaches or TrailBridge Reservoir are unlikely to increase the bull trout population. However, efforts to increasehabitat for subadults and adults in Trail Bridge Reservoir (e.g., increased habitat complexity)could increase carrying capacity, which would result in an increase of the adult population. Inaddition, if mortality of the adult population related to angling and poaching were reduced (e.g.,via increased law enforcement), the adult population would increase (and the population ofsubadults would decrease since they share the same habitat).Production of juvenile bull trout could be increased by large woody debris enhancements inCarmen Bypass Reach or Sweetwater Creek. Lower water temperatures in the Smith BypassReach (only possible from hypolimnetic releases from Smith Reservoir) could also increasejuvenile bull trout production. However, because subadult/adult habitat is currently limiting, noincrease in the adult population is predicted with this enhancement.If passage facilities were provided at Trail Bridge Dam, a portion of bull trout subadults andadults would likely pass downstream over the dam during the fall after spawning, and return inthe early summer. Access to the habitat in the mainstem McKenzie River downstream of Trail28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Boardiii

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportBridge Dam could increase the overall amount of adult habitat for the upstream population, andthus the population size could increase. If, however, habitat conditions for adults downstream ofTrail Bridge Dam are not as suitable as those upstream of the dam (e.g., increased anglingpressure, less food availability) or are already occupied, the health of the population upstream ofTrail Bridge Reservoir could decline (i.e., if the bull trout in Trail Bridge Reservoir are a sourcepopulation, and the population downstream of Trail Bridge Dam is stable or in decline).Although a self-sustaining population of bull trout could not be supported in Smith Reservoir,Smith Reservoir has the potential to provide subadult/adult bull trout habitat. If passage wereprovided and successful at Smith Dam, subadult and/or adult bull trout from Trail BridgeReservoir could migrate to Smith Reservoir to feed winter–summer, returning downstream tospawn during fall in Carmen Bypass Reach or Sweetwater Creek.Spring Chinook salmonBased on current population dynamics, spring Chinook salmon in the Study Area rear only brieflyin the Carmen Bypass Reach and Smith Bypass Reach before migrating downstream to TrailBridge Reservoir. Because the reservoir provides abundant rearing habitat, the modeling resultsindicate that the population is sensitive only to spawning habitat (which is not available inreservoir). As a result, the spring Chinook salmon population in the Study Area is most stronglyaffected by survival of fry, juveniles, and smolts in Trail Bridge Reservoir, and availablespawning habitat.Reducing mortality of all life-stages in Trail Bridge Reservoir would have the highest potential toincrease smolt production. In addition, increases in spawning habitat availability and/or habitatquality (e.g., through gravel augmentation, large woody debris enhancements, or increasedinstream flow) in the bypass reaches, and Smith Bypass Reach in particular, would likely increaseChinook salmon smolt production.Spring Chinook salmon in the Carmen-Smith Spawning Channel rear only briefly there beforemigrating to the mainstem McKenzie River. The spawning channel provides abundant spawninghabitat, and currently produces hundreds of thousands of emergent fry. Most of these fry rear inthe mainstem McKenzie River, such that rearing habitat quality in the mainstem stronglyinfluences subsequent potential smolt production from the spawning channel. The availablespawning habitat in the spawning channel is not currently saturated by Chinook salmon, andadditional spawning habitat is not predicted to increase production. However, overall smoltproduction could be increased by increasing habitat complexity within the spawning channel, oreven more so with by improving habitat within the mainstem McKenzie River.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Boardiv

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTABLE OF CONTENTS1 INTRODUCTION ...................................................................................................................11.1 Background .................................................................................................................... 11.2 Purpose and Relationship to Other Studies.................................................................... 21.3 Key Questions................................................................................................................ 21.4 Study Area ..................................................................................................................... 32 METHODS...............................................................................................................................42.1 Collaboration and Peer Review...................................................................................... 42.2 Conceptual Model.......................................................................................................... 62.3 Quantitative Population Models..................................................................................... 72.3.1 Model development............................................................................................... 82.3.2 Escape 5.1 superimposition sub-model............................................................... 122.3.3 Model execution.................................................................................................. 142.3.4 Evaluation of factors affecting populations ........................................................ 142.3.5 Effects of changes in Project operations on populations..................................... 153 RESULTS...............................................................................................................................163.1 Conceptual Models ...................................................................................................... 163.1.1 Bull trout ............................................................................................................. 163.1.2 Spring Chinook salmon....................................................................................... 173.2 Population Models ....................................................................................................... 183.3 Factors Affecting Population Dynamics of Bull Trout ................................................ 193.3.1 Subadult/adult population estimates ................................................................... 193.3.2 Sensitivity analysis.............................................................................................. 213.3.3 Juvenile-to-subadult recruitment......................................................................... 223.3.4 Early life-stages .................................................................................................. 243.3.5 Resiliency to disturbance .................................................................................... 253.4 Factors Affecting Population Dynamics of Spring Chinook Salmon .......................... 263.4.1 Sensitivity analysis.............................................................................................. 273.4.2 Early life-stages .................................................................................................. 293.4.3 All life-stages in Trail Bridge Reservoir............................................................. 303.4.4 Resiliency to disturbance .................................................................................... 313.5 Effects of Changes in Project Operations and/or Enhancements on Bull TroutPopulation Dynamics................................................................................................... 313.5.1 Instream flows..................................................................................................... 323.5.2 Large woody debris additions............................................................................. 343.5.3 Spawning gravel augmentation........................................................................... 343.5.4 Trail Bridge Reservoir habitat enhancements..................................................... 353.5.5 Fish Passage at Trail Bridge Dam....................................................................... 373.5.6 Fish passage at Smith Dam ................................................................................. 383.6 Effects of Changes in Project Operations and/or Enhancements on Spring ChinookSalmon......................................................................................................................... 383.6.1 Instream flows..................................................................................................... 393.6.2 Large woody debris additions............................................................................. 403.6.3 Spawning gravel augmentation........................................................................... 4128 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Boardv

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3.6.4 Trail Bridge Reservoir habitat enhancements..................................................... 413.6.5 Fish passage at Trail Bridge Dam ....................................................................... 423.6.6 Fish passage at Smith Dam ................................................................................. 433.7 Carmen-Smith Spawning Channel............................................................................... 433.7.1 Sensitivity analysis.............................................................................................. 443.7.2 Management implications................................................................................... 443.7.3 Passage at Trail Bridge Dam............................................................................... 453.8 Summary ...................................................................................................................... 453.8.1 Effects of management scenarios on population levels ...................................... 453.8.2 Key factors to protect populations ...................................................................... 474 LITERATURE CITED .........................................................................................................49TablesTable 1-1. Key questions and report sections in which they are addressed. .................................. 3Table 2-1. Participants at 18–19 January 2005 population dynamics workshop. .......................... 5Table 2-2. Life-stages modeled for bull trout and spring Chinook salmon.................................... 8Table 2-3. Life-steps modeled for bull trout and spring Chinook salmon...................................... 9Table 3-1. Population estimates for subadult/adult bull trout.. .................................................... 20Table 3-2. Bull trout subadult/adult (sexually mature and/or greater than 250 mm) populationestimates reported in the literature, and the estimated population in Trail BridgeReservoir assuming the same densities were achieved. ............................................ 21Table 3-3. Summary of sensitivity analysis on bull trout population under current conditions(subadult/adult K=111).. ........................................................................................... 22Table 3-4. Summary of sensitivity analysis on bull trout population assuming an increase insubadult/adult carrying capacity (K=500)................................................................. 22Table 3-5. Population estimates for juvenile bull trout.. .............................................................. 23Table 3-6. Resiliency of bull trout population to disturbance. ..................................................... 26Table 3-7. Summary of Chinook salmon model sensitivity analysis under current conditions.. . 28Table 3-8. Bull trout consumption of fish in Lake Billy Chinook (based on Beauchamp and VanTassell 2001) per individual and potential consumption of fish in Trail BridgeReservoir (based on Stillwater Sciences 2006a). ...................................................... 36Table 3-9. Estimated changes in Chinook salmon smolt production with increasing instreamflows in the Carmen Bypass Reach........................................................................... 39Table 3-10. Estimated changes in Chinook salmon smolt production with increasing instreamflows in the Smith Bypass Reach.............................................................................. 40Table 3-11. Summary of Chinook salmon model sensitivity analysis under current conditions atthe Carmen-Smith Spawning Channel.. .................................................................... 44Table 3-12. Summary of bull trout and Chinook salmon production in the Study Area undercurrent conditions and various management scenarios. ............................................ 46FiguresFigure 1-1. Relationship of the Population Dynamics of Bull Trout and Spring Chinook Salmonstudy to other Carmen-Smith Hydroelectric Project relicensing studies.Figure 1-2. Study Area.Figure 2-1. Egg region and defended region of a redd, as treated in the redd superimpositionmodel (Escape 5.1).Figure 2-2. Example of the bull trout population model showing the step from “stock” (1) to“production” (2).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Boardvi

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportFigure 3-1. Bull trout conceptual model upstream of Trail Bridge Dam, prior to Europeaninfluence.Figure 3-2. Conceptual model of bull trout habitat in the McKenzie River basin, prior toEuropean influence, 300 to 10,000 years before present.Figure 3-3. Bull trout conceptual model upstream of Trail Bridge Dam under current conditions.Figure 3-4. Current bull trout habitat in the McKenzie River basin.Figure 3-5. Spring Chinook salmon conceptual model in the McKenzie River, prior to Europeaninfluence.Figure 3-6. Spring Chinook salmon conceptual model in the McKenzie River under currentconditions.Figure 3-7. Schematic of bull trout population model results.Figure 3-8. Effects of superimposition on bull trout spawning in Carmen Bypass Reach, basedon suitable spawning habitat mapping at 160 cfs.Figure 3-9. Schematic of Chinook salmon population model results.Figure 3-10. Effects of increased escapement on Chinook salmon spawning in Carmen BypassReach, based on suitable spawning habitat mapping at 160 cfs.Figure 3-11. Optimal temperature for bull trout life-stages.AppendicesAppendix A: Glossary.Appendix B: Existing local information for bull trout population dynamics model.Appendix C: Existing local information for Chinook salmon population dynamics model.Appendix D: Bull trout population model parameters and values.Appendix E: Chinook salmon population model parameters and values.Appendix F: Sensitivity analysis for bull trout population dynamics model.Appendix G: Sensitivity analysis for spring Chinook salmon population dynamics model.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Boardvii

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportdiffer from naturally produced Chinook salmon (should wild fish be re-introduced above TrailBridge Dam) in their behavior and spawning success. However, NMFS considers the behaviorand success of the released hatchery fish to be an indication of how naturally-produced Chinooksalmon would respond if they had access to the same habitat (i.e., via upstream fish passagefacilities).This report describes the methods and results of the Population Dynamics of Bull Trout andSpring Chinook Salmon study. Outcomes of the technical studies that pertain to managementdecisions or actions will be addressed in the License Application, due to FERC in November2006.1.2 Purpose and Relationship to Other StudiesThe purposes of this study were to work in collaboration with the ATS: (1) to develop a betterunderstanding of bull trout and spring Chinook salmon population dynamics in the Study Area,and (2) to create a tool to aid in management decisions that could improve spring Chinook salmonand bull trout populations affected by the Project.The population models were developed to assess the Project’s effects on the patterns ofpopulation abundance and age structure of bull trout and spring Chinook salmon over time. Thestudy objectives included: (1) identifying factors most likely to affect the abundance of adults, thepopulation’s age and size structure, and the population’s resilience to disturbance; (2) identifyingpotential threats that could lead to severe population decline or extirpation; and (3) evaluatingProject effects and the effectiveness of management options designed to maintain or increase thehealth of the populations by predicting relative changes in population size between variousmanagement options.The results of several related studies (in addition to scientific literature) were used toparameterize the population models developed in this study (Figure 1-1). The Fish PopulationDistribution and Abundance study (Stillwater Sciences 2006a) delineated the areas and habitats inwhich various life-stages of spring Chinook salmon and bull trout are found, and estimated thefish densities within those habitats. The Aquatic Habitats and Instream Flows study (StillwaterSciences 2006b) provided estimates of the amount of habitat for various life-stages and howhabitat changed with flow. The Fish Entrainment study provided estimated rates of entrainmentmortality for bull trout and spring Chinook salmon that exit the Trail Bridge Reservoir via theturbine intake and the spillway, and the Water Quality study provided additional information onwater temperatures in the Study Area (Stillwater Sciences 2006c and 2006d). The FlowFluctuations and Stranding study (Stillwater Sciences 2006e) provided an indication of strandingrisk, and was used to interpret model results. Management options modeled in this study werealso considered for the Aquatic Protection, Mitigation, and Enhancement Opportunities report(Stillwater Sciences 2006f).1.3 Key QuestionsKey questions were identified by the ATS during the development of the Population Dynamics ofBull Trout and Spring Chinook Salmon study plan. The questions are answered throughout thisreport (Table 1-1).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board2

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable Error! No text of specified style in document.-1. Key questions and report sections inwhich they are addressed.Key question1. What factors affect the population dynamics of bull trout andspring Chinook salmon in the study area?2. How does the Project affect the population resilience (e.g.,ability to recover from a disturbance or population decline) ofbull trout and spring Chinook salmon through alterations in theamount or quality of habitat (e.g., physical habitat, foodavailability) at critical life-stages?3. To what extent can the abundance or resilience of the bull troutand spring Chinook salmon populations in the Study Area beincreased through habitat enhancement or changes inmanagement of the Project (e.g., passage at project dams,gravel augmentation, changes in flow in potential spawninghabitat)?4. Are there any special habitat features that must be protected toavoid population declines?Report section(s)Bull trout: Section 3.3Chinook salmon: Section 3.4Bull trout: Section 3.3.5Chinook salmon: Section 3.4.4Bull trout: Section 3.5Chinook salmon: Section 3.6Bull trout: Section 3.3Chinook salmon: Section 3.41.4 Study AreaThe Study Area (Figure 1-2) includes: (1) the mainstem McKenzie River downstream of TrailBridge Dam, and the Carmen-Smith Spawning Channel, (2) Trail Bridge Reservoir and theCarmen Bypass Reach upstream to Kink Creek, and including Sweetwater creek; and (3) theSmith Bypass Reach, Smith Reservoir, and tributaries above Smith Reservoir, upstream to naturalfish passage barriers. The limit to fish distribution in each reach was determined in the AquaticHabitats and Instream Flows study, during the process of estimating available habitat for use inthis study (Stillwater Sciences 2006b). Complete descriptions of the habitat in each of thesereaches are provided in the Aquatic Habitats and Instream Flows report (Stillwater Sciences2006b).For population dynamic modeling, the Study Area was modeled in subreaches, as follows.Bull trout population dynamics:• Trail Bridge Reservoir• Sweetwater Creek• Lower Carmen Bypass Reach (upstream of Trail Bridge Reservoir to Kink Creek)• Smith Bypass Reach• Smith Reservoir• Smith River and tributaries upstream of Smith ReservoirChinook salmon population dynamics:• Mainstem McKenzie River downstream of Trail Bridge Dam• Carmen-Smith Spawning Channel• Trail Bridge Reservoir• Lower Carmen Bypass Reach (upstream of Trail Bridge Reservoir to Kink Creek)• Smith Bypass Reach• Smith Reservoir• Smith River upstream of Smith Reservoir to confluence with Browder Creek28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board3

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report2 METHODSThe implementation of this study was conducted in collaboration with the ATS. Pursuant to thePopulation Dynamics of Bull Trout and Spring Chinook Salmon study plan (Stillwater Sciences2004a). Periodic Updates (communication to ATS members regarding study progress andfindings) and Decision Points (points at which a formal process is initiated to make decisionsabout changes to study implementation based on new information) were used to inform andcollaborate on decisions affecting the study. Documentation of issues addressed during thecourse of the study is available in the FERC record.The population dynamics models were developed in phases: (1) develop conceptual populationmodels to describe bull trout and spring Chinook salmon population dynamics in the Study Area,(2) gather data in relicensing and other applicable studies, (3) refine the population models basedon the gathered data, (4) use the population models to evaluate Project effects and potentialhabitat enhancement, fish passage facilities, and other management options on relative changes inbull trout and spring Chinook salmon population size, and (5) identify key habitat features, andProject features and operations, that influence population dynamics.The conceptual models provided a narrative and graphical description of the potential densitydependentand density-independent factors affecting each life-stage of bull trout and springChinook salmon. Population responses to changing habitat conditions were explored for specificlife-stages, first in conceptual models, and then in quantitative assessments using multi-stagestock-production population models.Multi-stage stock-production population models are mathematic representations of the startingnumbers of a life-stage (stock) and how the numbers change as the cohort goes through itsvarious life-stages (multi-stage); the ending numbers represent the population estimate of the lastlife-stage (production). Several life-stages were used to characterize the life-cycles of bull troutand spring Chinook salmon, and each life-stage was generally estimated by using two modelparameters. Parameters are descriptive variables that regulate population dynamics from one lifestageto the next, such as redd size, or density-independent survival of eggs-to-emergent-fry. Themodel parameter values were determined in collaboration with ATS, based on existing localinformation, field observations, and the scientific literature. Terms used in this report are definedin Appendix A.2.1 Collaboration and Peer ReviewIn collaboration with the ATS, initial conceptual models for bull trout and spring Chinook salmonwere developed in a workshop with agency and academic experts (Table 2-1) on 18–19 January2005. During a second collaborative workshop with the ATS on 4–5 October, participantsdiscussed the status of the quantitative population model parameters, values, and model structure(Table 2-1).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board4

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 2-1. Participants at 18–19 January and 4–5 October 2005 population dynamicsworkshops.Participant Affiliation QualificationsBaker, PeterBaxter, ColdenBell, EthanBelharz, MargaretBurchfield,StephanieDare, MatthewDowney, TimStillwaterSciencesIdaho StateUniversityStillwaterSciencesUSDA ForestServiceNMFSBoise StateUniversityEWEBMathematical modelerEcologist and expert onbull trout and food-webdynamicsAttendanceJanuary OctoberAquatic ecologist √ √Geomorphologist √ √Fisheries biologist withexpertise on ChinooksalmonEcologist and expert onbull trout ecology, andpopulation dynamics ofbull trout in reservoirsand tailracesFisheries biologist withlocal expertise on bulltrout and ChinooksalmonGray, Ann USFWS Fisheries biologist √Green, Keri Facilitator √Harris, David ODFWFisheries biologist withexpertise on Chinooksalmon and trout√√Homolka, KenODFWFisheries biologist withexpertise on Chinooksalmon and troutJundt, Melissa NMFS Hyraulic engineer √Stillwater Aquatic ecologist andKramer, Sharon√√Sciences fisheries biologistUSDA ForestKretzing, DaveGeologist √ √ServiceKruger, RickLigon, FrankODFWStillwaterSciencesFisheries biologist withexpertise on instreamflows and habitatStream ecologist withexpertise on populationdynamicsNewcomb, Steve EWEB Geologist √Parton, MikeStillwaterSciencesFisheries biologist√Patterson, Craig Resident Local expertise √Pedersen, DirkStillwaterSciencesFisheries biologist√√√√√√√√√√√√√28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board5

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParticipant Affiliation QualificationsRivera, RamonRaab, PhilSpalding, ShelleyUSDA ForestServiceUSDA ForestServiceUSFWSFisheries biologist withlocal expertise on bulltrout and ChinooksalmonRecreation expert, withlocal expertiseFisheries biologist withexpertise on bull troutecologyAttendanceJanuary OctoberTalabare, Andrew EWEB Fisheries biologist √ √van Donkelaar,CatrinEWEB Civil engineer √ √Wade, MarkZiller, JeffODFWODFWFisheries biologist withlocal expertise on bulltrout and ChinooksalmonFisheries biologist withlocal expertise on bulltrout and Chinooksalmon√√√√√√√√In addition to input from the ATS, peer review was conducted on drafts of this report. Reviewerswere selected for their expertise on bull trout and salmonid ecology, and for their experience withpopulation dynamics models. Drafts were reviewed by Dr. Matthew Dare 1 , R2 ResourceConsultants 2 , and Thomas Nickelson 3 . Peer review included evaluation of the populationdynamics models, and the presentation of the methods, analysis, and results described in thisreport. Peer review of this report will also be conducted by Dr. Paul McElhany 4 , and otheragency experts. Reviewers were asked to address the following questions:• Are the models structured appropriately for meeting study objectives? If not, why?• Are the parameters selected appropriate? If not, why?• Do you think that the model is useful for helping to inform management decisions? If not,why?• Are the conclusions of the report supported by the model stated too strongly, or notstrongly enough?The comments and suggestions of all reviewers were incorporated into subsequent drafts of thereport, and the models and report will continue to be updated based on new information, and theresponses of all reviewers (including the ATS).2.2 Conceptual ModelThe conceptual models provide a theoretical foundation for the quantitative models by identifyingfactors that limit life history stages, and factors that limit the overall production of thepopulations. The first step in developing the conceptual models was to summarize available1 Research Assistant Professor, Boise State University, bull trout ecology expert2 Private consultants, expertise on bull trout ecology, and population dynamics modeling3 Retired ODFW researcher, expertise in salmonid ecology and population dynamics modeling4 NMFS, expertise in salmonid ecology and population dynamics modeling28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board6

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportinformation on bull trout and spring Chinook salmon life histories by life-stage, focusing oninformation from the Study Area but including information from comparable areas outside of theStudy Area. In particular, information on life-stage-specific habitat use, growth, and densityindependentfactors (e.g., fecundity, sex ratio, gravel quality) and density-dependent factors (e.g.,redd superimposition, fry carrying capacity) that may limit the survival of each life-stage, wasalso obtained and reviewed. During the 18–19 January 2005 ATS workshop, participantsdeveloped conceptual models for bull trout and spring Chinook salmon based on a review of theavailable information, and local knowledge of the geomorphic, hydrologic, and biologicalcharacteristics of the Study Area. These conceptual models were developed with the ATS todescribe bull trout and spring Chinook salmon prior to European influences and under currentconditions, to evaluate the potential impacts throughout the system on these species.2.3 Quantitative Population ModelsTwo quantitative population models were developed for the Study Area in spreadsheet form usingMicrosoft Excel 2003®: one for bull trout and one for spring Chinook salmon. The models aremeant to provide a framework for investigating the relative influences of various factors on eachlife-stage. The intention of the models was to identify critical life-stages, and compare relativechanges in population size between alternative management scenarios. The utility of thesemodels, like all models, is a function of the quality of the data used to populate them, and in somecases models may be best used to identify additional information needs. This model however,serves as a useful and predictive tool because it is a compilation of all available data from recentfieldwork and the published literature, organized in a rigorous and transparent framework.The models follow the stock-production approach to population modeling, supported by a largebody of literature spanning several decades (e.g., Paulik 1973, Moussalli and Hilborn 1986,Sharma et al. 2005). Stock-production modeling is based on the idea of treating the number ofindividuals (P) in a cohort at a particular developmental stage, as a function of the number ofindividuals (S) in that cohort at an earlier developmental stage, in the function:P =f (S)Such a function f is called a stock-production relationship. This approach is useful because theimportant properties of f can often be deduced from general biological considerations. Inparticular, the function can often be expressed in terms of parameters r and K, where r representsthe effect of births and/or deaths independent of density considerations, and K is an upper limit onthe population size. A carrying capacity (K) is specified for all density-dependent stockproductionrelationships. Density-dependent relationships occur whenever food or spacelimitations regulate the number of individuals an area can support. Density-dependence appearsto be regulating population size when the densities of individuals’ decreases at the subsequentlife-stage beyond what is likely based on density-independent factors (r) alone (e.g. Grant andKramer 1990). Low population levels do not exclude the potential to fully saturate habitat at agiven life-stage , or to model small populations (e.g., Oosterhout et al. 2005), indeed populationmodels can be effective at indicating if certain habitat types are limiting the population andresulting in population declines (e.g., Nickelson and Lawson 1998). All terms used to describepopulation models are defined in Appendix A.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board7

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report2.3.1 Model developmentThe quantitative models were developed using the stock-production framework. Life-stages wereselected based on the conceptual model and the nature of available data. Once the life-stagestructure was determined, the basic model structure was assembled in an Excel spreadsheet. AVisual Basic interface was provided for data entry and parameter changes, and it allowedgraphical representation of individual stock-production relationships. The basic life-stagestructure, the factors selected as parameters, and default values for parameters and stockproductionforms were determined from local information, literature values, and the 18–19January 2005 collaborative population dynamics workshop.2.3.1.1 Model input parametersModel input parameters were selected by: (1) defining life-stages most appropriate for modeling,(2) acquiring data, (3) selecting appropriate stock-production models, and (4) selecting values forr and K.Life-stagesLife-stages for modeling were selected collaboratively during the January 2005 workshop (Table2-2). The models were run based intervals of time between a stock life-stage, and the resultingproduction into the next life-stage, defined here as a life-step (e.g., juvenile to subadult) (Table 2-3). The life-stages of the model correspond to the beginning of these intervals of development.Life history timing in the Study Area is described in the Fish Population Distribution andAbundance report (Stillwater Sciences 2006a). For bull trout, the model was run to estimateproduction of adults, and for spring Chinook salmon, the model was run to estimate production ofsmolts.Table 2-2. Life-stages modeled for bull trout and spring Chinook salmon.Life-stageSize (fork length [FL])MminBull troutEggs NA NAEmergent fry ~25 ~1Early fry 26–45 1–1.8Late fry 45–100 1.8–3.9Juvenile 100–250 3.9–9.8Subadult 250–400 9.8–15.8Adult > 400 > 15.8Female spawner > 400 > 15.8Spring Chinook salmonEggs NA NAEmergent fry ~35 ~1.4Fry 35–55 1.4–2.2Juvenile> 55 with no signsof smolting> 2.2Smolt> 55 with signs ofsmolting> 2.2Adult > 400 >15.8Female spawner > 400 >15.828 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board8

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 2-3. Life-steps modeled for bull trout and spring Chinook salmon.Life step Approximate dates Time intervalBull troutEmergent fry to early fry Mid-March to mid-April < 1 dayEarly fry to late fry Mid-March to mid-June 4 monthsLate fry to age 1+ juvenile Mid-June to April 9 monthsAge 1+ juvenile to age 2+ juvenile All year 1 yearAge 2+ juvenile to subadult All year 1 yearSubadult to adult All year 1 yearAdult to female spawner All year > 1 yearFemale spawner to deposited eggs Mid-September to mid-October1 monthDeposited eggs to emergent fry Mid-September to Mid-March6 monthsSpring Chinook salmonEmergent fry to fry March through April < 1 dayFry to juvenile March through September 6 monthsJuvenile to smolt All year 11 monthsSmolt to female spawner All year 3 yearsFemale spawner to deposited eggsMid-September to Mid-October1 monthDeposited eggs to emergent fry Mid-September to March 7 monthsInput dataThree basic types of data were needed to estimate life-stage-specific survival: (1) carryingcapacity of habitat for each life-stage, (2) density-independent mortality prior to attainingcarrying capacity, and (3) density-independent mortality occurring after attaining carryingcapacity. All existing local information was compiled (Appendices B and C), includinginformation obtained from local experts at the 18–19 January 2005 ATS workshop. Additionaldata were obtained during other relicensing studies (Appendix D and Appendix E), particularlythe Fish Population Distribution and Abundance study (Stillwater Sciences 2006a) and theAquatic Habitats and Instream Flows study (Stillwater Sciences 2006b). Where no site-specificdata were available, data from the scientific literature were used; when literature data wereapplied, studies conducted in regions with similar characteristics to the McKenzie River weregiven priority. Ultimately, decisions for input values were based on the best available science,and were discussed with the ATS and peer reviewers. All selected values and their sources aredocumented in Appendices D and E.Despite extensive data collection and literature review, when gathering biological input valuesthere is always a degree of uncertainty, and a potential for error. For example, many of the valuesfor the spring Chinook salmon model were based on monitoring the production and survival ofadult hatchery Chinook salmon released into Trail Bridge Reservoir. Naturally produced salmonmay behave, and perform, differently than the hatchery fish. In selecting input values, there wasan effort to be conservative for the resource to reduce the risk of concluding that a Project impactis negligible. In addition, a sensitivity analysis (Section 2.3.4) was performed, which examinedmodel outputs as a function of input variations. For example, if the habitat area data from theAquatic Habitats and Instream Flows study (Stillwater Sciences 2006b) underestimated availablehabitat by 25%, or even 50%, the sensitivity analysis would estimate any effects on thepopulation.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board9

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportIn this modeling approach, habitat area and fish density inputs are used to explicitly representcarrying capacity (K). In addition, mortality is explicitly represented by input values dependenton the rate of increase of the population (r). Factors such as food supply, growth rates, andhybridization are implicitly included based on available data used to adjust the mortality values.For example, if food availability was low in Sweetwater Creek, lower survival may result, andmortality would increase. Interactions between species are also implicitly incorporated byassuming that growth of bull trout (and thus survival) in Trail Bridge Reservoir is a function ofprey (including production of Chinook salmon), and conversely, that mortality for fry andjuvenile Chinook salmon is a function of the magnitude of predation by bull trout (and other troutspecies).AssumptionsTrail Bridge Dam currently blocks the upstream migration of spring Chinook salmon. Modelingconducted for this report assumes upstream passage at Trail Bridge Dam, although currently theonly Chinook salmon present are from annual ODFW releases of hatchery adult spring Chinooksalmon upstream of Trail Bridge Dam. The model also assumes that if there were fish passageadditional Chinook salmon adults migrate upstream, and there would be no decline in spawningat the Carmen-Smith Spawning Channel. Assumptions for all values used in the model aredescribed for each model scenario conducted in Appendices D and E.Stock-production modelsFour stock-production models were selected to “step” between selected life-stages in thepopulation dynamics models. The Beverton-Holt (1957) and “hockey stick” models (Barrowmanand Myers 2000) were typically used for density-dependent interactions (e.g., the life-step fromlate fry to juvenile when habitat limits the population). The linear model was used to reflectdensity-independent mortality (e.g., the step from eggs to emergent fry, in which mortality is notaffected by density). The redd superimposition model was also used for the step from femalespawners to deposited eggs. Each of these models is described below.The Beverton-Holt model allows production to increase toward a limiting carrying capacity (K)for the production (P) of the stock (S). The Beverton-Holt model was used both in its originalform, and in another form of the model (Beverton-Holt 2) when production approached carryingcapacity at a faster rate than assumed under the original form of the model. The equations for theBeverton-Holt models are:Beverton-Holt: P = r ⋅ K ⋅ S /( K + r ⋅ S)22Beverton-Holt 2: P r ⋅ K ⋅ S /( K + ( r ⋅ S))= ,where for all equations:P = production,r = density-independent effects,K = carrying capacity,S = stock valueThe “hockey stick” model was typically used as an alternative to Beverton-Holt 2; it allowsproduction to approach carrying capacity more rapidly than the Beverton-Holt 2 model. Thehockey stick model is a piecewise linear relationship with a slope defined by r prior to reachingcarrying capacity, reflective of complete density-independence (Barrowman and Myers 2000).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board10

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportOnce reaching K, however, the slope is zero, reflecting complete density-dependence. Thismodel was used to more clearly identify limiting factors. The equation for the hockey stickmodel is:P = min( r ⋅ S,K),where “min” takes the minimum of the values in parentheses.The linear model was used to represent relationships with no obviously relevant densitydependence(such as for deposited eggs to emergent fry), and to reflect density-independentmortality for fish during migration (since habitat is not limiting during migration). The equationfor the linear model is:P = r ⋅ SThe redd superimposition model (separate from the Escape 5.1 model described in Section 2.2.2)was only used in the bull trout population dynamics model. This model represents a “fit” of thenumber of deposited eggs to the number of female bull trout spawners. The step from female bulltrout spawners to viable eggs in the model has r and K values determined by the superimpositionrelationship. The equation for the superimposition model is:P = K ⋅−rS/ K( 1−e )For Chinook salmon, the hockey stick model was used instead of the superimposition model,because it provided a better fit to the Escape 5.1 results (discussed below) than thesuperimposition model did.Although the user can select any of the four models for any of the life-steps, model selectionshould consider density-dependence or density-independence. In this study, Beverton-Holt 2 andhockey stick models were used interchangeably for comparison. Although density-dependentrelationships are assumed to govern the transition from stock to production for many life-steps,the rate at which carrying capacity is reached was not modeled. The hockey stick model gives thesimplest and most abrupt change from density-independence to density-dependence, and so hasthe least complex interpretation of all the models. Given the lack of evidence to the contrary, anddue to its ease of interpretation, the hockey stick model was used for analysis. Use of theBeverton-Holt 2 model yields a similar result, but with a more gradual approach to carryingcapacity.r and K valuesThe “r” value is the effect of births and/or deaths independent of density considerations, resultingfrom factors such as fecundity, or dependence of egg survival on spawning gravel quality.Depending on the life-stage of interest and the stock-production model selected, the inputparameter r represents the fraction of adults spawning, fecundity, or a density-independentsurvival rate.The r values were typically based on estimates of survival from the literature and/or from theresults of other relicensing studies. For some of the life-steps, the r values were based on theliterature or professional judgment, since survival is difficult to estimate without individuallytagged animals, and life-stages younger than juveniles are typically difficult to tag. In addition,studies that attempt to estimate survival are often unable to separate survival into density-28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board11

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportdependent and density-independent components. If the abundance of a particular life-stage (say,juveniles) is well below the carrying capacity in a given system, then an estimate of survivalunder these conditions could be used to represent density-independent survival. For bull troutjuveniles, subadults, and adults, the estimates of r were based on estimated survival rates usingprogram MARK and PIT tag data (see the discussion of program MARK in the Fish PopulationDistribution and Abundance report, Stillwater Sciences 2006a).The “K” value represents the carrying capacity or population size limit for the life-stage ofinterest. The K values were typically based on density estimates using data from the FishPopulation Distribution and Abundance study (Stillwater Sciences 2006a) or the scientificliterature, and estimates of suitable habitat area from the Aquatic Habitats and Instream Flowsstudy (Stillwater Sciences 2006b). Habitat areas used in the model were based on mapping“guilds” (species and life-stages that have similar habitat requirements) of “good” habitat definedby criteria such as water depth, water velocity, distance to cover, and substrate size, as describedin detail in the Aquatic Habitats and Instream Flows report (Stillwater Sciences 2006b).Stock valuesThe population dynamics models require a stock “starting point” for the life-stage considered tobe the first step; the population of that life-stage must be known or estimated. For bull trout, thestock of subadults and adults was the starting point population estimate. Based on analysis ofmarked and recaptured PIT-tagged bull trout (see Section 3.3.1 below), 111 subadults and adultswere used as the initial bull trout population size as the starting point for model runs. Althoughthe bull trout estimates were based on only two years of data, the initial stock size that wasentered into the model only reflects the starting point, and does not typically affect the resultswhen the model is run to equilibrium. However, initial stock size may affect the running of themodel through a single production cycle, especially if the starting number of adults cannotproduce enough eggs to reach the carrying capacity for deposited eggs.For the spring Chinook salmon model, the initial population size of 141 adults was used as astarting point for model runs, based on the known number of adults released into Trail BridgeReservoir in 2004. For the spawning channel spring Chinook salmon model, the initialpopulation size of 135 adults was used as a starting point, based on the peak live count from 2004snorkel surveys (Stillwater Sciences 2006a).2.3.2 Escape 5.1 superimposition sub-modelLimited spawning gravels often result in redd superimposition, during which a later-arrivingfemale salmonid constructs a redd on top of an existing redd, causing mortality of eggs depositedearlier (Hayes 1987, McNeil 1964). The potential effects of spawning gravel availability on bulltrout and spring Chinook salmon egg production were modeled in separate sub-models toevaluate whether current spawning gravel availability may limit the species’ populations, andconversely, whether increasing spawning gravel availability could increase Chinook salmon orbull trout production. Results from the “Escape 5.1” sub-model were used to identify the r and Kparameters that were used in the superimposition stock-production step between spawners anddeposited eggs. The Escape 5.1 sub-model estimates egg mortality caused by reddsuperimposition. Using information on the temporal distribution of spawning, the observedspecies’ preference for particular reaches, available spawning gravel area, and redd constructionbehavior, the model estimates the number of viable eggs at the end of the spawning season.The model output reports "effective" egg production associated with a given escapement (numberof adults returning to spawn)—that is, the total number of eggs avoiding superimposition. Model28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board12

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportresults therefore reflect the number of viable eggs at the spawning period’s end, not the numberof emergent fry (because some eggs may die before emergence, for reasons unrelated tosuperimposition). By running the model for a range of escapements, the potential consequencesof superimposition can be displayed in a stock-production format. The model did not account forinter-specific superimposition between bull trout and spring Chinook salmon.2.3.2.1 Spatial structure of the Escape 5.1 sub-modelMeasurements of individual spawning gravel patches, based on the Instream Flow TechnicalCommittee (IFCT) habitat criteria (see Aquatic Habitats and Instream Flows report, StillwaterSciences 2006b), in the lower Carmen Bypass Reach were used in the Escape 5.1 sub-model toestimate K at the base flow (~160 cfs). K was estimated for different flows and different reachesby calculating the ratio of K based on Escape 5.1 to the K based on the total available gravel areaand the mean redd size. Reach-specific redd sizes were based on field measurements and wereincorporated into this calculation where possible (e.g., Sweetwater Creek).The Escape 5.1 model represents space in a discrete, rather than a continuous, fashion (i.e., eachgravel patch and redd is modeled as a unique unit). Redds and gravel patches are represented asrectangles composed of cells within a grid. Based on redd measurement in the lower CarmenBypass Reach, the size of a typical Chinook salmon redd is 5.4 m 2 (58 ft 2 ) and a typical bull troutredd is 1.8 m 2 (19 ft 2 ) (Stillwater Sciences 2006a). The model uses two distinct rectangles torepresent a redd—a defended region (which is four times the size of the redd) and an egg regioncomprising the redd proper (Figure 2-1). The typical redd described above represents the eggregion in which active digging, excavation, and egg deposition occurs. The defended regionrepresents the larger territory from which a female will actively exclude other spawners.2.3.2.2 Temporal structure of the Escape 5.1 sub-modelThe Escape 5.1 sub-model operates in discrete time steps, with each step representing one day.The sub-model is run for the length of a spawning season. The modeled movement of thespawners from their holding location to their spawning grounds over time was based on observeddates of redd initiation in the subreaches.The probability that a female will be assigned by the sub-model to any particular patch isproportional to the number of potential redd sites within the undefended area of the patch. Once afemale is assigned to a patch, the model randomly places a redd within the undefended area ofthat patch. As all the available patches in the reach become occupied, the total undefended areain the reach is too small to accommodate all females arriving within a time step, and theremaining females are carried over to the next time step (and treated as new arrivals). The redddefense time used in the model is defined by the period of time the female guards her redd, beforeshe dies (if she is a Chinook salmon) or migrates (if she is a bull trout) and the gravel areabecomes available for additional spawning. Redd defense time used in the model was based onobservations during spawning surveys in the Study Area of hatchery adult spring Chinook salmonreleased into Trail Bridge Reservoir (Stillwater Sciences 2006a). The redd defense time might bedifferent (greater or less), for naturally produced Chinook salmon spawning in the same habitat.Sensitivity analysis (Section 2.3.4) on the parameter for spawning habitat area addresses theuncertainties in redd defense time data.The status of each modeled redd or gravel patch cell—the number of eggs it contains, when theeggs were deposited, and whether or not the cell is currently being defended—is tracked andupdated daily. Modeled superimposition occurs when a new randomly placed redd is placed on28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board13

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reporttop of a cell that already contains a redd. When superimposition occurs within a cell, theconservative (worst case scenario) assumption is applied, in which the original eggs in thatparticular cell experience 100 percent mortality and are replaced by the new eggs. Thisconservative assumption may result in over-estimating the effects of superimposition, and thuspossibly identifying a spawning habitat limitation where none occurs. Sensitivity analysis(Section 2.3.4) on the parameter for spawning habitat area addresses this uncertainty. Thenumber of eggs remaining in all cells is then totaled at the end of the spawning period (36 daysfor bull trout and 27 days for Chinook salmon, based on field observations) to provide an estimateof viable eggs produced. Repetition of sub-model runs, in which the total numbers of femalespawners are varied, allows the construction of a model stock-production curve.2.3.3 Model executionTo run the bull trout or spring Chinook salmon population dynamics model, required input valuesare entered at the end of each row of the spreadsheet. The user enters appropriate values forparameters such as habitat area and density-independent survival, or accepts the given defaultvalues. The initial number of adults and subadults are entered directly into the spreadsheet(yellow cells). After entering all of the required input values, the model “steps through” thecalculations from “stock” to “production” for each life-step (Figure 2-2).2.3.4 Evaluation of factors affecting populationsThe models were used to determine the factors affecting populations of both species. OngoingProject effects were considered, as were potential changes to the Project or its operations, habitatenhancements, or management options to increase production of bull trout adults or springChinook salmon smolts. Key Project effects were assumed to be those that influenced theequilibrium adult bull trout population size, or annual production of Chinook salmon smolts.To determine the life-stages and parameters that most affect the equilibrium population, asensitivity analysis was conducted of the parameters and values in the model. The sensitivityanalysis was performed by building a spreadsheet macro that calculated the equilibriumpopulation size of subadults and adults with the initial parameter values (Appendix D and E), andthen by varying the parameter values as follows:• Decreasing initial value by 50%,• Decreasing initial value by 25%,• Increasing initial value by 33%, and• Increasing initial value by 100%.For each change in value, the model calculated the equilibrium population size, holding all othervalues constant. If altering the value for a parameter resulted in a change to the population size, itwas considered a sensitive parameter. However, sensitivity analysis does not explore thepotential interactions of multiple input values that are simultaneously increased or decreased. Forthe bull trout model, changes in values were so slight that any change in the equilibriumpopulation was considered sensitive. For the Chinook salmon model, only changes in valuesgreater than 10% were considered sensitive. For sensitive parameters, additional scrutiny wasfocused on the source of data, and the potential for the Project to influence those parameters.The population’s resilience to disturbance was evaluated by running the model to determine howmany years would be required for the population to recover to current levels following an acutedisturbance. Two catastrophic disturbance scenarios were evaluated: (1) a complete fish killsimultaneously in Carmen Bypass Reach, Sweetwater Creek, and Smith Bypass Reach (e.g.,28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board14

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportfloods), and (2) a complete fish kill in Trail Bridge Reservoir (e.g., toxic spill). These scenariosare unrealistically severe, but illustrate the resiliency of the population under an extremesituation. For each disturbance scenario, the model was run to equilibrium, mortality of theselected life-stage(s) was entered, and the number of years required to return to the equilibriumpopulation size was determined. No issues of genetic bottlenecks were addressed.2.3.5 Effects of changes in Project operations on populationsAlthough there are many potential scenarios that could be modeled, the scope of this analysis waslimited to the following potential habitat enhancement and management options:• Increased instream flows in the lower Carmen Bypass Reach and the Smith Bypass Reach(including a scenario with hypolimnetic releases from Smith Dam)• Large woody debris enhancements in the Carmen Bypass Reach, Smith Bypass Reach, andSweetwater Creek• Increased spawning gravel availability and/or quality in the Carmen Bypass Reach andSmith Bypass Reach• Habitat enhancements in Trail Bridge Reservoir, the Carmen-Smith Spawning Channel, orthe mainstem McKenzie River• Changes in the hatchery rainbow trout stocking program in Trail Bridge Reservoir• Changes in angling regulations at Trail Bridge Reservoir• Fish passage facilities at Trail Bridge Dam (including various entrainment mortalityscenarios)• Fish passage facilities at Smith DamIn each modeled scenario, management options were modeled implicitly by adjusting theappropriate values. For example, to evaluate an increase in instream flows, the values foravailable habitat were adjusted by flow for each life-stage [based on the Aquatic Habitats andInstream Flows study (Stillwater Sciences 2006b)]. The model runs discussed in this report donot address the combined effects on fish production assuming multiple changes in Projectoperations, or enhancements. For example, increases in instream flows are modeled, as areincreases in spawning gravel, but a scenario with both an increase in instream flows and a gravelaugmentation is not analyzed. Modeling of various scenarios will be conducted in support ofmeasures proposed for the License Application.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board15

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3 RESULTS3.1 Conceptual ModelsDuring the 18–19 January 2005 ATS workshop, participants developed conceptual models forbull trout and spring Chinook salmon based on a review of the available information, and localknowledge of the geomorphic, hydrologic, and biological characteristics of the Study Area.3.1.1 Bull trout3.1.1.1 Pre-European influenceThe conceptual model describes bull trout that prior to the closure of Trail Bridge Dam exhibiteda fluvial life history strategy (migrating from large rivers to spawn in tributaries) (Figure 3-1). Afluvial life history strategy is common for bull trout (Elle and Thurow 1994, Schill et al. 1994,both as cited in Flatter 2000), as is an adfluvial life history (migrating from lakes or reservoirs tospawn in tributaries) (Pratt 1985). Bull trout inhabit areas where they are often the dominantpiscivore (Rawson 1942, as cited in Donald and Alger 1993). Bull trout capitalized on large prey,including mountain whitefish (Prosopium williamsoni) and resident trout, which are consistentlyavailable (Boag 1987, Beauchamp and Van Tassell 2001). Bull trout are a long-lived fish (up to20+ years) with low adult mortality (Hagen and Baxter 1992). Low adult mortality could beachieved by such adaptations as nocturnal feeding (Goetz 1994, as cited in Muhfeld 2003,Swanberg 1997), muted spawning colors to lower predation risk, night spawning (Reiser 1997) orspawning near cover (James and Sexauer 1997), and secretive behavior (Muhlfeld et al. 2003).To achieve maximum long-term reproductive success, bull trout expend energy on growth andsurvival (to allow a long period of reproductive potential), and less on each reproductive event.This strategy is manifested by flexible spawning frequency (annual, e.g. Baxter 1995, or alternateyears, e.g. Fraley and Shepard 1989), small eggs (Budy et al. 2003), reduced redd defense (Boagand Hvenegaard 1997), low fecundity (Reiser et al. 1997, Budy et al. 2003), and delayedmaturation (Fraley and Shepard 1989, Budy et al. 2003).Bull trout are adapted to cold climate conditions (Beauchamp and Van Tassell 2001), asevidenced by their recolonization of western North America after Wisconsonian glaciation (Haasand McPhail 2001). Bull trout are able to grow large in cold conditions in part by maximizinggrowth at lower temperatures at rates faster than other salmonids (Baxter and McPhail 1996),undergoing extensive migrations for feeding (Fraley and Shepard 1989, Muhlfeld et al. 2003),selecting low velocity habitat associated with the stream bottom or cover (Baxter and McPhail1996), utilizing territorial behavior to ensure food availability (Gunckel et al. 2002), becomingpiscivorous at a relatively small size (Ben-James 2001, Beauchamp and Van Tassell 2001), andcannibalizing juveniles of their own species (Ben-James 2001, Beauchamp and Van Tassell2001). For salmonids, adult habitat is typically saturated if the species is long-lived and requireslow recruitment to maintain the population (Elliot and Hurley 1998, Morita and Yokota 2002).When food availability is adequate, space limitations for adult bull trout are manifested byagonistic behavior, resulting in high mortality or emigration of subadults. Based on professionaljudgment, productive adult bull trout habitat was available from the upper McKenzie Riverdownstream to, and including portions of, the Willamette River (Figure 3-2). Territorialism,piscivory, and cannibalism would result in very high mortality of fry and juveniles; however, this28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board16

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reporthigh mortality would have a low impact on the overall population because adult habitat (food andspace) would limit the size of the population (Morita and Yokota 2002).3.1.1.2 Current conditionsUnder current conditions, the bull trout population in the Study Area is affected by humanactivities, including effects related to the Project (Figure 3-3). In the McKenzie River basin,Cougar, Blue River, and Trail Bridge dams block access to spawning and rearing habitat, andreduce the transport of coarse sediment supply to spawning habitat downstream. Cougar Dam inthe South Fork McKenzie River is operated as a flood control project, and has disrupted flowpatterns in the mainstem McKenzie River, resulting in channel confinement and lost access tofloodplains (Ligon et al. 1995). Channel incision and the removal of large woody debris havereduced rearing habitat quality in the mainstem, including the loss of access to floodplains andoff-channel habitat. Trail Bridge Dam blocks volitional upstream passage and impactsdownstream passage. The occasional transport of adult and sub-adult bull trout from downstreamof Trail Bridge Dam into Trail Bridge Reservoir, and the introduction of fry (6,384 total) fromAnderson Creek into Sweetwater Creek from 1993 to 1999, has provided for some geneticexchange in the Upper McKenzie River basin. Aside from these occasional transfers of bull troutfrom downstream of Trail Bridge Dam into the reservoir, bull trout that migrate from thereservoir to the mainstem McKenzie River downstream of the dam are unable swim backupstream of the dam to spawn, and are essentially lost to the population upstream of Trail BridgeDam.Strategies allowing growth to large sizes in cold streams and extensive migrations have beenimpacted by changes in the prey base resulting from the construction of Trail Bridge Dam (e.g.,fewer whitefish, introductions of hatchery rainbow trout and spring Chinook salmon), and lack ofpassage at Trail Bridge Dam. Currently, bull trout use less of the mainstem McKenzie River dueto habitat alterations, passage barriers, and increased stream temperatures, compared withhistorical conditions (Figure 3-4). The creation of Trail Bridge Reservoir has increased suitableadult habitat (deep, slow water with high food availability) in the area upstream of Trail BridgeDam compared with the prior riverine reach. However, mortality factors in Trail BridgeReservoir affecting adult survival have increased from angling and entrainment into the TrailBridge turbine and spillway. Trail Bridge Reservoir has also provided habitat for hybridbrook/bull trout, and receives annual stocking of hatchery rainbow trout, both of which haveincreased competition for reservoir habitat.3.1.2 Spring Chinook salmon3.1.2.1 Pre-European influenceSpring Chinook salmon are an anadromous species, adapted to migrate upstream during thespring, when snow-melt flows allow access to habitat not available during the fall (when otherraces of Chinook salmon migrate) (Figure 3-5). Because spring Chinook salmon hold over thesummer prior to spawning in the fall, they require deep, cold pools. The conditions to supportadequate holding pools are typically found in large rivers at medium and high elevations,particularly in spring-fed systems such as the upper McKenzie River basin. However, in thehigh-gradient portions of these rivers, stream energy is often high and geological parent materialis not sufficiently weathered; thus the stream channel substrate is coarse and spawning gravelstend to be patchy and sometimes limiting (Stillwater Sciences 2006g).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board17

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSpring Chinook salmon often hold in pools adjacent to spawning habitat and spawn early in thefall, with fry emerging early in the spring. The fry may rear up to one full year in the McKenzie,Willamette, and Columbia rivers before migrating as large smolts to the ocean.Large runs of spring Chinook salmon used abundant spawning habitat in the upper reaches of theSouth Fork and mainstem McKenzie rivers. Based on the very high production that would beexpected from extensive spawning habitat, rearing juveniles would saturate the highly complexmainstem habitat, and in particular the extensive floodplain habitat in the lower mainstem duringwinter. Based on this conceptual model, juvenile habitat was limiting. Fry that could not locatesuitable habitat were forced to emigrate downstream to the Willamette River.3.1.2.2 Current conditionsUnder current conditions, Cougar, Blue River, and Trail Bridge dams block access to spawningand rearing habitat, and reduce the transport of course sediment supply to spawning habitatdownstream (Figure 3-6). Cougar Dam in the South Fork McKenzie River is operated as a floodcontrol project, and has disrupted flow patterns in the mainstem McKenzie River, resulting inchannel confinement and lost access to floodplains (Ligon et al. 1995). Channel incision hasreduced available spawning habitat and gravel quality. Channel incision and the removal of largewoody debris have reduced rearing habitat quality in the mainstem, including the loss of access tofloodplains and off-channel habitat.Since 1997, from 40 to 150 hatchery adult spring Chinook salmon have been released into TrailBridge Reservoir annually; spring Chinook salmon would otherwise not have access to habitatupstream of Trail Bridge Dam. Spring Chinook salmon spawn in available habitat in the CarmenBypass Reach and Smith Bypass Reach and fry emigrate to Trail Bridge Reservoir, where rearinghabitat is abundant. Rearing habitat in Trail Bridge Reservoir far exceeds the potentialproduction from available spawning habitat, indicating that spawning habitat is limitingproduction upstream of Trail Bridge Dam. However, daily reservoir fluctuations, predation bynative bull trout, and competition with and predation by annually stocked hatchery rainbow troutindicate the potential for high mortality of fry and juveniles rearing in Trail Bridge Reservoir.With channel incision and the removal of large woody debris in the mainstem McKenzie River(Ligon et al. 1995), juvenile rearing habitat in the mainstem McKenzie River has decreased inamount and complexity, resulting in a potential for reduced production and size of smolts.Smaller size at smolting contributes to reduced survival during migration into the Willamette andColumbia rivers and the marine environment, which have also been altered under currentconditions. Based on this conceptual model, in addition to spawning habitat limitations, fry andjuvenile survival (predation, entrainment, etc.) are also limiting adult escapement in the mainstemMcKenzie River, and upstream of Trail Bridge Dam.3.2 Population ModelsPopulation dynamics models were developed and used to quantitatively assess the relativeinfluence of Project operations (e.g., habitat conditions related to instream flows, and mortalityfactors related to entrainment) on bull trout and Chinook salmon populations. Model resultsshould not be interpreted as precise estimates of population size, but as predictions of relativechanges in estimated population size. Both Chinook salmon models (Trail Bridge Reservoirmodel and Carmen-Smith Spawning Channel model) predict smolt production by assuming asmolt-to-adult survival rate and running to equilibrium with returning adults. However, because28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board18

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportthe survival of smolt-to-adult survival was not measured in the Study Area, the primary means ofevaluating alternative management actions were based on relative differences in smoltproduction, rather than the long-term equilibrium population of adults. Model input values andtheir sources, for the bull trout and Chinook salmon models, respectively, under currentconditions and under conditions of varying management scenarios, are provided in Appendices Dand E.3.3 Factors Affecting Population Dynamics of Bull TroutThe conceptual model for bull trout hypothesizes that adult carrying capacity limits the currentpopulation, which is also supported by model results (described in detail below). Increasing thevalue of every other parameter in the model does not lead to an increase in the adult populationunless the carrying capacity of the subadult/adult population is increased. Following a cohortfrom Carmen Bypass Reach or Sweetwater Creek (Figure 3-7, from left to right) illustrates thatalthough many eggs are deposited, the carrying capacity for eggs is higher than the amount that iscurrently being deposited. Early fry in both reaches saturate the available habitat, and late fry andjuveniles have sufficient habitat so that carrying capacity is not currently reached. Mortalityduring each life-step (shown in Figure 3-7) results in population declines, such that nearly 500juveniles survive to reach the “Trail Bridge Reservoir” box. In the final life-step on the far rightof the diagram, subadults and adults saturate the habitat available for a total of 111 individuals.The juvenile life-stage would not begin to limit production unless the subadult/adult populationwas 800 or more. If adult mortality was decreased due to reductions in poaching or emigration,even fewer juvenile recruits would be required to sustain the current, or larger, population. Ifsubadult/adult habitat were not limiting, a population of greater than 800 would be expected to bepresent. If the equilibrium or current population is less than 800, then this lesser populationwould support the conclusion that subadult/adult habitat is limiting. Data discussed belowindicate that the population in Trail Bridge Reservoir in 2004 was estimated at 111 (29–307)subadults and adults combined.3.3.1 Subadult/adult population estimatesThe subadult/adult bull trout populations in Trail Bridge Reservoir was estimated using threemethods (Stillwater Sciences 2006a): (1) enumerating redds to back-calculate the number ofspawning adults, (2) using a modified Petersen estimator on recaptured fish, and (3) running acomputer program called “Program MARK” (White 2005). Program MARK was used toestimate subadult, adult, and juvenile bull trout abundance for two years (2004 and 2005) usingthe history of PIT tag detections for individual fish tagged and re-sighted during angling andreservoir trapping efforts. Although the estimates using the three approaches were similar (Table3-1), the population estimate from the Program MARK analysis was used for the modeling effort,because it was estimated for two years, and included subadult/adult life-stages. The combinedestimate of 111 subadults and adults is within the range of the other estimates, with the exceptionof the Baited Video Station estimate (Table 3-1). The value of 111 was selected as intermediatebetween the low estimate of 70 spawning adults based on redd counts alone, and a high estimateof 254 based on the Baited Video Station. The selection of 111 for the subadult/adult carryingcapacity did not influence model results. The model was not “fitted” to this estimate, and whenthe carrying capacity for subadults and adults is varied within a reasonable range (as describedbelow), the model interpretation is the same (namely, that subadult/adult habitat is limiting thepopulation). If the subadult/adult bull trout population in Trail Bridge Reservoir is actually largerthan 111, which seems possible, the interpretation of the results would not change unless thepopulation was greater than 800.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board19

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 3-1. Population estimates for subadult/adult bull trout. Confidence intervals inparentheses when available. Based on Stillwater Sciences (2006a).Life-stage Year MethodAdults20042004Two adults for everyconfirmed bull trout redd,assumes annual spawningPetersen estimator appliedto redd counts and PIT tagrecaptures of adultsEstimated population size± 95% C.I.70 a141 ± 412005 Program MARK 105 (30–280)Adults/subadults 2004 Program MARK 111 (29–307)combined2004Baited Video Stationestimate for bull trout > 254 (128–538)200 mm (7.9 in) FL ba This estimate is conservative, because a proportion of the population spawns bi-annually, and someproportion of the unknown redds were likely bull trout.b This estimate is higher that the other estimates partly because it includes large juveniles in the calculation.Subadult/adult habitat was mapped in the Study Area (Stillwater Sciences 2006b) based on watervelocity and water depth habitat criteria developed by the IFCT. No subadult or adult habitat wasmapped in Carmen Bypass Reach at any flow, or in Sweetwater Creek. PIT-tagged subadult oradult bull trout were rarely detected migrating into the Carmen Bypass Reach outside of thespawning season, and no subadult or adults were observed during snorkel surveys (StillwaterSciences 2006a), which corroborates the habitat mapping results. Subadult/adult habitat wasmapped in Trail Bridge Reservoir, mostly along the margins of the reservoir to 15-m (50-ft) deep.The conceptual model for bull trout hypothesizes that adult carrying capacity limits the currentpopulation, which is also supported by model results. Increasing the values of all otherparameters in the model does not lead to an increase in the adult population until the carryingcapacity of the adult population is increased. Subadult/adult bull trout habitat was modeled inTrail Bridge Reservoir using a combined carrying capacity, because both life-stages arepiscivorous and use the same habitat. If 111 subadults and adults are assumed to be in thereservoir (of which 85 are modeled to be mature adults based on estimated adult trout mortalityrates), then to maintain the population, only 26 recruits from the juvenile life-stage are neededeach year (Figure 3-7), far fewer than estimated under current conditions (Section 3.3.3).Densities of subadult/adult bull trout in Trail Bridge Reservoir are high relative to most systems(Table 3-2), with the exception of Lake Billy Chinook in the Deschutes River basin. Lake BillyChinook appears to have the highest reported density of subadult/adult bull trout in systemswhere bull trout co-occur with other species (Table 3-2), with over 13,000 subadult/adult bulltrout estimated in 2004 (D. Ratliff, pers. comm., 2005). In reservoirs with large populations ofbull trout, prey sources are often abundant, such as kokanee salmon (Oncorhynchus nerka) inLake Billy Chinook, and pygmy whitefish (Prosopium coulteri) in Lake Chester Morse.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board20

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 3-2. Bull trout subadult/adult (sexually mature and/or greater than 250 mm) populationestimates reported in the literature, and the estimated population in Trail Bridge Reservoirassuming the same densities were achieved.LocationSizeArea (m 2 Shoreline)(m)TrailBridge 255,164 4,792Reservoir 1Subadult/adultpopulationestimate(95% CI)111(29–307)fish/m 2Densityfish/mshorelineEstimatedpopulation in TrailBridge Reservoirassuming samedensities as otherwaterbodies basedon:fish/m 2 fish/mshoreline0.000435 0.0232 111 111CitationStillwaterSciences(2006a)ArrowrockReservoir12,750,000 NA471(389–590)0.0000369 NA 9 NA Flatter (1999)Pinto Lake 1,245,000 NA 410 0.000329 NA 84 NA Herman (1997)LowerKananaskis 6,460,000 NA < 100 0.0000155 NA 4 NA Stelfox (1997)LakeLake BillyD. Ratliff, pers.15,800,000 100,300 13,331 0.00084 0.133 214 637Chinookcomm., 2005CougarM. Wade, pers.5,618,941 28,477 100 0.000018 0.00351 5 17Reservoircomm., 2005LakeUSFWSChester 6,798,718 18,700 1,500 0.00022 0.080 56 384(2004b)MorseNA= not available1 Based on average pool elevationIf the maximum density of subadult/adult bull trout in Lake Billy Chinook were to be achieved inTrail Bridge Reservoir, then the potential carrying capacity would be approximately 640subadult/adult bull trout (Table 3-2). At this carrying capacity, an estimated 150 juvenile-tosubadultrecruits would be needed each year, which are fewer than the current juveniles in thelower Carmen Bypass Reach (Section 3.3.3). This is not to say that the Study Area couldnecessarily support a population of 640 subadults and adults, but even if that population wasachieved, adult habitat would still be limiting.3.3.2 Sensitivity analysisA sensitivity analysis was conducted on the bull trout model under current conditions (Table F-1).This sensitivity analysis indicated that the current bull trout population in Trail Bridge Reservoiris most strongly influenced by the model parameters for subadult/adult habitat, and by the densityof subadults and adults (Table 3-3). No other model parameters influenced model results, unlessa carrying capacity for subadults and adults of nearly 500 was assumed, at which point the modelwas slightly sensitive (< 1% change in adult population) to earlier life-stages (Table 3-4, Table F-2). The model scenarios with a K of 500 assume that spawning habitat availability, and all otherparameters, remains unchanged (Table F-2). Spawning habitat is not predicted to be limitinguntil a population reaches 150 female bull trout, which is not predicted unless K for28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board21

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportsubadult/adult bull trout was to reach over 700, since only a portion are females that spawn in agiven year, in either Carmen Bypass Reach or Sweetwater Creek.Table 3-3. Summary of sensitivity analysis on bull trout population under current conditions(subadult/adult K=111). The model was not sensitive to any other parameters.Subadult/adult population estimate based on varying inputModel parametervalue50% 25% Current 33% 100%decrease decrease value increase increaseSubadult/adult available habitat inTrail Bridge Reservoir56 83 111 148 223Subadult/adult density 56 83 111 148 223Table 3-4. Summary of sensitivity analysis on bull trout population assuming an increase insubadult/adult carrying capacity (K=500). The model was not sensitive to any other parameters.Subadult/adult population estimate based on varying inputModel Parametervalue50% 25% Current 33% 100%decrease decrease value increase increaseEarly fry rearing habitat in CarmenBypass Reach498 500 500 500 500Early fry rearing density 498 500 500 500 500Age 1+ to age 2+ juvenile survival inCarmen Bypass Reach498 500 500 500 500Age 1+ to age 2+ juvenile survivalduring migration from Carmen Bypass 498 500 500 500 500ReachEarly fry to late fry survival in CarmenBypass Reach498 500 500 500 500Late fry to juvenile survival in CarmenBypass Reach498 500 500 500 500Subadult/adult available habitat inTrail Bridge Reservoir382 382 500 570 570Subadult/adult density in Trail BridgeReservoir382 382 500 570 570Age 1+ to age 2+ juvenile survival inTrail Bridge Reservoir476 500 500 500 500Age 4+ to > 5+ adult survival in TrailBridge Reservoir417 494 500 500 5003.3.3 Juvenile-to-subadult recruitmentUnder current conditions, juveniles would have to be reduced to a population of 26 beforejuvenile-to-subadult recruitment is limiting to the population. The model currently estimates thataround 450 age 2+ juveniles are produced from the lower Carmen Bypass Reach and SweetwaterCreek each year (including annual mortality while rearing, during migration, and during reservoirresidency). Though juvenile bull trout numbers likely fluctuate annually, population estimates ofjuvenile bull trout in the Study Area (Table 3-5) are slightly lower than model predictions, but arewithin the 95% confidence intervals.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board22

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 3-5. Population estimates for juvenile bull trout. Confidence intervals in parentheseswhen available.Year20042005MethodTotal number observed in snorkel survey of allhabitat units. Not corrected for diver observationprobability.Extrapolated snorkel survey results. Minimum isthe number observed during surveys. Notcorrected for diver observation probability.Modified Petersen estimator. Minimum is thenumber of PIT-tagged juvenile bull trout.Program MARK. Minimum is the number ofPIT-tagged juvenile bull trout.Estimated population size ±95% C.I.14 in Sweetwater Creek377 (168 minimum) in lowerCarmen Bypass Reach351 (121–604) in Trail BridgeReservoir264 (121–725) in Trail BridgeReservoirThe empirical and the modeled data indicate that subadult/adult habitat is the limiting parameter.If the subadult/adult population in Trail Bridge Reservoir were estimated at 307 (the upper limitof the 95% confidence interval from the MARK analysis) (Table 3-1), then only 72 juvenile-tosubadultrecruits would be needed annually to maintain the population. Even if the total numberof captured and PIT-tagged juvenile bull trout (121) were the true juvenile population size (Table3-5), sufficient numbers of juvenile bull trout would be available to recruit to the subadult lifestageeach year. Estimates of current recruitment of juvenile to subadults are higher than theavailable habitat for subadults and adults. Therefore, both the model and empirical data indicatethat the limiting parameter is adult habitat.Although many fewer juveniles are required to maintain the population, the “excess” juveniles areimportant in ecological interactions not explicitly addressed by the model. Juveniles that are notrecruited into the subadult population in Trail Bridge Reservoir are assumed either to migratedownstream seeking available habitat, or to perish (e.g., from predation) (Figure 3-7). Thisassumption is corroborated by detections of PIT-tagged juvenile bull trout emigrating from TrailBridge Reservoir (Stillwater Sciences 2006a). However, the bull trout model does not addresspopulation dynamics downstream of Trail Bridge Dam. The juvenile population migratingdownstream is assumed to suffer some level of mortality at Trail Bridge Dam, and juveniles thatsurvive rear in the mainstem McKenzie River. Their potential contribution to the downstreampopulation is dependent on the current carrying capacity for juveniles and subadults/adults in themainstem, and the number of bull trout currently produced from Anderson and Ollalie creeks,which were not modeled in this study.Production of juveniles is valuable to the overall population for several additional reasons, eventhough carrying capacity of subadult/adult bull trout ultimately limits the abundance of thepopulation. First, larger juvenile bull trout (age 1+ and 2+) provide a greater contribution to adultescapement than 0+ migrants in adfluvial populations; therefore, providing and maintaining highquality rearing habitat is important for maintaining recruitment (Downs et al. in press). Second,the bull trout juvenile life-stage lasts for at least two years, so multiple cohorts are represented. Ifa major disturbance occurs, the juveniles in the population would likely buffer the populationagainst substantial population loss (see Section 3.3.5); therefore “excess” juveniles that areproduced in the Study Area may increase the stability and resilience of the population. Third,juvenile bull trout that leave Trail Bridge Reservoir and rear in the McKenzie River downstreamof Trail Bridge Dam may increase the bull trout population downstream of Trail Bridge Dam and28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board23

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportincrease population stability and resilience to disturbance in that population over time. Finally,juvenile bull trout may be an important part of the diet of adult and subadult bull trout in someyears (Beauchamp and Van Tassell 2001).3.3.4 Early life-stages3.3.4.1 Spawning/eggsModel results indicate that sufficient spawning habitat is available to incubate more bull trouteggs than are laid in both the Carmen Bypass Reach and Sweetwater Creek. Spawning surveys(Stillwater Sciences 2006a) indicated that although spawning occurred on most available gravelpatches, many patches had additional gravel area that was unused by spawning adults, suggestingthat more spawning habitat was available than was used (or that it was unsuitable in some waythat was not measured).The Escape 5.1 sub-model was used to estimate the number of deposited eggs at varying levels ofspawning escapement, considering redd superimposition for the spawner-to-deposited-eggs step.Results from the Escape 5.1 sub-model were used to quantify r and K parameters in thesuperimposition stock-production relationship between spawners and deposited eggs. In CarmenBypass Reach a mean redd area of 1.82 m 2 (19.6 ft 2 ), and in Sweetwater Creek 0.5 m 2 (5.4ft 2 ) wasused, based on total station surveys of the dimensions of all constructed bull trout redds observedin the each reach in 2004 (Stillwater Sciences 2006a). A defended area (four times the redd area)was also used in the calculation. Values for each parameter, as well as their sources, are providedin Table D-2. At the current population level, low levels of superimposition were predicted forCarmen Bypass Reach, which was corroborated during 2004 spawning surveys (StillwaterSciences 2006a). In Sweetwater Creek superimposition is not predicted to limit spawning habtiatavailability until a population of over 300 females is reached, even using the larger redd areavalues observed in Carmen Bypass Reach. The ratio of K as determined by the superimpositionmodel fitted to Escape 5.1 results, to the K based on gravel area and mean redd size, was high(0.84) in both reaches, which indicates a relatively small change in carrying capacity due tosuperimposition. Based on these modeling results, spawning habitat is not currently limiting thebull trout population in the Study Area.Although the current level of bull trout spawning is not high enough to result in significantsuperimposition, if Chinook salmon escapement increased, the numbers of bull trout and Chinooksalmon spawners combined could approach levels causing significant superimposition (~150females, Figure 3-8) based on current spawning gravel availability in the Carmen Bypass Reach.However, because bull trout typically spawn later in the season than Chinook salmon (StillwaterSciences 2006a), bull trout redds are unlikely to be at risk from Chinook salmon superimposition.3.3.4.2 FryIncubation survival for bull trout eggs is expected to be moderate in the Carmen Bypass Reach,and relatively low in Sweetwater Creek, based on field measurements of gravel permeability(Stillwater Sciences 2006d). Survival estimates used in the model were based on a relationshipbetween permeability (ability to deliver oxygen and remove metabolic waste products from eggs)and egg-to-emergence survival (Tagart 1976, McCuddin 1977) developed for Chinook and cohosalmon (no direct measurements of egg-to-emergence survival were conducted). Lower gravelpermeability in Sweetwater Creek and the Carmen Bypass Reach are likely associated with anattenuated peak flow response in spring-dominated systems; the majority of high flow events in28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board24

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportthe Carmen Bypass Reach and Sweetwater Creek likely result in partial bedload mobility wherefiner grains on the surface are transported but the channel bed is not scoured to depth.Additionally, the channel bed is strongly armored with coarse cobbles and boulders due to glacialinfluences and limited sediment supply associated with the High Cascades terrain, which furtherlimits channel bed scouring. A suppressed frequency of scour and fill events may lead to higherfine sediment content in the subsurface material and decreased permeability.Increasing egg-to-emergent fry survival (e.g., improved gravel quality) would increase thenumber of emergent fry, but since both early fry and subadult/adult life-stages are limiting,increasing emergent fry would not affect the adult population size. Mechanisms for improvinggravel quality could include gravel augmentation, and/or limiting the delivery of fine sedimentfrom roads.The abundance of each cohort of bull trout is first constrained by the available habitat for earlyfry (Figure 3-7). Early fry rearing habitat was rare in the Study Area (Stillwater Sciences 2006b)based on a set of restrictive criteria (e.g., very slow, shallow water, with abundant cover frominterstitial space or detritus) developed by the IFCT. In the model, all early fry that do not findsuitable habitat migrate to Trail Bridge Reservoir, with high mortality from predation during theirmigration. Although it is possible that the criteria used to estimate available early fry habitatwere too restrictive, rotary screw traps in the Carmen Bypass Reach captured more early bulltrout fry than any other life-stage, supporting model results that predict an early fry migration dueto limited early fry habitat. In addition, direct bank-side observation and snorkel surveys confirmrelatively low abundance in both reaches (although fry are difficult to observe).An increase in early-fry habitat of over 120% would be required before the next life-stage (latefry)would be limiting. The instream flows analysis (Stillwater Sciences 2006b) indicated a peakin early fry habitat at 205 cfs in the Carmen Bypass Reach, which is the current base flow thatoccurs during spring when fry emerge. Therefore, early fry habitat would not increase byincreasing instream flows over 205 cfs. Large woody debris enhancements in the Carmen BypassReach have likely increased available early fry habitat, as discussed in Section 3.5.2 below, buthabitat for juveniles is modeled to have increased as well, so early-fry habitat is still consideredlimiting.Habitat for late fry is abundant and not limiting, in both the Carmen Bypass Reach andSweetwater Creek, and losses during this life-stage are related to moderate mortality rates fromsources such as predation and disease, rather than competition for space. Very few late fry werecaptured at rotary screw traps in Carmen Bypass Reach, providing additional evidence thathabitat for late fry is not currently at carrying capacity in the Carmen Bypass Reach. Rotaryscrew trap captures in Sweetwater Creek in 2005 were also consistent with model predictions of asmall pulse of early fry, no late fry, and the bulk of migration occurring as age 1+ or 2+ juveniles.3.3.5 Resiliency to disturbanceThe bull trout population upstream of Trail Bridge Dam exhibited a high resiliency in recoveringfrom a modeled catastrophic fish kill of all life-stages of bull trout in the Carmen Bypass Reachand Sweetwater Creek (Table 3-6). In the years following the fish kill, the adult population inTrail Bridge Reservoir would be maintained by the abundance of age 2+ juveniles and subadultsrearing there. However, once the current population of age 2+ juveniles became subadults, thelack of recruitment of age 2+ juveniles from Carmen Bypass Reach and Sweetwater Creek wouldlimit recruitment to the subadult life-stage; for the next two years, the adult population woulddecrease based on the estimated annual adult mortality of 20%. Three years following the28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board25

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportdisturbance, age 2+ recruits from Carmen Bypass Reach and Sweetwater Creek would againbecome available to recruit to the subadult life-stage in Trail Bridge Reservoir, and 4 yearsfollowing the disturbance, the subadults would be available to recruit to the adult population. Theage structure of the adult population would be biased towards older (> age 5) individuals untilsubadult to adult recruitment resumed.Table 3-6. Resiliency of adult bull trout population to disturbance.Disturbance scenarioAdult population in years following fish kill 10 1 2 3 4Fish kill in Carmen Bypass Reach andSweetwater Creek85 85 68 54 85Fish kill in Trail Bridge Reservoir 0 0 0 85 851 Current population estimated at 85 adults.The bull trout population upstream of Trail Bridge Dam also showed a high resiliency inrecovering from a modeled catastrophic fish kill of all life-stages of bull trout in Trail BridgeReservoir (Table 3-6). During the year of the fish kill, the subadult/adult population would beextirpated. By the first year following the disturbance, age 2+ juveniles would seed the reservoirfrom production in the Carmen Bypass Reach and Sweetwater Creek, and by the second yearthese juveniles would recruit to the subadult life-stage, and to the adult life-stage within threeyears following the disturbance. The age structure of the adult population would be biasedtowards younger (all age 4) individuals in the third year following the disturbance, and theproportion of older adults would increase each year thereafter.Overall, short-term alterations in the amount or quality of habitat (e.g., physical habitat, foodavailability) at critical life-stages are not likely to cause long-term effects on the bull troutpopulation. The bull trout population is highly resilient to disturbance based on:• Age structure of adult population from age 4+ to age 7+ (Stillwater Sciences 2006a),• High production of juveniles relative to the adult population,• Spawning habitat in both the Carmen Bypass Reach and Sweetwater Creek, and• Habitat supporting rearing to age 2+ juveniles in both the Carmen Bypass Reach andSweetwater Creek.The high production of juveniles relative to the adult population is maintained in the Study Areain large part by extensive rearing opportunities for juveniles in Carmen Bypass Reach, whererearing to age 2+ is common (Stillwater Sciences 2006a). Therefore, long-term reductions in therearing habitat amount or quality in the Carmen Bypass Reach could reduce the resiliency of thepopulation.The evaluation of resiliency does not consider the long-term effects of disturbances or populationisolation on population genetic variability. The effects of the Project on bull trout genetics isdiscussed in the Aquatic Habitat Connectivity report (Stillwater Sciences 2005j).3.4 Factors Affecting Population Dynamics of Spring Chinook SalmonPopulation modeling of spring Chinook salmon was conducted assuming that Chinook salmonadults gain access to habitat upstream of Trail Bridge Dam (volitional or by other means). SpringChinook salmon in the Study Area rear only briefly in the Carmen Bypass Reach and Smith28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board26

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportBypass Reach before migrating downstream to Trail Bridge Reservoir (Stillwater Sciences2006a). The reservoir provides abundant rearing habitat, and the modeling results indicate thatthe population is not sensitive to available habitat in the bypass reaches, with the exception ofspawning habitat. As a result, the spring Chinook salmon population in the Study Area is moststrongly affected by available spawning habitat, and survival of fry, juveniles, and smolts in TrailBridge Reservoir. Density-independent and density-dependent factors have varying influences onhow the population is regulated (Figure 3-9). For example, following a cohort from CarmenBypass Reach from left to right, one sees that the deposition of eggs is at carrying capacity, andthat all fry produced are able to reach sufficient habitat, such that fry carrying capacity is notcurrently reached. High mortality during each life-step (shown in Figure 3-9) results inreductions between subsequent life-stages, resulting in over 1,200 smolts produced from TrailBridge Reservoir.Although smolts are the primary life-stage for evaluating the spring Chinook salmon population,fry also have considerable ecological value. Chinook salmon fry are an important part of the foodbase for juvenile and older bull trout, as well as for cutthroat trout (Oncorhynchus clarki clarki)and stocked rainbow trout in Trail Bridge Reservoir and in the McKenzie River downstream ofTrail Bridge Dam. Chinook salmon fry that leave Trail Bridge Reservoir and the Carmen-SmithSpawning Channel may also rear in the mainstem McKenzie River and emigrate as either age 0+or 1+ smolts. In summary, fry leaving the Study Area are not “losses,” and potentially survive tobecome sexually mature adults.3.4.1 Sensitivity analysisThe sensitivity analysis conducted on the Chinook salmon model under current conditionsindicated that the Chinook salmon population is primarily influenced by the model parameter“Marine smolt-to-adult survival” (last row of Table 3-7, Table G-1). While this parameterstrongly affects model results, this study does not address downstream or marine smolt survival;the smolt survival parameter was only included to allow the population model to estimateescapement and predict equilibrium conditions. However, the influence of this parameterindicates the importance of smolt-to-returning-adult survival in the Chinook salmon life-cycle.The model is also sensitive (indicated by a greater than 10% change in adult escapement withvarying input value) to available spawning habitat in the Smith Bypass Reach, and is verysensitive to survival of early life-stages. The sensitivity of the model to these parametersindicates that spawning habitat availability and early life-stage survival are key elements in thepopulation dynamics of spring Chinook salmon. The potential uncertainty in the input values forthese parameters was addressed by running the model assuming the input value was either lower,or higher than the value selected (Table 3-7). What is apparent is that if the selected value forspawning habitat area in the Smith Bypass Reach, for example, was underestimated by 33% (e.g.,if superimposition effects were over-estimated), smolt production (and thus adult returns) wouldbe only slightly higher than predicted. Clearly the interpretation of the results, namely thatspawning habitat is limiting production in the Smith Bypass Reach, is not changed.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board27

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 3-7. Summary of Chinook salmon model sensitivity analysis under current conditions.Only parameters having a > 10% change in adult escapement with an increase or decrease ofthe input value are shown.Adult population estimate based on varying input valueModel parameter 50%decrease25%decreaseCurrentvalue33%increase100%increaseProportion of female spawners 42 85 100 100 100Pre-spawn adult female survival 42 85 100 100 100Proportion of spawners in CarmenBypass versus Smith Bypass Reach72 89 100 35 35 aCarmen Bypass Reach spawning habitat 76 88 100 116 116Carmen Bypass Reach redd area 116 116 100 88 76Carmen Bypass Reach fecundity 72 88 100 116 147Carmen Bypass Reach eggs-to-emergentfry survival72 88 100 116 148Carmen Bypass Reach emergent-fry-tofrysurvival72 88 100 112 112 aCarmen Bypass Reach migrantemergentfry-to-emergent-fry reservoir 79 91 100 113 138survivalCarmen Bypass Reach migrant fry-to-fryin reservoir survival93 97 100 105 114Smith Bypass Reach spawning habitat 81 92 100 111 127Smith Bypass Reach redd size 127 111 100 92 81Smith Bypass Reach fecundity 81 92 100 111 130Smith Bypass Reach eggs-to-emergentfrysurvival81 92 100 110 127Smith Bypass Reach migrant-fry-to-fryin reservoir survival82 92 100 110 131Smith Bypass Reach fry habitat 95 98 100 103 110Smith Bypass Reach fry density 95 98 100 103 110Smith Bypass Reach fry-to-juvenilesurvival81 92 100 108 108 aTrail Bridge Reservoir emergent-fry-tofrysurvival79 91 100 113 138Trail Bridge Reservoir fry-to-juvenilesurvival38 74 100 128 183Trail Bridge Reservoir juvenile overwintersurvival38 74 100 128 128 aTrail Bridge Reservoir juvenile-to-smoltsurvival21 64 100 111 111 aDownstream passage smolt survival atTrail Bridge Dam21 64 100 125 125 aMarine smolt-to-adult survival 21 64 100 133 200aThe 100% increase in value results in a survival input of greater than 100%, so no increase in population is estimated.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board28

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3.4.2 Early life-stages3.4.2.1 SpawningIn the Carmen Bypass Reach and Smith Bypass Reach, spawning habitat under current conditionslimits the production of emergent Chinook fry. In the Carmen Bypass Reach, use of spawninghabitat is close to the carrying capacity of available spawning habitat, and modeled increases inspawning habitat do not result in large increases in smolt production, unless escapementsimultaneously increases (e.g., smolt-to-adult survival increases). In contrast, very little suitablespawning habitat was mapped in the Smith Bypass Reach under current conditions, and spawninghabitat there appears to limit production of smolts from the Study Area. Few (< 5) redds aretypically observed in the Smith Bypass Reach each year. The exception was the 2004 spawningseason, during which 12 redds were observed. The beginning of the 2004 spawning season in theSmith Bypass Reach coincided with a spill event from Smith Dam, ranging from 18 to 80 cfs on22–23 September, which, based on the Aquatic Habitats and Instream Flows study (StillwaterSciences 2006b) likely increased available spawning habitat, or attraction to the Smith BypassReach. Redd size in the Smith Bypass Reach (0.9 m 2 [9.7 ft 2 ]) is relatively small compared withthat measured in Carmen Bypass Reach (5.4 m 2 [58.1 ft 2 ]), and compared with Chinook salmonredds in other locations (Burner 1951). For modeling management actions, redd sizes in SmithBypass Reach were assumed to increase with increasing spawning habitat.At the current population level, a low level of superimposition was predicted by the Escape 5.1sub-model for Carmen Bypass Reach, and was observed during 2004 spawning surveys(Stillwater Sciences 2006a). The ratio of K as determined by the Escape 5.1 sub-model results, tothe K based on observed gravel area and mean redd size, was low (0.30). This ratio reflects therelatively short amount of time Chinook salmon are spawning in the reach in comparison with theredd defense time, rather than any effect of superimposition. Once created, most redds weredefended until nearly the end of the run. Therefore, an individual patch of spawning habitat mayhave been much larger than the mean redd size, yet its use was dictated by the redd defense area(4 times the size of the redd).Although the current levels of Chinook salmon and bull trout spawning are not high enough toresult in significant inter-specific superimposition, if Chinook salmon escapement increased, thenumbers of bull trout and Chinook salmon spawners could approach levels that would result insignificant redd superimposition in the Carmen Bypass Reach (~30 Chinook salmon females,Figure 3-10). Because bull trout typically spawn later in the season than Chinook salmon(Stillwater Sciences 2006a), redd superimposition potentially could affect Chinook salmon morethan bull trout (Section 3.3.4.1). Since bull trout redds are typically smaller than Chinook salmonredds (Stillwater Sciences 2006a), increases in the numbers of spawners could cause significantsuperimposition with as few as 30 Chinook salmon females, whereas superimposition is notpredicted to be significant for bull trout spawners until at least 150 female bull trout arespawning. However, bull trout egg burial depths range from 10 to 20 cm (4 to 8 in), and Chinooksalmon egg burial depths are typically greater than 20 cm (8 in) (DeVries 1997), so inter-specificsuperimposition is not considered to be a high risk for Chinook salmon either.3.4.2.2 FryBased on field measurements of gravel permeability (Stillwater Sciences 2006d) and applicationof a relationship between permeability and egg-to-emergence survival (Tagart 1976, McCuddin1977), incubation survival for Chinook salmon eggs is expected to be relatively low in CarmenBypass Reach. Increasing egg-to-emergent fry survival (e.g., by improved gravel quality) would28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board29

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportincrease the number of emergent fry, which would subsequently migrate to rear in the reservoir(since fry rearing habitat in the bypass reaches in limited). Overall, the model is sensitive toincubation mortality, and moderate increases in egg-to-emergence survival could result inincreases in smolt production.Habitat limits the abundance of fry in the bypass reaches (Stillwater Sciences 2006b). All earlyfry that do not find suitable habitat in the bypass reaches are assumed to migrate and rear in TrailBridge Reservoir. Data from rotary screw trapping in the Carmen Bypass Reach corroborate anearly fry migration of Chinook salmon, and direct observation snorkel surveys confirm relativelylow fry abundance in Lower Carmen and Smith bypass reaches (although fry are difficult toobserve [Stillwater Sciences 2006a]). Therefore, fry survival during migration to the reservoirstrongly affects smolt production.3.4.2.3 JuvenileThe carrying capacity of juveniles in the Carmen and Smith bypass reaches is a function of theamount of available habitat and the density of Chinook salmon that can occupy that space. Undercurrent conditions, habitat for juveniles is abundant in both bypass reaches. However, juvenileChinook salmon rearing in these reaches must share suitable habitat with juvenile cutthroat trout,rainbow trout, and bull trout (only in the Carmen Bypass Reach). The juvenile trout and char inthis habitat occur in high densities (> 1 fish/m 2 [10.8 fish/ft 2 ]), and are large enough (> 150 mm[5.9 in]) to prey upon juvenile Chinook salmon (~60 mm [2 in]). Observations during summerand winter snorkel surveys indicated that juvenile Chinook salmon rear in low densities (< 0.1fish/m 2 [0.1 fish/10.8 ft 2 ]). Therefore, it appears that despite the available habitat, most Chinooksalmon emigrate to Trail Bridge Reservoir to rear. Rotary screw trapping (in the Carmen BypassReach only) and snorkel survey results (in both reaches) indicate large pulses of fry emigrating inthe spring and summer, very few juveniles overwintering in the bypass reaches, and minimalsmolt production in the bypass reaches (Stillwater Sciences 2006a).3.4.3 All life-stages in Trail Bridge ReservoirTrail Bridge Reservoir provides abundant rearing habitat for all early life-stages of Chinooksalmon produced in the bypass reaches. Survival in the reservoir strongly affects smoltproduction (Table 3-7), and is influenced by factors such as stranding, entrainment, andpredation. A large number (> 10,000) of hatchery rainbow trout are released into Trail BridgeReservoir at sizes large enough to prey on Chinook salmon fry produced in the bypass reaches;hatchery rainbow trout have been observed preying on Chinook salmon fry in other lentic systems(e.g, Tabor et al. 2004), and in the McKenzie River (Firman et al. 2004).Chinook salmon fry are occasionally stranded by reservoir fluctuations in Trail Bridge Reservoir.During 31 surveys conducted in 2005, 25 dead spring Chinook salmon fry (progeny of hatcheryadult releases) were observed (Stillwater Sciences 2006e). The overall mortality rate attributableto stranding in the reservoir is not known, but is assumed to be a component of the 50% mortalityrate used for fry rearing life-stage in Trail Bridge Reservoir (in addition to predation mortality).Field studies are planned for spring 2006 to estimate total number of fish stranded during theperiod of greatest vulnerability (fry downstream migration).Smolt production from Trail Bridge Reservoir is also affected by downstream passage survival atTrail Bridge Dam. Current values in the model assume a high mortality rate (20%) relative to theliterature (e.g., Bell 1981, Stillwater Sciences 2006c). The modeled production of smolts from28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board30

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTrail Bridge Reservoir (~1,500) could not be directly corroborated by captures at the rotary screwtrap downstream of Trail Bridge Dam, since the trap was not operational year-round.Although the model estimates production of age 1+ smolts, rotary screw trap capturesdownstream of Trail Bridge Dam indicate that age 0+ fry also emigrate in the spring, and age 0+smolts (~8 months post emergence) emigrate in the fall. This is a genetic trait consistent withspring Chinook salmon life history in other basins (Healey 1991), and likely does not indicatehabitat limitations in the reservoir. The age 0+ Chinook salmon fry that emigrate decrease theproduction of smolts from Trail Bridge Reservoir; however, emigrating fry likely contribute tothe population downstream of Trail Bridge Dam.3.4.4 Resiliency to disturbanceThe spring Chinook salmon population in the Study Area is believed to be relatively resilient todisturbance. However, the model was not successful in accurately estimating recovery fromdisturbance for spring Chinook salmon, because factors such as adult migrant straying and lifehistorydiversity (e.g., age at adult migration) were not explicitly addressed. For example, if afish kill caused the complete failure of one year-class, model results indicate that up to 5generations would be required for the impacted year-class to recover. However, strays from otherspawning reaches in the basin could quickly re-colonize the Study Area. In addition, sincemature adults can return from the ocean at a variety of ages, a spawning population could be reestablishedin the first generation. Overall, short-term alterations in the amount or quality ofhabitat (e.g., physical habitat, food availability) at critical life-stages are not likely to cause longtermdamage to the Chinook salmon population. The Chinook salmon population is believed tobe resilient to disturbance in the Study Area based on:• Age structure of the returning adult population from age 3+ to age 6+,• Common for adults to stray,• High production of smolts relative to the adult population,• Spawning habitat in both the Carmen Bypass Reach and Smith Bypass Reach, and• Habitat supporting rearing to age 1+ smolts in both Trail Bridge Reservoir andthroughout the McKenzie River mainstem.3.5 Effects of Changes in Project Operations and/or Enhancements on BullTrout Population DynamicsBased on current bull trout population dynamics, conceptual and quantitative model resultsindicate that management actions taken to increase spawning or rearing habitat of bull trout, instream reaches or Trail Bridge Reservoir, are unlikely to increase the bull trout population.However, efforts to increase habitat for subadults/adults in Trail Bridge Reservoir, or potentiallyby providing safe access to and from Smith Reservoir or habitat downstream of Trail BridgeDam, could increase carrying capacity, which would result in an increase of the adult population.If mortality of the adult population related to angling and poaching were reduced (e.g., viaincreased law enforcement), the adult population would increase. Reductions in adult mortalityby any means (e.g., reducing emigration and/or poaching) would result in a larger adultpopulation, and a reduction in the subadult population (because of the shared habitat).Although the adult population would not be expected to increase, an increase in juvenile bull troutcould be obtained by large woody debris enhancements in Carmen Bypass Reach or SweetwaterCreek, or lower water temperatures in the Smith Bypass Reach (which could only be achievedwith hypolimnetic releases at Smith Dam).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board31

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3.5.1 Instream flowsTo evaluate the effect of increasing instream flows over current base flows in the Carmen BypassReach, suitable habitat areas estimated in the Aquatic Habitats and Instream Flows study(Stillwater Sciences 2006b) were used as values for the available habitat parameters in the model.The parameter values used for modeling are provided in Appendix D. (Note that the flow/habitatrelationships are based on the flows tested during the Aquatic Habitats and Instream Flows study,and may not represent the flows that maximize habitat for any life-stage). The habitat criteriamapping method used in the Aquatic Habitats and Instream Flows study had a measured error ofabout ±30%. The sensitivity analysis addressed this error by running scenarios where each valuewas increased or decreased. Although bull trout do not currently spawn or rear in the SmithBypass Reach, increased flows were considered in conjunction with a hypolimnetic release fromSmith Dam (the feasibility of which has not been explored) to decrease stream temperatures andmake habitat suitable for all life-stages of bull trout.3.5.1.1 Carmen Bypass ReachIf instream flows were increased to maximize available habitat for all life-stages in the CarmenBypass Reach (around 205 cfs based on the flows measured in the Aquatic Habitats and InstreamFlows study), the carrying capacity would increase for most life-stages except subadults/adults.However, the overall population would not be expected to increase unless the carrying capacityfor subadult/adult bull trout in Trail Bridge Reservoir was also increased.Spawning habitat under current flows is adequate to “seed” the Carmen Bypass Reach with moreemergent fry than can be supported at subsequent life-stages. While increasing flows during thespawning season (fall) to 205 cfs would increase available spawning habitat, the number of fryproduced are currently limited by early fry habitat, rather than spawning habitat. Based onmodeling results, early fry rearing habitat limits the production of juvenile bull trout from theCarmen Bypass Reach. However, early fry rearing habitat peaks at 205 cfs, which is the currentbase flow during the early fry rearing period (spring). Increasing flows in the Carmen BypassReach during spring would likely decrease the carrying capacity for early fry, resulting in fewerjuveniles from the Carmen Bypass Reach (Stillwater Sciences 2006b).Habitat for late fry did not increase significantly with increased flow (Stillwater Sciences 2006b),though slightly more habitat was observed at 205 cfs than at lower or higher flows. Habitat forlate fry was far more abundant than habitat for early fry at all flows, and is unlikely to limitproduction of bull trout from the reach.Habitat for juvenile bull trout was not found to increase significantly with increased flow(Stillwater Sciences 2006b), though slightly more habitat was observed at 205 cfs than at lower orhigher flows. The production of juveniles in the Carmen Bypass Reach is currently limited by theproduction of early fry, and until this “bottleneck” is addressed, increases in juvenile habitat willnot increase juvenile production (though overall, the population is limited by adult habitat).No subadult or adult habitat was mapped in the Carmen Bypass Reach at any flow, primarilybecause increased flows (up to 345 cfs) do not result in adequate increases in water depth(Stillwater Sciences 2006b) based on the habitat criteria selected by the IFCT. This finding iscorroborated by PIT tag analysis and snorkel surveys, both of which rarely detected subadults oradults in the Carmen Bypass Reach outside of the spawning season (Stillwater Sciences 2006a).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board32

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3.5.1.2 Smith Bypass ReachNo bull trout have been observed in the Smith Bypass Reach during snorkel or spawning surveys,although two bull trout were detected by the PIT tag antenna (an adult in late October, and ajuvenile bull trout in mid-summer 2004) (Stillwater Sciences 2006a). The PIT tag antenna waslocated at the downstream end of the Smith Bypass Reach, and the distance that the bull troutmoved upstream is unknown. Maximum summer water temperatures were regularly over 16°C(60°F) in the Smith Bypass Reach, as described in the Water Quality report (Stillwater Sciences2006d). The probability of juvenile bull trout occurrence is relatively low (less than 50%) instreams with maximum daily temperatures above approximately 14–16°C (57–60°F) (Dunham etal. 2003). Based on the conceptual model for bull trout, even if bull trout can persist in watertemperatures over 16°C (60°F), they are likely at a competitive disadvantage with rainbow troutand cutthroat trout, both of which occur in the Smith Bypass Reach.Artificially cooling the water in the Smith Bypass Reach (e.g., hypolimnetic release, chillers,pumping ground water) would be required to maintain suitable water temperatures for bull troutrearing. Smith Reservoir is temperature-stratified during summer, and below about 3 m (10 ft)depth, temperatures remain below 12°C (53°F), even during the summer. If hypolimneticreleases (greater than 18 m [60 ft] deep) were provided from Smith Reservoir into the SmithBypass Reach, cooler temperatures could be maintained in the Smith Bypass Reach to supportbull trout. Based on water temperature modeling (Stillwater Sciences 2006d), a hypolimneticrelease of 45 cfs between mid-June and mid-September would result in summer temperatures inthe Smith Bypass Reach below 12°C (53°F) for the entire year.Prior to the construction of Smith Dam, the Smith River typically had summer flows less than 20cfs (Stillwater Sciences 2006d), and water temperatures were likely greater than 12°C (53°F)(Stillwater Sciences 2006h). Surface waters in Smith Reservoir during summer are > 12°C(53°F), so only a hypolimnetic release from Smith Reservoir would be capable of decreasingwater temperatures in Smith Bypass Reach to temperatures suitable for bull trout, which likelydid not occur historically during summer. Water temperatures during the fall spawning seasonare currently low enough to allow spawning and successful incubation. However, summer watertemperatures appear to preclude the use of this reach by bull trout, as observed in other rivers(Dunham et al. 2003).Although the feasibility of a hypolimnetic release (or chillers, or pumping groundwater) has notbeen explored for Smith Dam, the population model was run assuming a minimum flow in theSmith Bypass Reach of 50 cfs (current base flow plus hypolimnetic release to achieve suitablewater temperatures for bull trout rearing) between mid-June and mid-September, and regulatedbase flows under current operations (i.e., no releases at Smith Dam) the remainder of the year.The model also assumed that 8 females would spawn in the Smith Bypass Reach. The modelparameters that were used, in addition to the default values used to model current conditions, areprovided in Table D-4.Increasing juvenile production from the Smith Bypass Reach would not increase the adultpopulation. Because production of juveniles from Carmen Bypass Reach and Sweetwater Creekare not currently limited by the number of female spawners, juveniles are not predicted to declinein these reaches with increased spawning in Smith Bypass Reach. Assuming current base flowsin Smith Bypass Reach, spawning habitat is limited to the production of approximately 8,000eggs. However, since subsequent life-stages (early fry and juveniles) are limiting, increasinginstream flows to increase available spawning habitat would have no effect on production.Production of juveniles from the Smith Bypass Reach is limited by available habitat for early fry,28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board33

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportand then by available habitat for juveniles. Both of these life-stages show a peak in availablehabitat at 7 cfs, which is a lower flow than currently occurs during most of the early fry andjuvenile rearing periods, and which is lower than the minimum flows required to reduce watertemperatures to levels suitable temperatures for bull trout. The model estimates that withhypolimnetic releases from Smith Dam, over 1,000 juveniles could be produced from this reach.Although the potential increase in juvenile production from Smith Bypass Reach wouldeffectively double potential juvenile-to-subadult recruits in the reservoir, no increase in the adultpopulation is expected, because adult habitat would still be limiting in Trail Bridge Reservoir.3.5.2 Large woody debris additionsLarge woody debris enhancements can increase the amount of available habitat and the density ofbull trout that can occupy that space, by increasing habitat complexity (e.g., Gowan and Fausch1996, Dambacher and Jones 1997). During Summer 2005, as part of a collaborative effort withEWEB and other parties, the USDA Forest Service added wood to approximately 80% of thelower Carmen Bypass Reach.The Aquatic Habitats and Instream Flows study (Stillwater Sciences 2006b) found that existinglarge woody debris already in the reach increased habitat for all early life-stages of bull trout inthe Carmen Bypass Reach, at all flows assessed. In the vicinity of large woody debris, a 50 to100% increase in the amount of available habitat generally occurred, compared with areaswithout large woody debris. To determine the potential effect of the USDA Forest Service’slarge woody debris enhancement on current bull trout population dynamics, the input values foravailable habitat in the reach were increased based on the increase observed in the AquaticHabitats and Instream Flows study (Stillwater Sciences 2006b), and adjusted by the areaenhanced (Table D-6).Based on the population dynamics model, the USDA Forest Service’s 2005 large woody debrisenhancement project increased rearing habitat for early fry by more than 100%, and juvenileproduction from the Carmen Bypass Reach by more than an estimated 300 individuals. If largewoody debris were added to Sweetwater Creek in amounts similar to those added to the CarmenBypass Reach, and if similar increases in available habitat resulted, then juvenile production fromboth reaches is estimated to increase by more than 500 juveniles for a total of nearly 1,000 age 2+juveniles.However, the overall number of adults in the Study Area is not expected to increase with largewoody debris enhancements, because the enhancements will not increase subadult/adult habitat.However, protecting high levels of production age 2+ juveniles are important to maintaining theresiliency of the current population (see Section 3.3.5).3.5.3 Spawning gravel augmentationBecause subsequent life-stages (early fry) are limiting production from existing spawning areas inall three reaches in the Study Area, gravel augmentation to increase available spawning habitatwould not affect bull trout production. However, in the Smith Bypass Reach, where the amountof current spawning habitat is low, gravel augmentation may increase the opportunities of femalestrying to locate suitable spawning habitat (which still would have no effect on overallpopulation), assuming that water temperatures were suitable.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board34

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3.5.4 Trail Bridge Reservoir habitat enhancementsBased on the conceptual and quantitative population modeling, the bull trout population in theStudy Area is currently limited by available habitat for subadults and adults. If habitat in TrailBridge Reservoir was enhanced to increase complexity (e.g., large woody debris, brush bundles,boulders), the density of subadults and adults might increase. Gowan and Fausch (1996) foundthat large woody debris enhancements in streams successfully increased the adult populations ofbrook, brown, and rainbow trout, though no similar field data exists for lake or reservoir habitator for bull trout specifically. For habitat complexity to increase density, food is also assumed tobe sufficient and not a limit to the adult population. Food availability in itself may also increasedensity of adult bull trout (and thus population size) if territory size decreases as prey abundanceincreases, as has been observed in other salmonids (Grant et al. 1998).The possibility that bull trout are food-limited in Trail Bridge Reservoir was evaluated byexamining a bioenergetic analysis from Lake Billy Chinook (Beauchamp and Van Tassell 2001).The bull trout population in Lake Billy Chinook is assumed to be an appropriate surrogate for thebull trout population above Trail Bridge Dam, and that although kokanee salmon occur in LakeBilly Chinook but not in the Study Area, Chinook salmon can be considered a surrogate preyspecies.Under current conditions of Chinook salmon production in the Study Area, and with annualhatchery trout stocking, food does not appear to be limiting in Trail Bridge Reservoir for bulltrout subadult and adult life-stages (Table 3-8). Based on an assessment of fish prey consumptionconducted on bull trout in Lake Billy Chinook (Beauchamp and Van Tassell 2001), the per-capitanumber and size range of fish prey eaten by bull trout can be estimated (Table 3-8). The juvenilelife-stage of bull trout may require more food in the size category of the Chinook salmon fry thanis available, and food availability could begin to limit growth at this life-stage, but theinteractions between food supply and hatchery trout in the Study Area are poorly understood.Based on the analysis of potential consumption by hatchery-stocked rainbow trout of Chinooksalmon fry, their consumption alone could deplete the stock of Chinook salmon fry (see Section3.5.6), and thus rainbow trout would compete for food resources with juvenile and subadult bulltrout. However, the rainbow trout are likely also a potentially important food supply for adultbull trout, assuming adult bull trout will eat fish as large as half of their length. If adult bull troutpreferred to eat juvenile Chinook salmon over hatchery rainbow trout, food limitation would belikely. It is notable that the maximum lengths of adult bull trout in Lake Billy Chinook aregreater than adult bull trout in Trail Bridge Reservoir at the same age, also suggesting thepotential for food limitation in Trail Bridge Reservoir. In summary, although food does notappear limiting for subadults or adults, the interactions between hatchery fish, Chinook salmonfry, and bull trout juveniles are poorly understood, and thus food limitations may exist.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board35

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 3-8. Bull trout consumption of fish in Lake Billy Chinook (based on Beauchamp and VanTassell 2001) per individual and potential consumption of fish in Trail Bridge Reservoir(based on Stillwater Sciences 2006a).Bulltrout size(mm)Numberof bulltrout inTrailBridgeReservoirMeasured percapitaconsumption inLake BillyChinook(fish/year)200–300 456 25 (< 100 mm)300–450 26 36 (< 150 mm)> 450 a 85 33 (< 350 mm)Estimated percapitaconsumption inTrail BridgeReservoir(fish/year)25 Chinooksalmon fry36 Chinooksalmon juveniles33 bull trout orrainbow troutEstimated totalconsumption inTrial BridgeReservoir(fish/year)11,400 Chinooksalmon fry930 Chinooksalmon juveniles2,800 hatcherytrout or bull troutCurrent foodavailability inTrail BridgeReservoir(total numberof fish)> 20,000emergentChinook salmonfry> 1,500Chinook salmonjuveniles> 10,000hatchery troutand bull trouta Assumed that bull trout > 450 mm eat predominantly larger prey (e.g., bull trout juveniles and hatchery rainbow trout),although it is possible the smaller prey (e.g., Chinook salmon juveniles) are also consumed.Based on this simplistic analysis, food is not limiting the adult bull trout population in TrailBridge Reservoir under current conditions. If adult density were increased to 0.133 fish/mshoreline, which has been observed in some systems with abundant bull trout (Lake BillyChinook), the adult population upstream of Trail Bridge Dam could theoretically increase tonearly 640 adults. Although it is not known if densities similar to those observed in Lake BillyChinook could ever be achieved in Trail Bridge Reservoir, maintaining or increasing foodavailability and increasing habitat complexity for adults appear to be the actions most likely ofincreasing population size upstream of Trail Bridge Dam.3.5.4.1 Adult mortalityBull trout adult mortality in the Study Area was estimated to be about 20% annually (StillwaterSciences 2006a), which includes losses from natural causes, poaching, emigration, etc (the rate ofmortality from each source is unknown). The current adult population is composed of age 4+ toage 7+ individuals (Stillwater Sciences 2006a), which is consistent with estimates of high annualmortality or emigration. Angler surveys and Oregon police reports indicate that angling pressure(e.g., use of bait) and poaching of bull trout occur in the Study Area (Stillwater Sciences 2006i).If mortality of the adult population related to angling and poaching were reduced (e.g., viaincreased law enforcement), the adult population would increase. Reductions in adult mortalityby any means (e.g., reducing emigration and/or poaching) would result in a larger adultpopulation, and a reduction in the subadult population (because of the shared habitat). In contrastto the Trail Bridge population, many bull trout populations have long-lived individuals (>7 yearsold) (Hagen and Baxter 1992). A larger adult population would increase the resiliency of thepopulation by increasing the number of individuals of spawning age, as well as the number ofindividuals from separate cohorts.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board36

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3.5.5 Fish Passage at Trail Bridge DamBased on PIT tag detections (Stillwater Sciences 2006c), if passage facilities were provided atTrail Bridge Dam, a portion of bull trout subadults and adults would pass downstream over thedam during the fall after spawning, and return in the early summer. Regardless of the response ofthe population to accessing additional habitat, populations upstream and downstream of TrailBridge Dam would be expected to benefit from genetic connectivity, the expression of multiplelife histories (e.g., fluvial or adfluvial), and the opportunity to migrate downstream with preymigrations (e.g., Chinook smolts). These benefits are discussed in the Aquatic HabitatConnectivity report (Stillwater Sciences 2005j) and were not modeled.Access to habitat in the mainstem McKenzie River downstream of Trail Bridge Dam couldincrease the overall amount of adult habitat for the upstream population, and thus the populationsize could increase. If, however, habitat conditions for adults downstream of Trail Bridge Damare not as suitable as those upstream of the dam (e.g., increased angling pressure, less foodavailability) or if the habitat is already occupied, the health of the population upstream of TrailBridge Reservoir could be reduced (i.e., if the bull trout in Trail Bridge Reservoir are a sourcepopulation, and the population downstream of Trail Bridge Dam is stable or in decline). Twoscenarios were modeled: 1) subadult/adult habitat downstream of Trail Bridge Dam is unlimited,and 2) subadult/adult habitat downstream of Trail Bridge Dam is currently saturated by thespawning population from Ollalie and Anderson creeks. Both scenarios assumed that there wasno mortality during downstream and upstream passage (e.g., screened turbine, bypass facility, andfish ladder).In the first scenario (no habitat limitations for subadult/adult bull trout), the model predicts anincrease of the subadult/adult population to nearly 800 individuals before habitat for early fry inthe Carmen Bypass Reach and Sweetwater Creek would limit additional increases in thepopulation. Under this scenario, most of the fish (~700) would be assumed to migrate from TrailBridge Reservoir after the juvenile rearing stage, returning only to spawn in Carmen BypassReach or Sweetwater Creek. In the second scenario (habitat is limited for subadult/adult bulltrout), the model predicts no increase of the subadult/adult population, unless bull trout from TrailBridge Reservoir competitively displace bull trout produced from Ollalie and Anderson creeks.To assess the reasonability of the scenario that habitat downstream of Trail Bridge Dam is notlimited, production from Anderson and Ollalie creeks was modeled. Based on averageproduction estimates measured at a rotary screw trap operated by the USDA Forest Service inAnderson Creek, an average of about 10,000 bull trout fry, and around 470 juveniles are producedeach year from Anderson Creek. Ignoring production from Ollalie Creek, and from the TrailBridge population, and assuming similar survival rates used to model bull trout above TrailBridge, over 700 spawning adults would be predicted. In fact, the highest redd count forAnderson Creek and Ollalie Creek combined was 94 in 1997, indicating at least 188 adults (94females, 94 males) returned to spawn. Because the actual number of returning adults differs fromthe 700 predicted by the model, either adult habitat (food availability and/or space) is limitedbelow Trail Bridge Dam, or survival of adults is lower in the mainstem McKenzie River than wasestimated for the Trail Bridge population. For example, if mortality from angling and othersources in the mainstem were as high as 70% annually for adults, the number of returning adultswould be predicted to be around 250, which is consistent with peak redd counts.Of the 16 PIT-tagged juvenile, subadult, and adult bull trout that migrated downstream in 2004and 2005, two adults were detected at the spawning channel, indicating that there is some suitablehabitat downstream, or that these individuals were able to out-compete adults already occupying28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board37

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportthat habitat. It appears that neither scenario is completely accurate; most likely additional adulthabitat is available, but not unlimited. It also appears that with fish passage at Trail Bridge Damadditional environmental factors, such as adult mortality in the mainstem, could exhibit a stronginfluence on the bull trout population. With continued monitoring, there should be additionalopportunities to detect fish that have found suitable habitat downstream.3.5.6 Fish passage at Smith DamIf upstream fish passage facilities were provided at Smith Dam, an adult bull trout populationwould presumably attempt to establish in Smith Reservoir (or it could be seeded with outplantedfry). Bull trout production from the upper Smith River (the Smith River upstream of SmithReservoir), and the potential adult population in Smith Reservoir, were modeled separately fromthe Trail Bridge population, based on habitat in the Smith Reservoir and Smith River, andassuming a starting population of 100 subadult/adult bull trout (Table D-5).Bull trout require a narrow range of cold-water temperatures for all of their life-stages (Buchananet al. 1997). Water temperatures in the upper Smith River are currently higher than the preferredrange for bull trout during their spawning, fry, and juvenile life-stages (Figure 3-11). To modelthe scenario with passage at Smith Dam, spawning was nonetheless assumed to occur in theSmith River upstream of Smith Reservoir, and all late fry were assumed to migrate from upperSmith River in June, as temperatures increase (Figure 3-11). No late fry or juvenile use of upperSmith River was modeled.Based on the analysis, Smith Reservoir and upper Smith River could not support a population ofbull trout. Without rearing habitat in the upper Smith River, all rearing of late fry and juvenileswould occur in Smith Reservoir, where survival is estimated to be very low (as it is in TrailBridge Reservoir), based on potential predation from releases of hatchery trout, and any adult bulltrout that would be in the reservoir. A population of bull trout in Smith Reservoir would be verysensitive to, and limited by, survival of fry and juveniles. The only scenario that maintained astable population required a value for fry survival in Smith Reservoir considered to beunrealistically high (> 20%); in that scenario, 13 subadults and adults were supported in thereservoir based on fry and juvenile bull trout rearing in Smith Reservoir.Although a self-sustaining population of bull trout could not be supported in Smith Reservoirbased on habitat mapping (Stillwater Sciences 2006b) the Smith Reservoir has the potential toprovide adult bull trout habitat. If passage facilities were provided at Smith Dam, subadult andadult bull trout from Trail Bridge Reservoir could migrate to Smith Reservoir during the winter–summer period, returning downstream during fall to spawn in the Carmen Bypass Reach orSweetwater Creek. Radio-tagged bull trout in other systems have been observed to migratethroughout a basin, even passing through warmer reaches, to access suitable habitat (Scholz et al.2005). If subadult and adult bull trout used Smith Reservoir seasonally as additional foraginghabitat, the overall subadult/adult population could increase by an estimated 108 individuals,effectively doubling the size of the current population upstream of Trail Bridge Dam.3.6 Effects of Changes in Project Operations and/or Enhancements onSpring Chinook SalmonBased on current population dynamics, conceptual and quantitative model results indicate that,actions to increase spawning habitat and/or spawning habitat quality in the bypass reaches arelikely to increase Chinook salmon smolt production from the Study Area, particularly in the28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board38

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSmith Bypass Reach. Actions to decrease mortality of all life-stages of Chinook salmon in TrailBridge Reservoir are also predicted to increase smolt production.3.6.1 Instream flowsTo evaluate the impact of increasing instream flows over current base flows in the CarmenBypass Reach and Smith Bypass Reach, suitable habitat area estimates from the Aquatic Habitatsand Instream Flows study (Stillwater Sciences 2006b) were used as values for habitat areaparameters in the model. The habitat values used for modeling were based on maximizingavailable habitat for each life-stage (Table E-3), based on the flows measured in the AquaticHabitats and Instream Flows study. Unlike other instream flows methods, by using the habitatcriteria mapping method (see Aquatic Habitats and Instream Flows study) it was possible toevaluate measurement error (approximately ±30%). The sensitivity analysis conducted on allparameters addressed this error by running scenarios where each value was increased ordecreased. Habitat areas for the life-stages that highly influence the model (e.g. spawninghabitat) warrant additional consideration, in light of the associated error with the original inputvalue used.3.6.1.1 Carmen Bypass ReachIn general, increasing habitat for fry or juveniles has little effect on the production of smolts.Based on the flows evaluated in the instream flow analysis (Stillwater Sciences 2006b),maximum available habitat for all life-stages in the Carmen Bypass Reach occurs at about 205cfs. (Note that the flow/habitat relationships are based on the flows tested during the AquaticHabitats and Instream Flows study). However, because of the abundant rearing habitat forChinook salmon in Trail Bridge Reservoir, increasing habitat for fry or juveniles has little effecton the production of smolts (i.e., 23 additional smolts). The exception is spawning habitat;increasing available spawning habitat by increasing flows to 205 cfs results in more emergent fryand, whether they rear in Carmen Bypass Reach or in Trail Bridge Reservoir, smolt productionincreases (Table 3-9). However, smolt production and flow increases are not linear; flows greaterthan 205 cfs result in a decrease in available spawning habitat, and thus a decrease in smoltproduction (Table 3-9).Table 3-9. Estimated changes in Chinook salmon smolt production with increasing instreamflows in the Carmen Bypass Reach.Estimated spawning habitat Total estimated smoltFlow (cfs)availability 1production from Trail Bridgem 2 ft 2 Reservoir160 212 2,282 1,252205 289 3,111 1,449320 237 2,551 1,322345 203 2,185 1,2261 Estimated for the Chinook salmon spawning guild; 145 m 2 were added to the estimate for available habitat in CarmenBypass Reach (habitat unit #1), which was not included in the habitat mapping study.3.6.1.2 Smith Bypass ReachIn general, increasing habitat for fry or juveniles has little effect on the production of smolts. Ifinstream flows were increased to maximize available habitat for all life-stages of Chinook salmonin the Smith Bypass Reach (around 50 cfs during summer and winter), the carrying capacity28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board39

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportwould increase for most life-stages. However, because of the abundant rearing habitat forChinook salmon in Trail Bridge Reservoir, increasing habitat for fry or juveniles has little effecton the production of smolts (i.e., 10 additional smolts). As in the Carmen Bypass Reach, theexception is spawning habitat. Increasing available spawning habitat results in more emergent fryand, whether they rear in the Smith Bypass Reach or Trail Bridge Reservoir, smolt productionincreases. Increases in spawning habitat were observed at 20 and 120 cfs, but not at 50 or 85 cfs(Table 3-10), apparently due to available spawning habitat shifting from the thalweg at the lowerflows to channel margins at the higher flows.Table 3-10. Estimated changes in Chinook salmon smolt production with increasing instream flowsin the Smith Bypass Reach.Estimated spawning habitat Total estimated smolt production from Trailavailability aBridge ReservoirFlow (cfs)m 2 ft 2 Assuming small Assuming normal sizeredds (0.9 m 2 ) b redds (5.4 m 2 ) c7 7 75 1,252 72120 29 312 2,157 1,12950 20 215 1,838 99185 20 215 1,838 991120 89 958 4,027 1,654a Estimated for Chinook salmon spawning guild; 7 m 2 were added to the estimate for available habitat in Smith BypassReach (habitat units #1–4), which were not included in the habitat mapping study.bBased on total station survey of redd dimensions in Smith Bypass Reach.cBased on total station survey of redd dimensions in Carmen Bypass Reach.These estimates were made under two assumptions: (1) that returning spawners will use the SmithBypass Reach in increasing numbers relative to the Carmen Bypass Reach, if spawning habitatincreases in the Smith Bypass Reach, and (2) as spawning habitat increases, female Chinooksalmon will continue to build the unusually small redds currently observed in Smith BypassReach (0.9 m 2 [9.7 ft 2 ]). However, as spawning habitat increases, female Chinook salmon wouldlikely construct redds that are proportionately larger, approximating the size currently observed inCarmen Bypass Reach (5.4 m 2 [58.1 ft 2 ]). In this case, spawning habitat would remain limiting,and production would not increase as dramatically (Table 3-10).3.6.2 Large woody debris additionsAdding large woody debris is one approach to increasing available habitat in Carmen BypassReach and Smith Bypass Reach. Large woody debris additions increase habitat complexity,which is favorable for Chinook salmon fry and juveniles. During Summer 2005, in collaborationwith EWEB and other parties the USDA Forest Service added wood to approximately 80% of thelower Carmen Bypass Reach.The Aquatic Habitats and Instream Flows study (Stillwater Sciences 2006b) found that exisitinglarge woody debris already in the reach increased habitat for spawning, fry, and juvenile lifestagesof Chinook salmon in the Carmen Bypass Reach, at all flows assessed. In the vicinity oflarge woody debris, a 50 to 100% increase in the amount of available habitat was estimated,compared with areas without large woody debris. To determine the potential effect of the USDAForest Service’s large woody debris enhancement on current Chinook salmon populationdynamics, the input values for available habitat in the reach were increased, based on the increase28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board40

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportobserved in the Aquatic Habitats and Instream Flows study, as adjusted by the area enhanced(Table E-5).Based on model predictions, the USDA Forest Service’s 2005 large woody debris enhancementproject increased available habitat for spawning and rearing life-stages of Chinook salmon, andincreased overall smolt production from Trail Bridge Reservoir by an estimated 300 smolts. Iflarge woody debris were added to Smith Bypass Reach in amounts similar to those in CarmenBypass Reach, and if similar increases in available habitat resulted, then modeled overall smoltproduction from Trail Bridge Reservoir increases by nearly 500 smolts. Most of the increase insmolt production would result from increased spawning habitat in both reaches.3.6.3 Spawning gravel augmentationBased on current population dynamics, actions to increase spawning habitat areas and/or qualityin the bypass reaches are likely to increase Chinook salmon smolt production in the Study Area,particularly in the Smith Bypass Reach, as described above. Gravel augmentation resulting inincreased spawning habitat in the Carmen Bypass Reach could increase smolt production slightly.However, if gravel additions resulted in higher quality spawning gravel and an increase in egg-toemergencesurvival, production of smolts could increase significantly. For example, adding 100m 2 (1,076 ft 2 ) of spawning habitat alone would result in an estimated increase of almost 200smolts, but if accompanied by a 20% increase in egg-to-emergence survival (based on betterspawning gravel quality), the estimate increases to over 1,000 smolts.In the Smith Bypass Reach, spawning habitat is currently limiting production in that reach.Increases in available spawning habitat in the Smith Bypass Reach are predicted to result in largeincreases in smolt production. Because rearing habitat for fry and juveniles in the Smith BypassReach is greater than in the Carmen Bypass Reach under current conditions, and because theSmith Bypass Reach currently has very little spawning habitat, increasing spawning habitat in theSmith Bypass Reach has a greater influence on the population than increases in the CarmenBypass Reach. For example, if available spawning habitat were increased in the Smith BypassReach by 100 m 2 (1,076 ft 2 ), smolt production from above Trail Bridge Dam would increase byover 500 smolts (assuming redd size increased), even without an accompanying increase in gravelquality.Increases in spawning habitat were observed at 20 and 120 cfs (Table 3-10), apparently due toavailable spawning habitat shifting from the thalweg at the lower flows to channel margins at thehigher flows. The placement of gravel could alter the relationship between available spawninghabitat and instream flows. Any gravel augmentation program should consider instream flows,and may benefit from enhancements that are deliberately designed to target a specific range offlows.3.6.4 Trail Bridge Reservoir3.6.4.1 Hatchery trout predationHatchery trout are significant predators on native salmonids (Swartzman and Beauchamp 1990).Currently, ODFW annually stocks Trail Bridge Reservoir with over 14,000 rainbow trout that areover 200 mm (8 in) FL. Each of these trout could potentially consume Chinook salmon fry orjuveniles. Currently, no data document the diet of hatchery trout stocked into Trail BridgeReservoir. However, hatchery trout stocked in the mainstem McKenzie River were found to28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board41

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportconsume Chinook salmon fry at Leaburg Dam, mostly between May and June (Firman et al.2004). Presumably, as fry grow into juveniles, they become less susceptible to predation. Thenumber of fry found in trout stomachs varied from 0 to 5 fish (Firman et al. 2004). Firman et al.(2004) estimated that between 48,580 and 161,933 Chinook salmon fry were consumed byhatchery trout in the mainstem McKenzie River in 2003, based on the equation:The total number of Chinook salmon consumed = T*P*(24/G)*DWhereT = total number of hatchery trout present (including a 37% reduction from anglers, based oncreel surveys on the McKenzie River)P = percentage stomach content samples that contained Chinook salmonG = gut residence time in hours (3–10 hours based on controlled experiments)D = total number of days that trout fed on Chinook salmon (62)Following this approach for the number of hatchery fish stocked into Trail Bridge Reservoir, andusing the same estimates for variables P, G, and D, the number of Chinook salmon consumed byhatchery trout is between 12,000 and 40,000 each year in Trail Bridge Reservoir, assuming levelsof predation are similar. Even assuming that predation rates in a reservoir will be far less than ina river (~12,000 each year), the potential for predation mortality from hatchery fish appears to besignificant. Based on these estimates, if mortality from hatchery trout were reduced by 30% (e.g.,less stocking, or stocking later in the season after Chinook salmon have grown), the number ofsmolts produced is estimated to increase dramatically (5,500), even with the current estimatedmortality from bull trout predation (Section 3.5.4).3.6.4.2 Entrainment and strandingIncreases in habitat complexity or reducing entrainment mortality (see Section 3.6.5), are alsoapproaches to increasing Chinook salmon survival in Trail Bridge Reservoir, and are alsopredicted to increase smolt production. Although the current magnitude of stranding in TrailBridge Reservoir is unknown, decreasing mortality from stranding by any amount would alsoincrease smolt production.3.6.5 Fish passage at Trail Bridge DamThere are many alternatives to provide both upstream and downstream fish passage at TrailBridge Dam. All modeling conducted for this report assumes volitional passage at Trail BridgeDam (e.g., fish ladder) with no associated mortality or delay. Downstream passage was modeledbased on the current conditions; whereby downstream migrating fish pass through the TrailBridge Turbine or spillway (with an assumed mortality rate of 20%). Downstream fish passagefacilities at Trail Bridge Dam could decrease mortality of fry, juvenile, and smolt Chinooksalmon migrating from the reservoir. If entrainment mortality is reduced to approximately 1% byuse of NMFS criteria screens at Trail Bridge Turbine, or guiding fish to an alternate downstreampassage route, smolt production would increase from current numbers by an estimated 300smolts.Although Chinook salmon currently rear in Trail Bridge Reservoir for up to one year,downstream passage facilities could improve the ability of Chinook salmon to migrate from TrailBridge Reservoir. If the number of fish leaving Trail Bridge Reservoir as fry increases, theoverall production of smolts from the reservoir would decrease, and similarly fewer juvenileChinook salmon would be potential prey for bull trout (although more of the subadult and adult28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board42

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportbull trout could migrate downstream as well, increasing predation in the McKenzie River belowthe project). Presumably, a proportion of the Chinook salmon that would migrate as fry wouldrear successfully to smolts in the mainstem McKenzie River.3.6.6 Fish passage at Smith DamIf fish passage facilities were provided at Smith Dam (e.g., fish ladder), presumably adultChinook salmon would migrate to Smith Reservoir from the Smith Bypass Reach. Theproduction from the upper smith river (the Smith River upstream of Smith Reservoir), and thepotential adult population in Smith Reservoir, were modeled assuming that 80% of the currentspawning population in the Smith Bypass Reach would migrate upstream to the upper SmithRiver (Table E-6), with no assumed mortality or delay associated with fish passage facilities.Spawning habitat in the upper Smith River is adequate to support a spawning population of nearly14 females. However, based on the survival of subsequent life-stages, a spawning population offewer than 5 is predicted. Fry habitat, and then juvenile habitat, limits rearing potential in theupper Smith River, and most rearing would occur in the Smith Reservoir, where fry and juvenilesurvival strongly affect estimated production. Based on the values estimated for Trail BridgeReservoir, over 250 smolts would be produced from Smith Reservoir. Predation from bull trout(assuming they had access along with Chinook salmon), introduced hatchery fish, and fromnative trout, would be expected to be high (Tabor et al. 2004). The ultimate increase in smoltproduction with fish passage at Smith Dam is predicted to be slightly over 200 smolts, includingan assumed 10% mortality of fish migrating from Smith Reservoir (regardless of passage atspillway, or Smith intake). If downstream fish passage facilities were provided at Smith Damthat could decrease mortality to 1%, overall smolt production is predicted to increase byapproximately 10 additional smolts.3.7 Carmen-Smith Spawning ChannelBased on population modeling, spring Chinook salmon rear briefly in the Carmen-SmithSpawning Channel before migrating to the mainstem McKenzie River. Under current conditions,the spawning channel has a capacity for over 175 spawning females, although currently, abouthalf that many use it (Stillwater Sciences 2006a). The spawning channel has abundant spawninghabitat, and currently is capable of producing over 250,000 emergent fry. The current productionis based on a gravel augmentation that occurred during July 2005. Presumably, habitat conditionswill decline over time, and the amount, and quality, of spawning habitat will be reduced.Although reductions in spawning habitat would not reduce smolt production, fry production ispredicted to be around 130,000, with a 50% decline in available habitat, and a 50% reduction insurvival to emergence. However, the carrying capacity for fry limits rearing in the spawningchannel, although available habitat for juveniles is more limiting than for fry rearing (Figure 3-9).The model estimates smolt production (~65 smolts under current conditions), but the productionof fry from the spawning channel (or from habitat upstream of Trail Bridge Dam) are also ofvalue to the population.The production of smolts from fry emigrating from the spawning channel was not directlymodeled, because the habitat in the mainstem McKenzie River where smolts would rear isdownstream of the Study Area. Explicitly modeling smolt production from the migrant fry wouldrequire populating the model with habitat and survival data from the mainstem McKenzie River,which are currently unavailable. However, assuming a lower estimate of emergent-fry-to-smoltsurvival (1%) than was used in the Trail Bridge Reservoir model, and using the same survival28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board43

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportrates for fry to smolt (7.2%) assumed for the Chinook salmon population in Trail BridgeReservoir (Table E-7), the production of fry from the spawning channel accounts for an estimated2,700 smolts in the mainstem McKenzie River.The bull trout modeling did not include the Carmen-Smith Spawning Channel, although bull trouthave been observed to spawn and rear there (Stillwater Sciences 2006a). Based on ODFW andUSFWS decisions, bull trout adults were removed from the spawning channel and transferredupstream of Trail Bridge Dam in Fall 2003 and 2004. However, it is not known if this practicewill be repeated.3.7.1 Sensitivity analysisThe results of the sensitivity analysis conducted on the Chinook salmon model at the Carmen-Smith Spawning Channel, under current conditions, indicated that the Chinook salmon populationis most strongly influenced by the model parameter “marine survival of smolts to adults” (Tables3-11 and G-2). While this parameter strongly affects model results, this study does not addressmarine conditions, and the smolt survival parameter is only included in the model to allow thepopulation model to estimate escapement and predict equilibrium conditions. However, theinfluence of this parameter indicates the primary importance of smolt-to-returning-adult survivalin the Chinook salmon life cycle. The model is also sensitive to available habitat (carryingcapacity) for juveniles, and the survival of age 1+ juveniles to smolts.Table 3-11. Summary of Chinook salmon model sensitivity analysis under current conditions atthe Carmen-Smith Spawning Channel. Adult population estimate is based only on smoltsproduced directly from spawning channel.Adult population estimate based on varying input valueModel parameter 50%decrease25%decreaseCurrentvalue33%increase100%increaseJuvenile capacity (available habitatand density)2 3 5 6 9Age 1+ juvenile to smolt survival 2 3 5 6 6 aMarine survival of smolts to adult 2 3 5 6 9a33% and 100% increase in value results in a survival input of greater than 100%, so no increase in population isestimated.3.7.2 Management implicationsThe Carmen-Smith Spawning Channel is currently producing less than 100 smolts directly fromthe spawning channel. However, the hundreds of thousands of fry produced are estimated toaccount for over 2,500 smolts in the McKenzie River (assuming no habitat limitations in themainstem). Any improvements to rearing conditions in the mainstem McKenzie River thatincreased survival for fry and smolts (e.g., off-channel habitat, improvements to side channels, reconnectionof floodplains) would greatly increase smolt production from the river. For example,increasing survival for migrating fry by 2% increases smolt production to over 8,000 smolts,because most of the fry produced in the spawning channel rear in the mainstem.The current production is based on a gravel augmentation that occurred during July 2005.Superimposition was limited to only a few incidences in Fall 2005, after the gravel augmentation.Presumably, habitat conditions will decline over time, and the amount, and quality, of spawninghabitat will be reduced. Under current conditions the spawning channel could accommodate28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board44

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Reportadditional Chinook salmon spawning based on estimated available habitat, therefore, additionalgravel augmentations would not increase production at this time. However, habitat for fry andjuveniles do limit rearing for early life-stages within the spawning channel. If production fromthe spawning channel is modeled assuming that half of the total area were converted to suitablefry and juvenile habitat (e.g., large woody debris enhancements, off channel habitat), smoltproduction is estimated to triple, even if spawning habitat is reduced by half. As described above,these moderate increases may be dwarfed by the rearing potential of the mainstem McKenzieRiver, and may not be nearly as significant as the potential increases from improvements tohabitat conditions in the mainstem river.3.7.3 Passage at Trail Bridge DamIf fish passage facilities for Chinook salmon at Trail Bridge Dam were constructed, theproportion of fish that would use the Carmen-Smith Spawning Channel, compared with thosemigrating upstream into Trail Bridge Reservoir, is unknown. If escapement increased andChinook salmon spawned in large numbers both upstream of Trail Bridge Dam and in thespawning channel, the net production would be similar to current conditions (with hatcheryreleases of adult Chinook salmon in Trail Bridge Reservoir), assuming all other conditionsremained the same (i.e., no instream flow or habitat enhancements).3.8 Summary3.8.1 Effects of management scenarios on population levelsBased on quantitative modeling efforts, the estimated production of bull trout and spring Chinooksalmon under current conditions and various management scenarios is summarized below (Table3-12). Modeling efforts did not evaluate the cumulative effects of enacting multiple scenariosconcurrently, though such considerations will be addressed in the Draft License Application, dueto FERC in May 2006. In addition, it is not recommended to rely solely on the model predictionspresented here, but instead carefully consider these results in the context of other data andinformation.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board45

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable 3-12. Summary of bull trout and Chinook salmon production in the Study Area undercurrent conditions and various management scenarios.Management ScenarioEstimated production(percent increase from current conditions in parenthesis)Chinook salmon smoltsJuvenile bulltroutSubadult/adultbull troutUpstream ofTrail BridgeDamSpawningchannelCurrent conditions 470 110 1,250 2,700Increased instream flowsCarmen Bypass Reach 1 470 (0%) 110 (0%) 1,450 (15%) NMSmith Bypass Reach 1 470 (0%) 110 (0%) 1,620 a (30%) NMSmith Bypass Reach 2 1,500 (220%) 110 (0%) 1,260 (1%) NMLarge woody debris additions 3Carmen Bypass Reach 850 (80%) 110 (0%) 1,570 (25%) NMSweetwater Creek 590 (25%) 110 (0%) NA NMSmith Bypass Reach NM NM 1,430 (15%) NMSpawning gravel augmentationCarmen Bypass Reach 470 (0%) 110 (0%) 2,000 b (65%) NMSweetwater Creek 470 (0%) 110 (0%) NA NMSmith Bypass Reach 470 (0%) 110 (0%) 1,760 c (40%) NMHabitat enhancements in TrailBridge Reservoir to increase fish 470 (0%) 640 (480%) NM NMdensityReduced hatchery trout planting inTrail Bridge Reservoir480 d (2%) 110 (0%) d 5,500 e (340%) NMFish passage at Smith Dam 470 (0%) 218 (98%) 1,450 (15%) NMDecrease in entrainment mortalityto 1% at Trail Bridge Dam 4 NM NM 1,550 (24%) NMFish passage facilities at TrailBridge Dam, assuming habitat 470 (0%) 800 (630%) 1,250 (0%) f NMdownstream is not limitingFish passage facilities at TrailBridge Dam, assuming habitat 470 (0%) 110 (0%) 1,250 (0%) f NMdownstream is limitingHabitat improvements resulting in2% reduction in fry mortality in the NM NM NM 8,000 (196%)mainstem McKenzie RiverHabitat enhancements in Carmen-Smith Spawning ChannelNM NM NM 2,900 (7%)NM not modeled1 Assumes flows increased to maximize habitat at all life-stages, and redd size increases with increasing habitatavailability.2 Assumes flows increased to provide suitable flows for bull trout during summer.3 Based on 2005 large woody debris enhancements in Carmen Bypass Reach.4 Currently assumed to be 20% in model. Reduction to 1% assumed to occur with NMFS criteria screens, or by guidingfish to an alternative downstream passage route.a Assumes 120 cfs for spawning, and that redd size increases with increasing habitat availability.b Assumes 100 m 2 of gravel, and 20% increase in survival from eggs-to-emergent fry.c Assumes 100 m 2 of gravel, and redd size increases with increasing habitat availability.d Assumes that predation on early life-stages decreases from fewer hatchery fish, or a later stocking date. Potentialincreases in food availability for early life-stages, or potential decreases in food availability for adults were notconsidered.e Assumes mortality in Trail Bridge Reservoir decreases by 30%.f Current model assumes Chinook salmon have passage at Trail Bridge Dam.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board46

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report3.8.1.1 Interactions between bull trout and spring Chinook salmonInteractions between bull trout and Chinook salmon may be important considerations inmanagement decisions. Fish passage facilities at Trail Bridge Dam provide an opportunity to reintroducea natural run of adult spring Chinook salmon upstream of Trail Bridge Dam, where bulltrout have remained since the dam was built. Modeling and observations of hatchery-releasedadult spring Chinook salmon (see Stillwater Sciences 2006a) were used to evaluate three potentialeffects of the interactions between these two species, if fish passage facilities allowed them tooccupy the same space: (1) competition for habitat, (2) competition for food, and (3) bull troutpredation of Chinook salmon.Based on superimposition modeling and observations during spawning surveys, competition forspawning habitat would not have a deleterious effect on either species. Based on directobservation snorkel surveys, native trout are able to out-compete Chinook salmon fry for rearinghabitat in the Carmen Bypass Reach and Smith Bypass Reach. However, Chinook salmon fryand juveniles are able to use the abundant rearing habitat in Trail Bridge Reservoir. Because fryand juvenile stages of bull trout and Chinook salmon use different habitats for rearing, they likelyrequire different food resources, and so they avoid detrimental effects associated withcompetition for food resources. Although no diet analysis was conducted in the Study Area, bulltrout presumably prey on Chinook salmon fry and juveniles produced upstream of Trail BridgeDam. Bull trout bioenergetics could be affected by changes in how the juvenile Chinook salmonuse the reservoir, if passage facilities were provided. Mortality of fry and juveniles currentlylimits the Chinook salmon population (in addition to spawning habitat limitations), though theeffect of bull trout predation relative to predation by hatchery fish is unknown. How mortalityrates observed for Chinook salmon in Trail Bridge Reservoir compare with the mortality rates inthe McKenzie River downstream of Trail Bridge Dam is also unknown.3.8.2 Key factors to protect populationsUnder current conditions and assumptions, the carrying capacity for adult bull trout in TrailBridge Reservoir is limiting the population. Therefore, declines in the population would likelyoccur if survival conditions for adult bull trout declined. For example, increased angling pressureor poaching, or decreases in habitat complexity or food availability in Trail Bridge Reservoir,could increase mortality or emigration. The Carmen Bypass Reach is currently the primaryrearing grounds for juvenile bull trout. Although a decline in the adult population would notnecessarily follow a disturbance in the Carmen Bypass Reach (i.e., production could still occur inSweetwater Creek), it could threaten the long-term stability of the population (population geneticissues are discussed in the Aquatic Habitat Connectivity report). Based on conceptual andquantitative modeling, key factors to protect the bull trout population in the Study Area include:• Existing rearing habitat in the Carmen Bypass Reach,• Subadult/adult survival from angling pressure,• Subadult/adult habitat in Trail Bridge Reservoir, and• Food availability (e.g., Chinook salmon) in Trail Bridge Reservoir.The Project currently blocks Chinook salmon access to historic habitat upstream of Trail BridgeDam. However, if Chinook salmon were to have access to the habitat upstream of Trail BridgeDam, declines in the potential production of the population would likely occur: (1) if spawninghabitat in Carmen Bypass Reach were disturbed (e.g., increased fine sediment in spawninggravel), and/or (2) if mortality were to increase in Trail Bridge Reservoir (e.g., increased stockingof hatchery fish, or increased abundance of adult bull trout). Similarly, disturbances to the28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board47

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportCarmen-Smith Spawning Channel, such as reduced access or use of the spawning channel, orfurther declines in habitat complexity in the mainstem McKenzie River downstream of TrailBridge Dam, could cause declines in the population. Based on conceptual and quantitativemodeling, key factors to protect the Chinook salmon population in the Study Area include:• Spawning habitat in the Carmen Bypass Reach and Carmen-Smith Spawning Channel,• Fry and juvenile survival in Trail Bridge Reservoir, and• Survival during downstream passage at Trail Bridge Dam.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board48

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report4 LITERATURE CITEDAquatic Biology Associates, Inc. 1999. Benthic invertebrate biomonitoring for the McKenzieRiver Watershed Council, Oregon, September-October 1999. Prepared for Willamette NationalForest, Blue River and McKenzie River Ranger Districts, Blue River, Oregon by Aquatic BiologyAssociates, Inc., Corvallis, Oregon.Baxter, J. S. 1995. Chowade River bull trout studies 1995: habitat and population assessment.Prepared for British Columbia Ministry of Environment, Lands and Parks, Fisheries Branch, FortSt. John, British Columbia.Baxter, J. S., and J. D. McPhail. 1996. Bull trout spawning and rearing habitat requirements:summary of the literature. Fisheries Technical Circular No. 98. Fisheries Branch, BritishColumbia Ministry of Environment, Lands, and Parks, Vancouver.Beauchamp, D. A., and J. J. Van Tassell. 2001. Modeling seasonal trophic interactions ofadfluvial bull trout in Lake Billy Chinook, Oregon. Transactions of the American FisheriesSociety 130: 204-216.Ben-James, B. 2001. The feeding ecology of juvenile bull trout, Salvelinus confluentus, in aneastern Cascade stream. Pages 59 in M. K. Brewin, A. J. Paul and M. Monita, editor. Bull trout IIconference proceedings. Trout Unlimited Canada, Calgary, Alberta.Beverton, R. J. H., and S. J. Holt. 1957. On the dynamics of exploited fish populations. MinistryAgirculture, Fisheries and Food, Fisheries Investigation Series 2, No. 19. London, England.Bjornn, T. C. 1978. Survival, production, and yield of trout and Chinook salmon in the LemhiRiver, Idaho. Bulletin No. 27. Prepared by Idaho Cooperative Fishery Research Unit, College ofForestry, Wildlife and Range Sciences, University of Idaho, Moscow for Idaho Department ofFish and Game.Bjornn, T. C., and D. W. Reiser. 1991. Habitat requirements of salmonids in streams. Pages 83-138 in W. R. Meehan, editor. Influences of forest and rangeland management on salmonid fishesand their habitats. Special Publication No. 19. American Fisheries Society, Bethesda, Maryland.Boag, T. D. 1987. Food habits of bull char, Salvelinus confluentus, and rainbow trout, Salmogairdneri, coexisting in a foothills stream in northern Alberta. Canadian Field-Naturalist 101: 56-62.Boag, T. D., and P. J. Hvenegaard. 1997. Spawning movements and habitat selection of bull troutin a small Alberta foothills stream. Pages 317-323 in W. C. Mackay, M. K. Brewin and M.Monita, editor. Friends of the bull trout conference proceedings. Bull Trout Task Force (Alberta),Trout Unlimited Canada, Calgary, Alberta.Buchanan, D. V., and S. V. Gregory. 1997. Development of water temperature standards toprotect and restore habitat for bull trout and other cold water species in Oregon. Pages 119-126 inW. C. Mackay, M. K. Brewin and M. Monita, editor. Friends of the Bull Trout conferenceproceedings. Bull Trout Task Force (Alberta), and Trout Unlimited Canada, Calgary.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board49

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportBuchanan, D. V., M. E. Hanson, and R. M. Hooton. 1997. Status of Oregon's bull trout:distribution, life history, limiting factors, management considerations, and status. OregonDepartment of Fish and Wildlife, Portland.Budy, P., R. Al-Chokhachy, and G. P. Thiede. 2003. Bull trout population assessment and lifehistorycharacteristics in association with habitat quality and land use in the Walla Walla Riverbasin: a template for recovery planning. Annual progress report for 2002. U. S. GeologicalSurvey, Utah Cooperative Fish and Wildlife Research Unit, Department of Aquatic, Watershed,and Earth Resources, Utah State University, Logan.Burner, C. J. 1951. Characteristics of spawning nests of Columbia River salmon. U. S. Fish andWildlife Service Fishery Bulletin 52: 97-110.Cameron, W. A., and G. Paquette. 1991. Fisheries evaluation of Sweetwater Creek, July 1991.USDA Forest Service, Willamette National Forest, Blue River Ranger District, Blue River,Oregon.Chilcote, M. W., S. A. Leider, and J. J. Loch. 1984. Kalamath River salmonid studies. Report No.84-5. Washington State Game Department, Fisheries Management Division, Olympia.Cope, R. S. 2003. Wigwam River juvenile bull trout and fish habitat monitoring program: 2002data report. Technical Report 2002, BPA Report No. DOE/BP-00005672-5. Prepared byWestslope Fisheries, Cranbrook, British Columbia for B. C. Ministry of Environment, Lands andParks, Fisheries Branch, Cranbrook, British Columbia.Cope, R. S. 2004. Middlefork White River and Blackfoot Creek juvenile bull trout and fishhabitat monitoring program: monitor and protect Wigwam River bull trout for KoocamusaReservoir. 2003 Technical Report, Project No. 200000400, BPA Report DOE/BP-00005672-9.Prepared for Bonneville Power Administration, Portland, Oregon.Cope, R. S., and K. J. Morris. 2001. Wigwam River juvenile bull trout and fish habitatmonitoring program: 2000 data report. Prepared by Westslope Fisheries, Cranbrook, BritishColumbia for B. C. Ministry of Environment, Lands and Parks, Fisheries Branch, Cranbrook,British Columbia.Cope, R. S., K. J. Morris, and J. E. Bisset. 2002. Wigwam River juvenile bull trout and fishhabitat monitoring program: 2001 data report. Annual Report 2001, BPA Report No. DOE/BP-00005672-1. Prepared by Westslope Fisheries, Cranbrook, British Columbia for B. C. Ministry ofEnvironment, Lands and Parks, Fisheries Branch, Cranbrook, British Columbia.Cramer, S. P., C. F. Willis, D. Cramer, M. Smith, T. Downey, and R. Montagne. 1996. Status ofWillamette River spring Chinook salmon in regards to the Federal Endangered Species Act. Part2: Determine the extent and causes of trends in abundance for each ESU and Assess the risks thatthreaten persistence of each ESU. Special Report. Submitted to National Marine Fisheries Serviceon behalf of Portland General Electric Company and Eugene Water and Electric Board. S. P.Cramer and Associates, Inc., Gresham, Oregon.Dambacher, J. M., and K. K. Jones. 1997. Stream habitat of juvenile bull trout populations inOregon and benchmarks for habitat quality. Pages 353-360 in W. C. Mackay, M. K. Brewin andM. Monita, editor. Friends of the bull trout conference proceedings. Bull Trout Task Force(Alberta), Trout Unlimited Canada, Calgary, Alberta.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board50

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportDeVries, P. 1997. Riverine salmonid egg burial depths: review of published data and implicationsfor scour studies. Canadian Journal of Fisheries and Aquatic Sciences 54: 1685-1698.Donald, D. B., and D. J. Alger. 1993. Geographic distribution, species displacement, and nicheoverlap for lake trout and bull trout in mountain lakes. Canadian Journal of Zoology 71: 238-247.Downey, T. W., and T. Murtagh. 2001. McKenzie River spring Chinook salmon aerial spawningground surveys. Electronic data submission to StreamNet library, Oregon Department of Fish andWildlife. Eugene Water & Electric Board, Eugene, Oregon.Downs, C. C., D. Horan, E. Morgan-Harris, and R. Jakubowski. 2005. Spawning demographicsand juvenile dispersal of an adfluvial bull trout population in Trestle Creek, Idaho. Prepared byIdaho Department of Fish and Game, Clark Fork, Idaho, U. S. Forest Service, Rocky MountainResearch Station, Boise, Idaho, and Avista Corporation, Natural Resource Office, Noxon,Montana.EA Engineering (EA Engineering, Science, and Technology). 1991. Radio-tracking studies ofadult spring Chinook salmon migration behavior in the McKenzie River, Oregon. Prepared by EAEngineering, Lafayette, California for Eugene Water & Electric Board, Eugene, Oregon.Elle, S., and R. Thurow. 1994. Rapid River bull trout movement and mortality studies. JobPerformance Report, Project F-73-R-16. Idaho Department of Fish and Game, Nampa, Idaho.Elliott, J. M., and M. A. Hurley. 1998. Predicting fluctuations in the size of newly emerged seatroutfry in a Lake District stream. Journal of Fish Biology 53:EWEB (Eugene Water & Electric Board). 2002. Biological assessment for the Eugene Water &Electric Board Carmen-Smith Hydroelectric Project. Draft report. Prepared for Federal EnergyRegulatory Commission, Washington, D. C.EWEB (Eugene Water & Electric Board). 2003. Initial consultation package for relicensing theCarmen-Smith Hydroelectric Project (FERC No. 2242). Final report. Prepared by StillwaterSciences, Arcata, California for EWEB, Eugene, Oregon.Firman, J., R. Schroeder, R. Lindsay, K. Kenaston, and M. Horgansen. 2004. Work completed forcompliance with the biological opinion for hatchery programs in the Willamette Basin, USACEfunding: 2003. Task Order: NWP-OP-FH-02-01.Flatter, B. J. 2000. Life history and population status of migratory bull trout in ArrowrockReservoir, Idaho. Master's thesis. Boise State University, Boise, Idaho.Fraley, J. J., and B. B. Shepard. 1989. Life history, ecology and population status of migratorybull trout (Salvelinus confluentus) in the Flathead Lake and River system, Montana. NorthwestScience 63: 133-143.Goetz, F. 1989. Biology of the bull trout, Salvelinus confluentus, a literature review. USDAForest Service, Willamette National Forest, Eugene, Oregon.Goetz, F. 1994. Distribution and juvenile ecology of bull trout (Salvelinus confluentus) in theCascade Mountains. Master's thesis. Oregon State University, Corvallis.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board51

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportGowan, C., and K. D. Fausch. 1996. Long-term demographic responses of trout populations tohabitat manipulation in six Colorado streams. Ecological Applications 6: 931-946.Grant, J. W. A., and D. L. Kramer. 1990. Territory size as a predictor of the upper limit topopulation density of juvenile salmonids in streams. Canadian Journal of Fisheries and AquaticSciences 47: 1724-1737.Grant, J. W. A., S. O. Steingrimsson, E. R. Keeley, and R. A. Cunjak. 1998. Implications ofterritory size for the measurement and prediction of salmonid abundance in streams. CanadianJournal of Fisheries and Aquatic Sciences 55 (Supplement 1): 181-190.Grimes, J. T., R. B. Lindsay, K. R. Kenaston, K. Homolka, and R. K. Schroeder. 1996.Willamette spring Chinook salmon. Annual Progress Report, Project No. F-163-R-00. OregonDepartment of Fish and Wildlife, Portland, Oregon.Gunckel, S. L., A. R. Hemmingsen, and J. L. Li. 2002. Effect of bull trout and brook troutinteractions on foraging habitat, feeding behavior, and growth. Transactions of the AmericanFisheries Society 131: 1119-1130.Haas, G. R., and J. D. McPhail. 2001. The post-Wisconsinan glacial biogeography of bull trout(Salvelinus confluentus): a multivariate morphometric approach for conservation biology andmanagement. Canadian Journal of Fisheries and Aquatic Sciences 58: 2189-2203.Hagen, J., and J. S. Baxter. 1992. Bull trout populations of the north Thompson River basin,British Columbia: initial assessment of a biological wilderness. Prepared for British ColumbiaMinistry of Enviroment, Lands, and Parks, Fisheries Branch, Kamloops, British Columbia.Hagey, D. 1991. 1990 salmon run summary for the Carmen Smith Spawning Channel. Letter toG. Kunkel.Hagey, D. W. 1968. The operation and evaluation of the Carmen-Smith spawning channel, 1960-67. Summary report. Oregon Fish Commission, Portland.Hardin-Davis, Harza Northwest, and Clearwater BioStudies,. 1991. A report on the developmentof habitat suitability criteria for salmonids of the McKenzie River. Prepared by Hardin-Davis,Inc., Harza Northwest, Inc., and Clearwater BioStudies, Inc. for Eugene Water & Electric Board,Eugene, Oregon.Hayes, J. W. 1987. Competition for spawning space between brown (Salmo trutta) and rainbowtrout (S. gairdneri) in a lake inlet tributary, New Zealand. Canadian Journal of Fisheries andAquatic Sciences 44: 40-47.Healey, M. C. 1991. Life history of Chinook salmon (Oncorhynchus tshawytscha). Pages 311-393 in C. Groot and L. Margolis, editor. Pacific salmon life histories. University of BritishColumbia Press, Vancouver, British Columbia.Herman, S. J. 1997. The unique bull trout spawning population of Pinto Lake, Alberta. Pages217-226 in W. C. Mackay, M. K. Brewin and M. Monita, editors. Friends of the bull troutconference proceedings. Bull Trout Task Force (Alberta), Trout Unlimited Canada, Calgary,Alberta28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board52

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportHomolka, K., and T. W. Downey. 1995. Assessment of thermal effects on salmon spawning andfry emergence, upper McKenzie River, 1992. Information Report 95-4. Oregon Department ofFish and Wildlife, Fish Research and Development Section, Corvallis.Howell, P., J. Hutchison, and R. Hooton. 1988. McKenzie subbasin fish management plan.Oregon Department of Fish and Wildlife, Portland.Hutchison, J. M., and R. M. Hooton. 1990. McKenzie River creel survey, 1983. InformationReports No. 90-1. Oregon Department of Fish and Wildlife, Fish Division, Portland, Oregon.James, P. W., and H. M. Sexauer. 1997. Spawning behaviour, spawning habitat and alternativemating strategies in an adfluvial population of bull trout. Pages 325-329 in W. C. Mackay, M. K.Brewin and M. Monita, editor. Friends of the bull trout conference proceedings. Bull Trout TaskForce (Alberta), Trout Unlimited Canada, Calgary, Alberta.LCOG (Lane Council of Governments). 1996. Technical report for water quality and fish andwildlife habitat. LCOG, McKenzie Watershed Council, Eugene, Oregon.Levings, C. D., and R. B. Lauzier. 1991. Extensive use of the Fraser River basin as winter habitatby juvenile Chinook salmon (Oncorhynchus tshawytscha). Canadian Journal of Zoology 69:1759-1767.Ligon, F. K., W. E. Dietrich, and W. J. Trush. 1995. Downstream ecological effects of dams: ageomorphic perspective. BioScience 45: 183-192.Lindsay, R. B., K. R. Kenaston, R. K. Schroeder, J. T. Grimes, M. G. Wade, K. Homolka, and L.Borgerson. 1997. Spring Chinook salmon in the Willamette and Sandy rivers. Annual ProgressReport, Project No. F-163-R-01. Oregon Department of Fish and Wildlife, Portland, Oregon.Mattson, C. 1948. Spawning ground studies of Willamette River spring Chinook salmon. OregonFish Commission Research Briefs 1: 21-32.McCuddin, M. E. 1977. Survival of salmon and trout embryos and fry in gravel-sand mixtures.Master's thesis. University of Idaho, Moscow.McElhany, P., T. Backman, C. Busack, S. Heppell, S. Kolmes, A. Maule, J. Myers, D. Rawding,A. Steel, C. Steward, and T. Whitesel. 2003. Interim report on viability criteria for Willametteand lower Columbia basin Pacific salmonids. Prepared by Willamette/Lower Columbia TechnicalRecovery Team, NOAA Fisheries, Northwest Fisheries Science Center, Portland, Oregon.McNeil, W. J. 1964. Redd superimposition and egg capacity of pink salmon spawning beds.Journal of the Fisheries Research Board of Canada 21: 1385-1396.Morita, K., and A. Yokota. 2002. Population viability of stream-resident salmonids after habitatfragmentation: a case study with white-spotted charr (Salvelinus leucomaenis) by an individualbased model. Ecological Modelling 155: 85-94.Moussalli, E. and R. Hilborn. 1986. Optimal stock size and harvest rate in multistage life historymodels. Canadian Journal of Fisheries and Aquatic Sciences. 43: 135-141.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board53

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportMuhlfeld, C. C., S. Glutting, R. Hunt, D. Daniels, and B. Marotz. 2003. Winter diel habitat useand movement by subadult bull trout in the upper Flathead River, Montana. North AmericanJournal of Fisheries Management 23: 163-171.Myers, J., C. Busack, D. Rawding, and A. Marshall. 2003. Historical population structure ofWillamette and Lower Columbia river basin Pacific salmonids. Prepared by National MarineFisheries Service, Northwest Fisheries Science Center, Seattle; Washington Department of Fishand Wildlife, Olympia and Vancouver, Washington.Nickelson, T. E., and P. W. Lawson. 1998. Population viability of coho salmon, Oncorhynchuskisutch, in Oregon coastal basins: application of a habitat-based life cycle model. CanadianJournal of Fisheries and Aquatic Sciences 55: 2383-2392.NMFS (National Marine Fisheries Service). 2005a. Endangered and threatened species; finallisting determinations for 16 ESUs of West Coast salmon, and final 4(d) protective regulations forthreatened salmonid ESUs. Federal Register 70: 37160-37204.NMFS (National Marine Fisheries Service). 2005b. Endangered and threatened species;designation of critical habitat for 12 Evolutionarily Significant Units of west coast salmon andsteelhead in Washington, Oregon, and Idaho. Federal Register 70: 52630-52858.NMFS and USFWS (National Marine Fisheries Service and U. S. Fish and Wildlife Service).2000. Biological opinion on effects of Cougar Reservoir water temperature control project onupper Willamette River Chinook salmon, its critical habitat, bull trout, northern spotted owl, andits critical habitat. Endangered Species Act - Section 7 Consultation. Prepared for U. S. ArmyCorps of Engineers by NMFS, Northwest Region and USFWS, Pacific Region.NOAA Fisheries. 2003. Biological opinion and Magnuson-Stevens Fishery Conservation andManagement Act consultation on the effects of EWEB's Carmen-Smith Part 12 submittal toFERC for Trail Bridge Dam emergency spillway expansion, and continued operation of theCarmen-Smith Hydroelectric Project in the McKenzie Subbasin, Oregon on Upper WillametteRiver Chinook salmon. Prepared for Federal Energy Regulatory Commission, Washington, D. C.NOAA Fisheries. 2004. Biological opinion and Magnuson-Stevens Fishery Conservation andManagement Act consultation: Operation of the Cowlitz River Hydroelectric Project (FERC No.2016) through 2038, Cowlitz River, HUC 17080005, Lewis County, Washington. EndangeredSpecies Act Section 7(a)(2) consultation. NOAA Fisheries, Northwest Region, HydropowerDivision, Seattle, Washington.ODFW (Oregon Department of Fish and Wildlife). 1990. McKenzie River, Willamette Riversubbasin: salmon and steelhead production plan. Columbia Basin System Planning. ODFW,Portland.ODFW (Oregon Department of Fish and Game). 1992a. Trap net results from Trail BridgeReservoir for 15 July and 18 September 1992 (“Trail Bridge Reservoir—1992—Trap net on eastshore on point 400 yards from dam”). Unpublished data.ODFW (Oregon Department of Fish and Game). 1999a. Trap net results from Trail BridgeReservoir for 1–2 April and 1–2 September 1999. Unpublished data.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board54

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportODFW (Oregon Department of Fish and Wildlife). 2001a. Cougar Dam Temperature ControlProject: bull trout monitoring. Quarterly reports for the following periods January 1 throughMarch 31, April 1 through June 30, July 1 through September 30, and October 1 throughDecember 31. ODFW, Portland, Oregon.ODFW (Oregon Department of Fish and Wildlife). 2001b. Review of T & E, sensitive, and stocksof concern. Unpublished report. ODFW, South Willamette Watershed District, Springfield,Oregon.ODFW (Oregon Department of Fish and Wildlife). 2001c. 2001 Willamette spring Chinook:Willamette River sport fishing catch and Willamette Falls fish passage counts. Unpublished dataODFW (Oregon Department of Fish and Wildlife). 2001d. Fisheries Management and EvaluationPlan: Upper Willamette River spring Chinook in freshwater fisheries of the Willamette Basin andLower Columbia River mainstem. ODFW, Portland.ODFW (Oregon Department of Fish and Wildlife). 2002a. Cougar Dam Temperature ControlProject: bull trout monitoring. Quarterly reports for the following periods January 1 throughMarch 31, April 1 through June 30, July 1 through September 30, and October 1 throughDecember 31. ODFW, Portland, Oregon.ODFW (Oregon Department of Fish and Wildlife). 2002b. 2002 Willamette spring Chinook:Willamette River sport fishing catch and Willamette Falls fish passage counts. Unpublished data.ODFW (Oregon Department of Fish and Wildlife). 2002c. Stock status report for McKenzieRiver spring Chinook salmon. ODFW, South Willamette District, Springfield, Oregon.http://www.dfw.state.or.us/springfield/McKChs.html.ODFW (Oregon Department of Fish and Wildlife). 2003a. Stock status report: stock status of theMcKenzie bull trout. ODFW, South Willamette District, Springfield, Oregon.ODFW (Oregon Department of Fish and Wildlife). 2003b. Cougar Dam Temperature ControlProject: bull trout monitoring. Quarterly reports for the following periods January 1 throughMarch 31, April 1 through June 30, July 1 through September 30, and October 1 throughDecember 31. ODFW, Portland, Oregon.ODFW (Oregon Department of Fish and Wildlife). 2004a. Cougar Dam Temperature ControlProject: bull trout monitoring. Quarterly reports for the following periods January 1 throughMarch 31, April 1 through June 30, and July 1 through September 30. ODFW, Portland, Oregon.ODFW (Oregon Department of Fish and Wildlife). 2004b. Summary of pit-tag recoveries in 2003and 2004 from antennae at Sweetwater Creek, Anderson Creek, and Olallie Creek. Fish weretagged at either Trail Bridge Reservoir or mainstem upper McKenzie River downstream of TrailBridge Dam. ODFW, Springfield. Unpublished data.ODFW (Oregon Department of Fish and Game). 2004c. Summary of Trail Bridge Reservoir Trapnet sampling, 15–16 November 2004. Unpublished data.ODFW (Oregon Department of Fish and Wildlife). 2004d. Fisheries management and evaluationfor 2003 Willamette River spring Chinook. ODFW, Roseburg.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board55

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportODFW (Oregon Department of Fish and Wildlife). 2004e. 2004 Willamette spring Chinook:Willamette River sport fishing catch and Willamette Falls fish passage counts. Unpublished data.ODFW and Stillwater Sciences (Oregon Department of Fish and Wildlife and StillwaterSciences). 2004. Chinook salmon sex status for hatchery fish released into Trail Bridge Reservoirin 2004. Unpublished data.Oosterhout, G. R., C. W. Huntington, T. E. Nickelson, and P. W. Lawson. 2005. Potentialbenefits of a conservation hatchery program for supplementing Oregon coast coho salmon(Oncorhynchus kisutch) populations: a stochastic model investigation. Canadian Journal ofFisheries and Aquatic Sciences 62: 1920-1935.Parkhurst, Z. E., F. G. Bryant, and R. S. Nielson. 1950. Survey of the Columbia River and itstributaries. Part 3. All tributaries entering the Columbia River on the Oregon side, from the mouthup to, but not including the Deschutes River. Special Scientific Report, Fisheries No. 36.USFWS.Paulik, G. J. 1973. Studies of the possible form of the stock-recruitment curve. Rapports etProces-Verbaux des Reunions, Conseil International pour L'Exploration de la Mer 164: 302-315.Piaskowski, R. M., and R. A. Tabor. 2001. Nocturnal habitat use by juvenile Chinook salmon innearshore areas of Southern Lake Washington, a preliminary investigation, 2000. U. S. Fish andWildlife Service, Western Washington Office, Division of Fisheries and Watershed Assessment,Lacey, Washington.Piper, R. G., I. B. McElwain, L. E. Orme, J. P. McCraren, L. G. Fowler, and J. R. Leonard. 1982.Fish hatchery management. U. S. Fish and Wildlife Service.Pratt, K. L. 1985. Pend Oreille trout and char life history study. Idaho Department of Fish andGame, Boise.Rawson, D. S. 1942. A comparsion of some large alpine lakes in western Canada. Ecology 23:143-161.Reiser, D.W., E. Connor, K. Binkley, K. Lynch, and D. Paige. 1997. Evaluation of spawninghabitat used by bull trout in the Cedar watershed, Washington. Pages 331-338 in Friends of theBull Trout Conference Proceedings (Mackay, W.C., M.K. Brewin, and M. Monita, eds.). BullTrout Task Force (Alberta), c/o Trout Unlimited Canada, Calgary, ABRose, C., and C. Rose. 1997. Bull trout (Salvelinus confluentus) population and habitat surveys inthe McKenzie River system. Oregon Department of Fish and Wildlife, Springfield.Schill, D. J., R. Thurow, and P. Kline. 1994. Seasonal movement and spawning mortality offluvial bull trout in Rapid River, Idaho. Job Performance Report, Project F-73-R-15. IdahoDepartment of Fish and Game.Scholz, A. T., H. J. McLellan, D. R. Geist, and R. S. Brown. 2005. Investigations of migratorybull trout (Salvelinus confluentus) in relation to fish passage at Albeni Falls Dam. Contract No.DACW68-02-D-001. Final report. Prepared by Eastern Washington University, Department ofBiology, Fisheries Research Center, Cheney, Washington and Battelle Pacific Northwest28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board56

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportDivision, Richland, Washington for United States Department of the Army Corps of Engineers,Seattle District, Seattle, Washington.Sedell, J. R., B. A. MacIntosh, and P. Minear. 1992. Evaluation of past and present stream habitatconditions for the Army Corps of Engineers McKenzie River temperature control feasibilitystudy. USDA Forest Service, Pacific Northwest Research Station, Corvallis, Oregon.Sharma, R., A. B. Cooper, and R. Hilborn. 2005. A quantitative framework for the analysis ofhabitat and hatchery practices on Pacific salmon. Ecological Modelling 183: 231-250.Shroeder, R. K., K. R. Kenaston, and R. B. Lindsay. 2003. Spring Chinook salmon in theWillamette and Sandy rivers. Annual Progress Report, F-163-R-08. Oregon Department of Fishand Wildlife, Portland, Oregon.Smith, E. M., B. A. Miller, J. D. Rodgers, and M. A. Buckman. 1985. Outplanting anadromoussalmonids: a literature survey. Annual Report, Project No. 85-68. Prepared by OregonDepartment of Fish and Wildlife for Bonneville Power Administration, Portland, Oregon.Smith, M. 1993. A review of the Carmen-Smith spawning channel: historical review and dataanalysis. Eugene Water & Electric Board, Eugene, Oregon.Stelfox, J. D. 1997. Seasonal movements, growth, survival and population status of the adfluvialbull trout population in lower Kananaskis Lake, Alberta. Pages 309-316 in W. C. Mackay, M. K.Brewin and M. Monita, editors. Friends of the bull trout conference proceedings. Bull Trout TaskForce (Alberta), Trout Unlimited Canada, Calgary, Alberta.Stillwater Sciences. 2004a. Population dynamics of bull trout and spring Chinook salmon. Finalstudy plan. Prepared by Stillwater Sciences, Arcata, California for Eugene Water & ElectricBoard, Eugene, Oregon.Stillwater Sciences. 2004b. Carmen Diversion Dam 2003 maintenance spill. TechnicalMemorandum. Prepared by Stillwater Sciences, Arcata, California for Eugene Water & ElectricBoard, Eugene, Oregon.Stillwater Sciences. 2006a. Fish population distribution and abundance in the Carmen-SmithHydroelectric Project, upper McKenzie River basin, Oregon. Final report. Prepared by StillwaterSciences, Arcata, California for Eugene Water & Electric Board, Eugene, Oregon.Stillwater Sciences. 2006b. Aquatic habitats and instream flows in the Carmen-SmithHydroelectric Project, upper McKenzie River basin, Oregon. Final report. Prepared by StillwaterSciences, Arcata, California for Eugene Water & Electric Board, Eugene, Oregon.Stillwater Sciences. 2006c. Fish entrainment in the Carmen-Smith Hydroelectric Project, upperMcKenzie River basin, Oregon. Final report. Prepared by Stillwater Sciences, Arcata, Californiafor Eugene Water & Electric Board, Eugene, Oregon.Stillwater Sciences. 2006d. Water quality in the Carmen-Smith Hydroelectric Project, upperMcKenzie River basin, Oregon. Final report. Prepared by Stillwater Sciences, Arcata, Californiafor Eugene Water & Electric Board, Eugene, Oregon.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board57

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportStillwater Sciences. 2006e. Flow fluctuations and stranding in the Carmen-Smith HydroelectricProject, upper McKenzie River basin, Oregon. Final report. Prepared by Stillwater Sciences,Arcata, California for Eugene Water & Electric Board, Eugene, Oregon.Stillwater Sciences. 2006f. Aquatic protection, mitigation, and enhancement opportunities in theCarmen-Smith Hydroelectric Project, upper McKenzie River basin, Oregon. Final report.Prepared by Stillwater Sciences, Arcata, California for Eugene Water & Electric Board, Eugene,Oregon.Stillwater Sciences. 2006g. Fluvial geomorphic processes and channel morphology in theCarmen-Smith Hydroelectric Project area, upper McKenzie River basin, Oregon. Final report.Prepared by Stillwater Sciences, Arcata, California for Eugene Water & Electric Board, Eugene,Oregon.Stillwater Sciences. 2006h. Hydrologic regimes at the Carmen-Smith Hydroelectric Project,upper McKenzie River basin, Oregon. Final report. Prepared by Stillwater Sciences, Arcata,California for Eugene Water & Electric Board, Eugene, Oregon.Stillwater Sciences. 2005i. Recreation suitability in the Carmen-Smith Hydroelectric Project area,upper McKenzie River basin, Oregon. Final report. Prepared by Stillwater Sciences, Arcata,California for Eugene Water & Electric Board, Eugene, Oregon.Stillwater Sciences. 2006j. Aquatic habitat connectivity in the Carmen-Smith HydroelectricProject area, upper McKenzie River basin, Oregon. Final report. Prepared by Stillwater Sciences,Arcata, California for Eugene Water & Electric Board, Eugene, Oregon.Swanberg, T. R. 1997. Movements of and habitat use by fluvial bull trout in the Blackfoot River,Montana. Transactions of the American Fisheries Society 126: 735-746.Swartzman, G. L., and D. A. Beauchamp. 1990. Simulation of the effect of rainbow troutintroduction in Lake Washington. Transactions of the American Fisheries Society 119: 122-134.Tabor, R. A., M. T. Celedonia, F. Mejia, R. M. Piaskowski, D. L. Low, B. Footen, and L. Park.2004. Predation of juvenile Chinook salmon by predatory fishes in three areas of the LakeWashington Basin. Publications - 5, Food Habits/Predation. U. S. Fish & Wildlife Service-Pacific Region, Fisheries Division. http://www.fws.gov/westwafwo/fisheries/wwfish_pub5.htm.Tagart, J. V. 1976. The survival from egg deposition to emergence of coho salmon in theClearwater River, Jefferson County, Washington. Master's thesis. University of Washington,Seattle.Taylor, G. A. 2000. Monitoring of downstream fish passage at Cougar Dam in the South ForkMcKenzie River, Oregon, 1998-2000. Oregon Department of Fish and Wildlife.Taylor, G. A. 2003. Bull trout (Salvelinus confluentus) population and habitat surveys in theMcKenzie and Middle Fork Willamette basins, 2001. Annual Report 2001 BPA Report DOE/BP-00004093-2. Bonneville Power Administration, Portland, Oregon.Taylor, G. A., and A. Reasoner. 1998. Bull trout (Salvelinus confluentus) populations and habitatsurveys in the McKenzie and Middle Fork Willamette basins, 1998. Oregon Department of Fishand Wildlife, Springfield.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board58

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTaylor, G. A., and A. Reasoner. 2000. Bull trout (Salvelinus confluentus) population and habitatsurveys in the McKenzie and Middle Fork Willamette basins. Annual Report 1999, DOE/BP-00000226-1. Bonneville Power Administration, Portland, Oregon.Taylor, G. A., and J. Ziller. 2000. Bull trout (Salvelinus confluentus) population and habitatsurveys in the McKenzie and Middle Fork Willamette basins, 2000. Annual Report 2000 BPAReport DOE/BP-00004093-1. Bonneville Power Administration, Portland, Oregon.Torgersen, C. E., R. N. Faux, and B. A. McIntosh. 1999. Aerial survey of the upper McKenzieRiver: thermal infrared and color videography. Oregon State University, Corvallis.USDA Forest Service. 1990. Willamette National Forest land and resource management plan.Final environmental impact statement. USDA Forest Service, Northwest Region, Eugene,Oregon.USDA Forest Service. 1991a. Biological stream probes: Kink Creek, Ollalie Creek, Deer Creek,Budworm Creek, and Bunchgrass Creek. USDA Forest Service, Willamette National Forest,McKenzie and Blue River Ranger Districts, Blue River, Oregon. Unpublished data.USDA Forest Service. 1991b. Biological probe: Boone Creek, 7-8 August 1991. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1991c. Biological probe: Penny Creek, 8 August 1991. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1991d. Biological probe: Rider Creek, 8 August 1991. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1991e. Biological probe: Ridge Creek, 13 September 1991. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1991f. Scuba surveys of Trail Bridge Reservoir, 4 May and 17 July 1991.Unpublished data.USDA Forest Service. 1992a. Bull trout redd counts from spawning surveys conducted byODFW and USDA Forest Service, 1989-1992. USDA Forest Service. Unpublished data.USDA Forest Service. 1992b. Biological probe: Boulder Creek, 6 June 1992. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992c. Biological probe: Boulder Creek, 7 June 1992. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board59

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportUSDA Forest Service. 1992d. Biological probe: Elk Creek, 28 July and 4 August 1992. USDAForest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992e. Biological probe: Ikenick Creek, 28 April 1992. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992f. Biological probe: Lost Creek, 19 and 26 May 1992. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992g. Biological probe: Lost Creek, 10 December 1992. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992h. Biological probe: North Fork Olallie Creek, 12 May 1992. USDAForest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992i. Biological probe: Roney Creek, 6 October 1992. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992j. Biological probe: Scott Creek, 21 July 1992. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1992k. Biological probe: South Fork McKenzie River, 18 August 1992.USDA Forest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts,Oregon. Unpublished data.USDA Forest Service. 1992l. Scuba surveys of Trail Bridge Reservoir, 29 May and 6 November1992. Unpublished data.USDA Forest Service. 1992m. Lower Horse Creek side channel, 1992 enhancement monitoring,Blue River/McKenzie Ranger Districts. Unpublished data.USDA Forest Service. 1993a. Upper McKenzie River redd count, 15 and 19 October 1993.Unpublished data.USDA Forest Service. 1993b. Biological probe: Eugene and Horse Creek confluence, 26 August1993. USDA Forest Service, Willamette National Forest, McKenzie and Blue River RangerDistricts, Oregon. Unpublished data.USDA Forest Service. 1993c. Scuba survey of Trail Bridge Reservoir, 18 June 1993.Unpublished data.USDA Forest Service. 1993d. Sweetwater Creek snorkel, project effectiveness monitoring, 14October 1993. Unpublished data.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board60

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportUSDA Forest Service. 1993e. Anderson Creek study section: habitat manipulation monitoringreport. USDA Forest Service, Willamette National Forest, McKenzie Ranger District, McKenzieBridge, Oregon.USDA Forest Service. 1994a. Biological probe: Capurso Creek, 24 February 1994. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1994b. Bull trout probe: Harvey Creek, 7 September 1994. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1994c. Biological probe: McBee Creek, 21 July 1994. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1994d. Biological probe: Roaring River, 21 July 1994. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1994e. Biological probe: Roaring River, 4 August 1994. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1994f. Biological probe: Roaring River- upper section, 4 August 1994.USDA Forest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts,Oregon. Unpublished data.USDA Forest Service. 1994g. Bull trout probe: Separation Creek, 6 September 1994. USDAForest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1994h. Bull trout probe: Separation Creek, 7 September 1994. USDAForest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1994i. Biological probe: South Fork McKenzie River, 10 August 1994.USDA Forest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts,Oregon. Unpublished data.USDA Forest Service. 1994j. Deer Creek side channel, effectiveness monitoring, snorkeled 4 and18 April 1994. Unpublished data.USDA Forest Service. 1995a. McKenzie Ranger District bull trout redd count report: UpperMcKenzie River, Tamolitch to Trail Bridge, 2 November 1995. Unpublished data.USDA Forest Service. 1995b. Anderson Creek bull trout redd count. Unpublished data.USDA Forest Service. 1995c. Olallie redd count, 4 October 1995. Unpublished data.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board61

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportUSDA Forest Service. 1995d. South Fork McKenzie/Roaring River bull trout redd surveys,October 1995. Unpublished data.USDA Forest Service. 1995e. Paradise side channel aquatic ecosystem project, effectivenessmonitoring report, McKenzie Ranger District, 9 February 1995. Unpublished data.USDA Forest Service. 1995f. Sweetwater Creek snorkel, project effectiveness monitoring, bulltrout survival and growth, 24 August 1995. Unpublished data.USDA Forest Service. 1995g. Upper McKenzie watershed analysis. USDA Forest Service,Willamette National Forest, McKenzie Ranger District, McKenzie Bridge, Oregon.USDA Forest Service. 1996. Buck side channel aquatic ecosystem project, effectivenessmonitoring report, McKenzie Ranger District.USDA Forest Service. 1997a. Upper McKenzie final redd count, bull trout and Chinook, October15, 1997. Unpublished data. USDA Forest Service, McKenzie Ranger District, WillametteNational Forest, McKenzie Bridge, Oregon.USDA Forest Service. 1997b. Bull trout redd survey, Sweetwater Creek, 16 October 1997.Unpublished data. USDA Forest Service, McKenzie Ranger District, Willamette National Forest,McKenzie Bridge, Oregon.USDA Forest Service. 1997c. Smith River redd count, October 15 and 23, 1997. Unpublisheddata. USDA Forest Service, McKenzie Ranger District, Willamette National Forest, McKenzieBridge, Oregon.USDA Forest Service. 1997d. Bull trout probe: Kink Creek, 26 June 1997. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1997e. Bull trout probe: upper Seperation Creek, 18 August 1997. USDAForest Service, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1997f. Buck side channel, effectiveness monitoring results, 28 August1997. Unpublished data.USDA Forest Service. 1997g. Sweetwater Creek snorkel, project effectiveness monitoring, bulltrout survival and growth, 31 July 1997. Unpublished data.USDA Forest Service. 1998a. Bull trout redd surveys, Upper McKenzie River (above TrailBridge Dam), September/October 1998. Unpublished data.USDA Forest Service. 1998b. Bull trout redd surveys, Anderson Creek, 21 October 1998.Unpublished data.USDA Forest Service. 1998c. Bull trout redd surveys: Upper South Fork McKenzie River, 8October 1998; Roaring River, 6 and 19 October 1998. Unpublished data.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board62

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportUSDA Forest Service. 1998d. Bull trout redd survey, Sweetwater Creek, September/October1998. Unpublished data.USDA Forest Service. 1998e. Bull trout and enhancement monitoring survey, McKenzie RangerDistrict: Anderson Creek, 22 January 1998. Unpublished data.USDA Forest Service. 1998f. Bull trout surveys: McKenzie River, Mile Post 44 log jam, 6October 1998. USDA Forest Service, Willamette National Forest, McKenzie and Blue RiverRanger Districts, Oregon. Unpublished data.USDA Forest Service. 1998g. Bull trout probe: Lost Creek, 16 September 1998. USDA ForestService, Willamette National Forest, McKenzie and Blue River Ranger Districts, Oregon.Unpublished data.USDA Forest Service. 1999. Bull trout monitoring report, Blue River/McKenzie Ranger Districts,December 1999.USDA Forest Service. 2001a. Table 4-11: Occurrence of bull trout fry or juveniles in streamssurveyed by day or nighttime snorkeling, electrofishing, or foot survey, 1991-2001. Unpublisheddata.USDA Forest Service. 2001b. Sweetwater Creek snorkel, project effectiveness monitoring, 12December 2001. Unpublished data.USDA Forest Service. 2002a. Upper McKenzie bull trout snorkel downstream of Trail BridgeDam, 11 October 2002. Unpublished data.USDA Forest Service. 2003a. RE: Annual report to the U. S. Fish and Wildlife Service asrequired by Section 10 permit TE001822-3. Letter to V. M. Finn, Chief--Endangered Species, U.S. Fish and Wildlife Service, Portland Regional Office, Portland, Oregon from USDA ForestService, Willamette National Forest, Eugene, Oregon.USDA Forest Service. 2003b. Upper McKenzie redd count, bull trout and Chinook, 25 September2003. Unpublished data.USDA Forest Service. 2003c. Sweetwater Creek redd count, 11 November 2003. Unpublisheddata.USDA Forest Service. 2003d. Temperature data from Anderson Creek (1999–2003), Elk Creek(2000–2003), Olallie Creek (1999–2003), Roaring River (1999–2003), South Fork McKenzieRiver (2000–2003), Separation Creek (2001–2002), Sweetwater Creek (1999–2003), mainstemupper McKenzie River upstream of Trail Bridge Dam (1998–2003). Unpublished data.USDA Forest Service. 2003e. Upper McKenzie bull trout snorkel downstream of Trail BridgeDam, 29 July 2003. Unpublished data.USDA Forest Service. 2003f. Temperature data from the mainstem upper McKenzie Riverupstream of Trail Bridge Dam (1998–2003). Unpublished data.USDA Forest Service. 2004a. Table 1: Bull trout redd counts from spawning surveys conductedby ODFW, Stillwater Sciences, and Forest Service, 1989–2004. Includes data for Anderson Creek28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board63

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical Report(above and below culvert), mainstem upper McKenzie River (upstream and downstream of TrailBridge Dam, Olallie Creek (above and below culvert), Sweetwater Creek, and Roaring River(South Fork McKenzie River basin). Unpublished data.USDA Forest Service. 2004b. Olallie Creek Vaki RiverWatcher upstream migrant counts atHighway 126 for years 2003 and 2004. Unpublished data.USDA Forest Service. 2004c. Olallie Creek redd count, 5 October 2004. Unpublished data.USDA Forest Service. 2004d. Anderson Creek migrant trapping results for years 1993–2004,Julian weeks 6–22 [spreadsheet]. Unpublished data.USDA Forest Service. 2004e. Anderson Creek previous year redd count above trap vs. totalestimated fry migration based on migrant trapping results. Unpublished data.USDA Forest Service. 2004f. Maximum, average, and minimum sizes of bull trout fry in 2003(June through mid-August) and 2004 (March through mid-August) in Anderson Creek based onmigrant trapping studies. Unpublished data.USFWS (U. S. Fish and Wildlife Service). 2002. Willamette River Recovery Unit, Oregon.Chapter 5 in Bull trout (Salvelinus confluentus) draft recovery plan. USFWS, Region 1, Portland,Oregon.USFWS (U. S. Fish and Wildlife Service). 2003. Biological/conference opinion on the effects ofEWEB's Carmen-Smith Part 12 submittal to FERC for Trail Bridge spillway expansion, andinterim operation of the Carmen-Smith Hydroelectric Project in the McKenzie Subbasin, Oregonon bull trout, bald eagle, and northern spotted owl. Endangered Species Act - Section 7 (a)(2)Consultation; USFWS Log No. 1-7-03-F-455. Prepared for Federal Energy RegulatoryCommission by USFWS, Oregon Fish and Wildlife Office.USFWS (U. S. Fish and Wildlife Service). 1998. Endangered and threatened wildlife and plants;determination of threatened status for the Klamath River and Columbia River distinct populationsegments of bull trout. Federal Register 63: 31647-31674.USFWS (U. S. Fish and Wildlife Service). 2004a. Endangered and threatened wildlife and plants;designation of critical habitat for the Klamath River and Columbia River populations of bulltrout; final rule. Federal Register 69: 59996-60075.USFWS (U. S. Fish and Wildlife Service). 2004b. Draft recovery plan for the Coastal-PugetSound Distinct Population Segment of bull trout (Salvelinus confluentus). Volume I: Puget SoundManagement Unit. USFWS, Region 1, Portland, Oregon.USGS. 2004. Unpublished stream gage data: McKenzie River at outlet of Clear Lake (No.14158500) (1913–1915 and 1948–2004), McKenzie River below Trail Bridge Dam (No.14158850) (1961–2004), McKenzie River near Vida (No. 14162500) (1925 to present),McKenzie River at McKenzie Bridge (No. 14159000) (1910–1994), and Smith River aboveSmith River Reservoir (No. 14158790Wetherall, J. A. 1971. Estimation of survival rates for Chinook salmon during their downstreammigration in the Green River, Washington. Doctoral dissertation. College of Fisheries, Universityof Washington.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board64

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportWillis, C. F., S. P. Cramer, M. Smith, D. Cramer, T. Downey, and R. Montagne. 1995. Status ofWillamette River spring Chinook salmon in regards to the Federal Endangered Species Act. Part1: Determine which spring Chinook population groupings within the Willamette Basin qualify asEvolutionarily Significant Units (ESUs). Special Report. Submitted to National Marine FisheriesService on behalf of Portland General Electric Company and Eugene Water and Electric Board.S. P. Cramer and Associates, Inc., Gresham, Oregon.Zakel, J. C., and D. W. Reed. 1984. Downstream migration of fish at Leaburg Dam, McKenzieRiver, Oregon: 1980-1983. Information Report No. 84-13. Oregon Department of Fish andWildlife, Research and Development Section, Corvallis and Eugene Water and Electric Board,Eugene, Oregon.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric Board65

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportFiguresCopyright © 2006 Eugene Water & Electric Board - the following Figures to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report

HydrologicRegimesRIVER CHANNEL DYNAMICSSedimentBudgetLarge WoodyDebrisDynamicsAQUATIC HABITAT CONDITIONSWater QualityFluvial GeomorphicProcesses andChannel MorphologyAquatic Habitatsand Instream FlowsAquatic HabitatConnectivityFISHERIESBOTANY AND WILDLIFESOCIAL SCIENCESFish Population Distributionand AbundanceVegetation and WetlandMapping andCharacterizationHistorical andArchaeological ResourcesEntrainmentBotanical Field SurveysExisting Recreational UseFlow Fluctuations andStrandingWildlifeDistributionRecreation SuitabilityPopulation Dynamics ofBull Trout and SpringChinook SalmonWildlife AnalysesWhitewater BoatingFeasibilityFish Passage FeasibilityAesthetic ResourcesAquatic Protection,Mitigation, andEnhancement OpportunitiesLicense ApplicationLand Use and ManagementFigure 1-1. Relationship of the Population Dynamics of Bull Trout and Spring Chinook Salmon study to other Carmen-SmithHydroelectric Project relicensing studies.

Figure 1-2. Study Area and modeled subreaches and reservoirs.

Egg regionDefended regionGravel patchFigure 2-1. Egg region and defended region of a redd, as treated in the redd superimposition model (Escape 5.1).

1 2Figure 2-2. Example of the bull trout population model showing the step from “stock” (1) to “production” (2).

Fluvial and adfluvial life history strategy: large top predatorLarge size, feeds on salmon smolts and larger resident fish –Avoids the need to feed on small invertebratesLong-livedLow recruitmentneeded to maintainpopulationSpawning strategy: moreenergy to growth and survival,less to reproductionMust be able to grow large duringcold climates, e.g. PleistoceneLow adult mortalityMutedspawningcolorsReduced orabsent redddefenseSmall eggsFlexiblespawningfrequencyDelayedmaturationLowfecundity• Maximum growth atlower temperaturesthan other salmonids• Higher growth rates atlower suboptimaltemperatures thanother salmonidsEarlypiscivoryExtensivemigrationfor feedingStalkingpredationSecretivebehaviorOnly competitive incold streamsReducedforagecostsHighcannibalismNightspawningAdult habitatsaturated becauselimited relative tojuvenile recruitmentLimited fry and juvenilerearing habitatTerritorialityensures foodfor growthHigh mortalityOf subadultsHigh mortalityof fry and juvenilesFry and juveniles:benthic orientationand feedingPiscivores:ambushpredatorsSecretivefry andjuvenilesFigure 3-1. Bull trout conceptual model upstream of Trail Bridge Dam, prior to European influence.

Figure 3-2. Conceptual model of bull trout habitat in the McKenzie River basin prior to European influence, 300 to 10,000 years before present.

FISHINGPRESSURELong-livedLow adult mortalityMutedspawningcolorsStalkingpredationNightspawningReduced orabsent redddefenseSecretivebehaviorFluvial and adfluvial life history strategy: large top predatorLarge size, feeds on salmon smolts and larger resident fish –Avoids the need to feed on small invertebratesLow recruitmentneeded to maintainpopulationSmall eggsCHANGES INAMOUNTSAND TYPESOF HABITATSAdult habitatsaturated becauselimited relative tojuvenile recruitmentSpawning strategy: moreenergy to growth and survival,less to reproductionFlexiblespawningfrequencyENTRAINMENTMORTALITYHYBRIDIZATIONLowfecundityDelayedmaturation• Maximum growth atlower temperaturesthan other salmonids• Higher growth rates atlower suboptimaltemperatures thanother salmonidsOnly competitive incold streamsLimited fry and juvenilerearing habitatMust be able to grow large duringcold climates, e.g. PleistoceneTerritorialityensures foodfor growthCHANGESIN FORAGEBASEReducedforagecostsLACK OFPASSAGEExtensivemigrationfor feedingEarlypiscivoryHighcannibalism= impactHigh mortalityOf subadultsHigh mortalityof fry and juvenilesFry and juveniles:benthic orientationand feedingPiscivores:ambushpredatorsSecretivefry andjuvenilesFigure 3-3. Bull trout conceptual model upstream of Trail Bridge Dam, under current conditions.

Figure 3-4. Current bull trout habitat in the McKenzie River basin.

Stream rearing anadromous life history strategy:large adults, large smoltsAdults migrate in springand hold in summerRequire deep-coldpools for holdingEarly spawningand thus earlyemergenceFry rear in upstreamspawning areasFry migratedownstreamLarge riversHigh elevationSpring-fedIf If habitat is is not available,fry don’t contributeto populationSteepergradientCool, suitable summer rearing habitatin upstream spawning areas usuallyeasily saturated by emergent fry• Food• SpaceIf If habitat is is available,fry have growthadvantage over fallrunChinook salmonHigh stream power – coarse bed,small amount of large gravels1+ smoltscommon0+ and 1+smolts commonSpawning habitatlimitingRearing habitatlimitingFigure 3-5. Spring Chinook salmon conceptual model in the McKenzie River, prior to European influence.

Large riversRequire deep-coldpools for holdingCHANGES IN AMOUNTSAND TYPES OFHABITATSHigh elevationSteepergradientHigh stream power – coarse bed,small amount of large gravelsSEDIMENT TRANSPORTDISRUPTEDFISHINGPRESSUREStream rearing anadromous life history strategy:large adults, large smoltsSpring-fedSpawning habitatlimitingAdults migrate in springand hold in summerFry rear in upstreamspawning areasCool, suitable summer rearing habitatin upstream spawning areas usuallyeasily saturated by emergent fry• Food• SpaceCHANGES INAMOUNTS ANDTYPES OF HABITATSRearing habitatlimitingLACK OFPASSAGEEarly spawningand thus earlyemergenceCHANGES INAMOUNTS ANDTYPES OFHABITATSIf If habitat is is not available,fry don’t contributeto population1+ smoltscommonPREDATION BYINTRODUCEDFISH SPECIESENTRAINMENTMORTALITY= impactFry migratedownstreamIf If habitat is is available,fry have growthadvantage over fallrunChinook salmon0+ and 1+smolts commonFigure 3-6. Spring Chinook salmon conceptual model in the McKenzie River under current conditions.

Figure 3-7. Schematic of bull trout population model results. The stock and production of each life-step is shown for one cohort, fromspawning (far left) in either Sweetwater Creek or Carmen Bypass Reach, through each life-stage, to adults in Trail Bridge Reservoir (farright). Carrying capacity for each life-stage is shown by the gray box, and population size for each life-stage is shown in yellow. Bothcarrying capacity and population size are shown in proportion between life-stages; the broken line for eggs and emergent fry indicatesthat these life-stages are not shown in proportion. Mortality rate is shown, and explains the population decline within each life-step.

500450400Baseflow conditions - 160 cfsWithout superimpositionEffective bull trout females3503002502001501005000 50 100 150 200 250 300 350 400 450 500Actual bull trout femalesFigure 3-8. Effects of superimposition on bull trout spawning in Carmen Bypass Reach, based on suitable spawninghabitat mapping at 160 cfs.

Figure 3-9. Schematic of Chinook salmon population model results. The stock and production of each life-step is shown for one cohort,from spawning (far left), through each life-stage, to smolts (far right). Carrying capacity for each life-stage is shown by the gray box, andpopulation size for each life-stage is shown in yellow. Both Carrying capacity and population size are shown in proportion between lifestages;the broken line for eggs and emergent fry indicates that these life stages are not shown in proportion. Mortality rate is shown,and explains the population decline within each life-step.

50454035Effective females atbaseflow conditions -160 cfsAdditional females prevented fromspawning due to redd defense.Effective females3025201510500 5 10 15 20 25 30 35 40 45 50Actual femalesFigure 3-10. Effects of increased escapement on Chinook salmon spawning in Carmen Bypass Reach, based on suitablespawning habitat mapping at 160 cfs.

2520Minimum temperature65Mean temperature60Maximum temperature55Juvenile rearing(4-10 o C)8075757065151560o C1010Spawning(4-10 o C)5550o FLate fry rearing(4-10 o C)455500May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul5/1/046/1/047/1/048/1/049/1/04Eggincubation(1-6 o C)10/1/0411/1/0412/1/041/1/052/1/053/1/054/1/055/1/056/1/05Early fry rearing(4-4.5 o C)7/1/05Aug Sep Oct04 04 04 05 05 05 05 05 05 05 05 05 05 05 05 05 05 058/1/059/1/054035353030Figure 3-11. Optimal temperature for bull trout life stages. Bull trout temperature requirements based on Buchanan and Gregory(1997). Periodicity of bull trout based on Fish Population Distribution and Abundance study (Stillwater Sciences 2005a). Water temperaturedata recorded on Smith River, above Smith Reservoir (Stillwater Sciences 2005d).

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendicesCopyright © 2006 Eugene Water & Electric Board - the following Appendices to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendix AGlossaryCopyright © 2006 Eugene Water & Electric Board - the following Appendix A to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report:Appendix AGlossary

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTermsBeverton-Holt modelCarrying capacity, KCohortDensity-dependentDensity-independentEffective reddsEscape 5.1 sub-modelHockey stick modelDefinitionsStock-production model that the user may select within the populationdynamics models. It is a model commonly used in management of Pacificsalmon, based on Beverton and Holt (1957). This model allows productionto increase until reaching a certain stock level; above this stock level,production remains constant, at the limit defined by the carrying capacity, K.The population dynamics models allow the user to choose between twoversions: Version 1 is the “original” form; Version 2 is a form that allowsproduction to approach carrying capacity at a faster rate (i.e., it allows asteeper curve).A density-dependent term used in stock-production models that representsthe population size limit for a given life-stage. This term represents densitydependentfactors such as spawning gravel area, or abundance of overwinteringrefugia.Members of a life-stage that were spawned in the same year.Factors affecting the population that are dependent on the population size,such as habitat area.Factors affecting the population regardless of population size, such astemperature, disease, or stranding.Completed redds that have survived the effects of superimposition.Model that was used to estimate values to the population dynamics models.The Escape sub-model can provide the number of effective redds anddeposited eggs, given redd characteristics, gravel patch data, and spawntiming data.A stock-production model that is a piece-wise linear function with a slope ofr for the density-independent phase, and with a slope of zero for the densitydependentphase (once reaching carrying capacity) (Barrowman and Myers2000).Rate of population increase, r An input parameter needed in stock-production models. It is a densityindependentterm that represents the net effect of births and/or deaths,resulting from factors such as fecundity, or dependence of egg survival onspawning gravel quality. Depending on the life-stage of interest and thestock-production model selected, the input parameter r represents the fractionof adults spawning, fecundity, or density-independent survival rate.Linear modelA stock-production model that the user may select within the populationdynamics models. This stock-production model assumes a linear relationshipbetween two life-stages, where r is the slope of the line.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardA-1

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportLife-stageTemporal stages (or intervals) of a fish’s life that have distinct anatomical,physiological, and/or functional characteristics that contribute to potentialdifferences in use of the environment.Life-stepProductionStockStock-production modelSuperimposition modelInterval between a production and stock life-stage (i.e., adult to femalespawner)Output from a stock-production model at a particular life-step.Input value required by the stock-production models. It is the first requiredvalue entered into the population dynamics model spreadsheets; for example,stock would be the number of fry, for a fry-to-juvenile step.Relates the number of individuals P in some cohort at one developmentstage, as a function ( F ) of the number of individuals S in that cohort at anearlier development stage:P = F(S). The population dynamics modelsallow the user to choose from the following four stock-production models:(1) Linear (2) Hockey stick, (3) Beverton-Holt 1 (Beverton and Holt 1957),4) Beverton-Holt 2, and (5) Superimposition.A stock-production model that the user may select within the populationdynamics models. The values for this model are based on results from theEscape sub-model, for varying levels of spawning escapement. This modelis used to estimate the number of deposited eggs based on the number offemale spawners.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardA-2

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendix BExisting local information for bull trout population dynamicsmodelTablesTable B-1. Potential bull trout population dynamics model parameters and relevant available informationor information anticipated to be collected in the Relicensing studies. .................................. B-1Copyright © 2006 Eugene Water & Electric Board - the following Appendix B to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report:Appendix BExisting local information for bull trout population dynamicsmodel

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable B-1. Potential bull trout population dynamics model parameters and relevant available information or information anticipated to becollected in the Relicensing studies.Potential modelinputExamples of potentially usefultypes of dataAvailable local information(including information that may result from relicensing studies)Life-stage: Spawning. The goal of this section of the model is to predict the number of eggs that are successfully deposited in the gravel for differentnumbers of spawners, i.e., a spawner-to-egg stock-production curve. To do this we need an estimate of fecundity, and mortality due to redd superimposition.Number ofspawnersKnown number of spawnersThis type of data can be used totest model predictions and allowsassessment of year-to-yearvariability.Types of data:• estimates of spawningescapement [best]• spawning surveys/redd counts[good]Existing local information• Estimate of the number of mature adults from Anderson Creek in 1999, and from RoaringRiver in 1999 (J. Ziller, ODFW, pers. comm., 1999; as cited in NMFS and USFWS 2000)• Potential number of spawning adults above Trail Bridge Dam, in Anderson Creek, and for theCougar Reservoir/Roaring River subpopulation (ODFW 2003a)• USDA Forest Service and ODFW redd counts in Anderson Creek from 1989-2004, OlallieCreek from 1994-2004, Sweetwater Creek from 1994-2004, mainstem McKenzie Riverabove Trail Bridge from 1994-2004, and Roaring River from 1993-2004 (USDA ForestService 2004a, unpublished data)• Spawning survey observations, USDA Forest Service and ODFW, from the Upper McKenzieRiver above Trail Bridge in 1993, 1995, 1997, 1998, and 2003 (USDA Forest Service 1993a,1995a, 1997a, 1998a, and 2003b; unpublished data), and Anderson Creek in 1995 and 1998(USDA Forest Service 1995b and 1998b, unpublished data), Olallie Creek in 1995 (USDAForest Service 1995c, unpublished data), Upper South Fork McKenzie/Roaring River in 1995and 1998 (USDA Forest Service 1995d and 1998c, unpublished data), and Sweetwater Creekin 1997, 1998 and 2003 (USDA Forest Service 1997b, 1998d, and 2003c; unpublished data),and lower Smith River in 1997 (USDA Forest Service 1997c, unpublished data), includescounts from individual surveys and estimated number of adults for Olallie Creek in 1995(USDA Forest Service 1995c, unpublished data)• Vaki RiverWatcher data from 1999-2001 for Anderson Creek and Roaring River (Taylor andReasoner 2000, Taylor and Ziller 2000, and Taylor 2003)• Video footage from Sweetwater Creek in 2002, and Vaki RiverWatcher data from 2002 forAnderson and Ollalie creeks and Roaring River (USDA Forest Service 2003a)• Vaki RiverWatcher data from Olallie Creek in 2003-2004 (USDA Forest Service 2004b,unpublished data)• Vaki RiverWatcher data from South Fork McKenzie and Cougar Reservoir from 2001-2004(ODFW 2001a, 2002b, 2003b, and 2004a; unpublished data)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-1

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of dataFrequency of spawning. What isthe frequency of spawning (e.g.annually, bi-annually?)The frequency of spawning is usedin conjunction with the modelednumber of adult females toestimate number of spawners in agiven year.Types of data:• multi-year PIT-tag or otherindividual ID tag data fromknown spawning areas (foridentified females) [best]• trends in female spawnerabundance over time [ok]• sex ratio of adult populationversus spawners [ok]Temporal distribution ofspawning run. Dates andtemporal pattern of spawning. Isthe temporal distribution normal orskewed?Knowing this information willhelp us determine how manypotential spawners are able tosuccessfully spawn and hasimplications for reddsuperimposition. A short windowof redd construction could meanthere is more likely to be an evendistribution of spawners; a longerAvailable local information(including information that may result from relicensing studies)Data from relicensing studies• Spawning surveysExisting local information• ODFW PIT tag data from Trail Bridge Reservoir, Sweetwater Creek, and Trail Bridgetailrace from 2003-2004 (ODFW 2004b, unpublished data)• ODFW PIT tag data from South Fork McKenzie and Cougar Reservoir from 2001-2004(ODFW 2001a, 2002b, 2003b, and 2004a; unpublished data)• Spawning frequency in Cougar Reservoir/Roaring River subpopulation (M. Wade, ODFW,pers. comm., 3 November, 2004)• Spawning frequency in lower McKenzie River population based on radio tracking data from3 fish (Rose and Rose 1997)• Sex ratios during spawning, Willamette Basin (ODFW 2001b, as cited in USFWS 2002)Local sources needed• ODFW. 2001b. Review of T&E, sensitive, and stocks of concern. ODFW, South WillametteWatershed District, Springfield. [as cited in USFWS 2002]Data from relicensing studies• PIT tag analysisExisting local information• McKenzie River spawning timing (Taylor and Reasoner 1998, Taylor and Reasoner 2000,Taylor 2003)• ODFW PIT tag data from Trail Bridge Reservoir, Sweetwater Creek, and Trail Bridgetailrace from 2003-2004 (ODFW 2004b, unpublished data)• ODFW PIT tag data from South Fork McKenzie and Cougar Reservoir from 2001-2004(ODFW 2001a, 2002b, 2003b, and 2004a; unpublished data)• Dates of beginning, end, and peak of upstream migration, and redd counts; see above forexisting local information re: the known number of spawners, particularly redd count andVaki RiverWatcher dataData from relicensing studies• spawning surveys28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-2

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of datawindow of redd constructionallows for a greater opportunity forredd-superimposition. In addition,we would like to compare thetemporal distribution of Chinooksalmon with bull trout to evaluatethe potential for intra-specific reddsuperimposition.Types of data:• spawning timing curves [best]• spawning surveys/redd counts[good]• dates of beginning, end, andpeak of upstream migration orspawning [ok]The best data for describingtemporal distribution would beactual curves of numbers ofspawning fish over time; lessvaluable, but still useful data couldinclude beginning, peak, and endtimes for the run.Age/size structure of population.This information will be used toestimate the number of maturefemales in the adult population.Types of data:• age/size-specific probabilities ofspawning [best]• data on sizes of spawning adults(preferably at known ages)Available local information(including information that may result from relicensing studies)• Vaki RiverWatcher detections• PIT tag analysisExisting local information• Sizes of spawning adults, ODFW PIT tag data from Trail Bridge Reservoir, SweetwaterCreek, and Trail Bridge tailrace from 2003-2004 (ODFW 2004b, unpublished data)• Sizes of spawning adults, ODFW PIT tag data from South Fork McKenzie and CougarReservoir (ODFW 2001a, 2002b, 2003b, and 2004a; unpublished data)• Estimated sizes of spawning adults, based on Vaki RiverWatcher data, see above for existinglocal information re: the known number of spawners, Vaki RiverWatcher information only• Size of one sexually mature female, based on illegal angling catch in Trail Bridge Reservoirin 1992 (USDA Forest Service 1992a, unpublished data)• Sizes of adults, ODFW angling data from Trail Bridge Reservoir and T.B. tailrace in 2003,28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-3

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputFecundityExamples of potentially usefultypes of data[good]• age/size structure of the adultpopulation [good]• age/size at first spawning [good]• information on age/sizerelationships from literature [ok]Size/age at sexual maturitySize/age data can be used topredict the number of eggsdeposited for spawning females,assuming that size/fecundityrelationships are established (seebelow)Types of data:• size distribution of adult females[best]• distribution of sizes at given agesor average size at age [ok]Available local information(including information that may result from relicensing studies)and trapping data from Trail Bridge Reservoir in 1992, 1999, and 2004 (ODFW 1992a,1999a, and 2004b; unpublished data).Sizes of adults, angling and trapping data, 2001-2004, Cougar Reservoir, South ForkMcKenzie and Cougar Reservoir (ODFW 2001a, 2002b, 2003b, and 2004a; unpublished data)• Numbers of fish observed during individual spawning surveys conducted by USDA ForestService and ODFW, from the Upper McKenzie River above Trail Bridge in 1998 and 2003(USDA Forest Service 1998a and 2003b, unpublished data)Data from relicensing studies• spawning surveys• scale analysis• Vaki RiverWatcher• angling dataExisting local information• Approximate sizes of probable spawning bull trout, from Vaki RiverWatcher data; see aboveexisting local information re: the known number of spawnersData from Relicensing Studies• Scale analysis• PIT tag analysis28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-4

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputHabitat quantityExamples of potentially usefultypes of dataSize/fecundity relationships Thisinformation will be used toestimate the number of eggs for afemale spawning population of agiven size distribution or averagesize.Types of data:hatchery or any other records offecundity (size-specific best)Area of available spawninghabitat• Direct input into the populationdynamics model, will helpdetermine the maximum numberof spawners possible undercurrent habitat conditions.Types of data:• number and areas of individualgravel patches [best]• relationships between usablespawning habitat area anddischarge [best]• observed locations of spawning[good]Available local information(including information that may result from relicensing studies)Existing Local Information•Data from Relicensing Studies•Existing local information• General observed spawning locations (i.e., creek name, and above/below culverts); seeexisting local information re: known number of spawners above• Quantified areas of potential spawning gravels for 6-12 in trout and >12 in trout, SweetwaterCreek, 1991 (Cameron and Paquette 1991)• Specific observed spawning locations from the upper McKenzie River (Kink Creek to T.B.Reservoir), Sweetwater Creek, and Smith River, 1997 (USDA Forest Service 1997a, 1997band 1997c; unpublished data)• Specific observed spawning locations; spawning survey observations, USDA Forest Serviceand ODFW, from the Upper McKenzie River above Trail Bridge in 1993, 1995, and 1998(USDA Forest Service 1993a, 1995a, and 1998a; unpublished data), Anderson Creek in 1995and 1998 (USDA Forest Service 1995b and 1998b, unpublished data), Upper South ForkMcKenzie/Roaring River in 1995 and 1998 (USDA Forest Service 1995d and 1998c,unpublished data)• Number and size of patch areas in Carmen Bypass reach during existing flows and spill flowsin 2003 (Stillwater Sciences 2004b)Data from relicensing studies• Aquatic Habitats and Instream Flows study• Spawning surveys• Fluvial Geomorphic Process and Channel Morphology study28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-5

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputReddarea/dimensionsRedd defense timeExamples of potentially usefultypes of dataWould be an input into the Escape5.1 sub-model to help determinethe maximum density of spawners.Types of data:• approximate redd areas and/ordimensions based on spawningsurveys [best]Based on current information wedon’t believe bull trout femalescommonly defend constructedredds, but are interested in anydata that pertains to this.Types of data:average time or distribution oftimes that a female defends herredd [best]Life-stage: Eggs-to-emergent fry.Survival rate Redd permeabilityPermeability is a measure ofintragravel flow, and thusspawning gravel quality. Will beused to help predict survival toemergence.Types of data:• redd permeability measurementsat known redds (in conjunctionwith survival rates, if possible)[best]• redd permeability measurementsat potential spawning sitesAvailable local information(including information that may result from relicensing studies)Existing local informationData from Relicensing Studies• Spawning surveys; including measurements of reddsExisting local information• ODFW PIT tag data from Trail Bridge Reservoir, Sweetwater Creek, and Trail Bridgetailrace, 2003-2004 (ODFW 2004d, unpublished data)• ODFW PIT tag data from South Fork McKenzie and Cougar Reservoir (ODFW 2001a,2002b, 2003b, and 2004a; unpublished data)• Fish behavior observations: USDA Forest Service spawning survey observations in OlallieCreek (USDA Forest Service 2004c, unpublished data)Data from relicensing studies• Spawning surveys• PIT tag dataExisting local information• Estimated D 50 for spawning patches, in Carmen Bypass reach during existing flows and spillflows in 2003 (Stillwater Sciences 2004b)Data from relicensing studies• Spawning surveys• Instream Flows and Habitat Availability Study28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-6

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of data[good]• if no permeability measurements,data on substrate size distributionwithin redds [good]• data on substrate size distributionwithin potential spawninggravels [ok]EmergenceThis data could help us to establisha more direct link betweennumbers of eggs and number of fryproduced under current conditions.Available local information(including information that may result from relicensing studies)Existing Local Information•Data from Relicensing Studies•Types of data:• fry emergence trapping data (inassociation with some measureof substrate gravel quality, ifpossible) [best]• data on sand deposition in redds(i.e., sand layers forming whichcould prevent emergence) afterfreshets occur [best]• frequency, duration, andmagnitude of sand-transportingevents that occur post-reddconstruction[best]• percent fines or sand in redds[good]• percent fines or sand in potentialspawning gravels [ok]28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-7

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of dataEgg deposition-to-emergencetimingEgg-to-emergence timing isimportant because it willdetermine how long eggs or alevinare vulnerable to entombing eventsor redd superimposition.Types of data:• egg-to-emergence timingmeasured as a function oftemperature [best]• temperature time-series recordedduring spawning season [best]Redd scouring potentialWill help determine the amount ofegg or alevin loss expected atmoderate to high flows.Types of data:• discharges at which scour wouldbe expected and correspondinglocation-specific depths of scour[best]• patches or areas susceptible toscour at given discharges [best]• discharge records [good]Available local information(including information that may result from relicensing studies)Existing local information• General temperature requirements for hatching (Goetz 1989, as cited in EWEB 2002)• Water temperatures in Sweetwater Creek, near Hwy. 126 from 1999-2003, and in the upperMcKenzie River (300 ft downstream of Kink Creek confluence) from 1998-2003 (USDAForest Service 2003d, unpublished data)• Water temperatures in the McKenzie River sub basin from FLIR imagery and groundtruthing(Torgersen et al. 1999)Local Sources Needed• Goetz, F. A. 1989. Biology of the bull trout, Salvelinus confluentus: a literature review.USDA Forest Service, Willamette National Forest, Eugene, Oregon. [as cited in EWEB 2002(as Willamette National Forest 1989)]Data from Relicensing Studies• Temperature data in streamsExisting local information• USGS gage data, McKenzie River: at outlet of Clear Lake from 1913-1915 and 1948-present,below Trail Bridge dam from 1961-present, near Vida from 1925-present, at McKenzieBridge from 1910-1994, and Smith River above Smith River Reservoir from 1961-present(USGS 2004, unpublished data)Data from relicensing studies• Flow monitoring in bypass reaches• Potential bed mobility study in relation to redd scour potential (as decided by a DecisionPoint)• Habitat availability study; identification of suitable spawning patches28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-8

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of dataRedd dewatering potentialWill help determine the amount ofegg or alevin loss due to flowfluctuations.Types of data:• observations of redd dewatering[best]• discharge records thatcorrespond with timing andlocation of dewatering events[best]• observations regardingdewatering of potential spawningsites and correspondingdischarge changes [good]Temperatures during incubationand alevin developmentNecessary to assess whether thereis evidence for alevin mortality orreduced condition due to highwater temperaturesTypes of data:• relationships of alevin size andsurvival to temperature [best]• temperature data recorded duringincubation [good]Available local information(including information that may result from relicensing studies)Existing local information• USGS gage data, McKenzie River: at outlet of Clear Lake from 1913-1915 and 1948-present,below Trail Bridge dam from 1961-present, near Vida from 1925-present, at McKenzieBridge from 1910-1994, and Smith River above Smith River Reservoir from 1961-present(USGS 2004, unpublished data)• Observations of redd dewatering in fall 2003 and 2004: Stillwater Sciences 2004b, and R.Rivera, pers. comm., 2004).Data from relicensing studies• Spawning surveys• Hydraulic Regimes study• Habitat availability and Instream Flows studyExisting Local Information• Optimal incubation temperatures (Goetz 1989, as cited in EWEB 2002)• Water temperatures in Sweetwater Creek, near Hwy. 126 from 1999-2003, and in the upperMcKenzie River (300 ft downstream of Kink Creek confluence) from 1998-2003 (USDAForest Service 2003d, unpublished data)Data from Relicensing Studies• Temperature data in streams28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-9

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential model Examples of potentially usefulAvailable local informationinputtypes of data(including information that may result from relicensing studies)Life-stages: Emergent fry to adults. There are 3 basic types of data needed to estimate life-stage specific survival: (1) data related to carrying capacity, (2)density-independent mortality after a carrying capacity bottleneck, and (3) predation mortality occurring after a carrying capacity bottleneck. For example ina hypothetical stream a large number of fry may emerge from the gravels, but the carrying capacity of fry may be 10% of the number that emerged. Theremaining 90% either emigrate to available habitat elsewhere or more likely die. Mortality that occurs after the carrying capacity bottleneck can either bedensity-independent (e.g., as a result of high summer water temperatures) or density-dependent (e.g., as result of predation). Below is a list of the type ofdata that could be used to estimate mortality. Although the model considers each life-stage separately, we have listed all the types of data that would beuseful in one list to avoid repetition.Life-stage-Specificcarrying capacity(density-dependentmortality)Observed densities instream andin the reservoirTypes of data:• observed densities by habitattype and location [best]• electrofishing or snorkel surveydata [good]Existing local information• Peak numbers of bull trout observed during snorkel surveys of pools in the mainstemMcKenzie R. (Olallie landing to Paradise campground) from 1994-1998, and in the SouthFork McKenzie R. (Roaring River to 1.6 km upstream of Cougar crossing) from 1995-1998(Taylor and Reasoner 1998)• Juvenile area densities and numbers (by fast, slow, and pocket type habitats) based onsnorkeling in Anderson Creek in 1999; estimated number and size of juveniles observed atIko Springs based on snorkeling in the Middle Fork Willamette River in 1999; and peaknumbers of bull trout observed during snorkel surveys of pools in the mainstem McKenzie R.(Olallie landing to Paradise campground) from 1994-1999, and in the South Fork McKenzieR. (Roaring River to 1.6 km upstream of Cougar crossing) from 1995-1999 (Taylor andReasoner 2000)• Juvenile area densities in pocket habitat for Anderson Creek in 1999 and 2000, and OlallieCreek in 2000, based on snorkeling; number of juvenile bull trout observed in mainstemMcKenzie River in 2000; number and density of bull trout observed in the Middle ForkWillamette River at Iko Springs based on snorkeling in 2000; and peak number of bull troutobserved during snorkel surveys in the South Fork McKenzie R. (Roaring River to 1.6 kmupstream of Cougar crossing) from 1995-2000 (Taylor and Ziller 2000)• Number of juvenile bull trout observed in mainstem McKenzie River in 2001, and numberand size range of bull trout observed in the Middle Fork Willamette River in 2001, based onsnorkeling (Taylor 2003)• Snorkel data from Middle Fork Willamette, maximum size of fish observed in 2002, and sizerange and number of fish observed in 2001 (USDA Forest Service 2003a)• Snorkel data from surveys on Anderson Creek in winter, 1998, age class and count; UpperMcKenzie River pool below Trail Bridge dam in 2002 and 2003, approximate sizes andcount; McKenzie River mainstem at MP 44 (near Anderson Creek) in 1998, sizes and count(USDA Forest Service 1998e, 2002a, and 2003e, unpublished data)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-10

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of dataAvailable local information(including information that may result from relicensing studies)• Presence/absence data, and fish sizes, based on snorkel data from biological stream probes onnumerous creeks in the McKenzie and Blue River Ranger districts (USDA Forest Service1991a-e, 1992b-k, 1993b, 1994a-i, 1997d-e, and 1998f-g; unpublished data)• Presence/absence, and sizes based on occurrences of bull trout, summaries of findings fromsnorkel, electrofishing, and foot surveys from 1991-2001, numerous streams (USDA ForestService 2001a, unpublished data)• Numbers and sizes, based on angling (released and illegal catch), and biological surveys inTrail Bridge Reservoir, Horse Creek, McKenzie River below Trail Bridge, and Olallie Creekin 1991and 1992; and from South Fork McKenzie River, mainstem McKenzie River (near S.Fork), and Cougar Reservoir in 1989, 1991, and 1992 (USDA Forest Service 1992a,unpublished data)• Scuba data from surveys on Trail Bridge Reservoir from 1991-1993 and Carmen Reservoir in1992; counts, sizes, and locations (USDA Forest Service 1991f, 1992l, and 1993c;unpublished data)• Snorkel data, with numbers and estimated sizes from effectiveness monitoring of sidechannels in Deer Creek in 1991 (USDA Forest Service 1994j, unpublished data), Buck Creekfrom 1993-1997 (USDA Forest Service 1996a and 1997f, unpublished data), Horse Creek in1992 (USDA Forest Service 1992m, unpublished data), Paradise Creek in 1995 (USDAForest Service 1995e, unpublished data), from passage in Olallie Creek in 1997 (USDAForest Service 1997e, unpublished data), and transplants in Sweetwater Creek in 1993, 1995,1997, and 2001 (USDA Forest Service 1993d, 1995f, 1997g and 2001b; unpublished data)• Juvenile area densities in Anderson Creek in 1991 and 1992, based on snorkeling (USDAForest Service 1993e)• Adult fish movement data from 1998-2000, based on radio tracking in the mainstemMcKenzie River below Trail Bridge, and Cougar Reservoir/S. Fork McKenzie from 1998-2000 (Taylor and Reasoner 1998, Taylor and Reasoner 2000 and Taylor and Ziller 2000)• Adult fish movement data from 2001-2004, based on radio tracking in Cougar Reservoir/S.Fork McKenzie (ODFW 2001a, 2002b, 2003b, and 2004a; unpublished data)Data from relicensing studies• Snorkel surveys• Population estimates based on mark-recapture of PIT-tagged fish28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-11

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputLife-stage-specificdensityindependentmortalityExamples of potentially usefultypes of dataSuitable habitat quantityinstream and in the reservoirThis measure, in combination withmaximum densities for suitablehabitat, will help determinecarrying capacity.Types of data:• quantity of available summerrearing habitat at variousdischarges• substrate embeddedness [best]• LWD and other refuge habitat[best]• substrate sizes [ok]Mortality rateDensity-independent mortality rateof emergent fry, late fry, juveniles,and sub adult/adult life-stages.Types of data:• electrofishing or snorkel surveydata comparing spring or earlysummer numbers of fry orjuveniles to late-summernumbers [good]• evidence of mortality due to highwater temperatures [good]• entrainment rates and mortalityrates due to entrainment [good]• mortality due to stranding [good]• fishing mortality [creel survey,and hook-and-line mortality dataare best] [best]Available local information(including information that may result from relicensing studies)Data from relicensing studies• Aquatic Habitats and Instream Flows study• Large Woody Debris Dynamics studyExisting local information• Snorkel survey data comparing spring or early summer numbers to late-summer numbers;numbers of fish observed during snorkel surveys from January to October, 1999, from IkoSprings on the Middle Fork Willamette River (Taylor and Reasoner 2000)• Estimated entrainment mortality in Cougar Reservoir (Taylor 2000)• Documentation of mortality and sizes of fish due to illegal angling catch, Trail BridgeReservoir in 1991 and 1992 (USDA Forest Service 1992a, unpublished data)Data from Relicensing Studies• Flow Fluctuations and Stranding study• Entrainment study• Snorkel surveys28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-12

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputPredationmortality (densitydependent)BioenergeticsExamples of potentially usefultypes of data• evidence of mortality due todisease• any information on mortality dueto fishing would be important forsubadult/adult life-stagesMortality rateDensity-dependent predationmortality rate of emergent fry, latefry, juveniles, and sub adult/adultlife-stages.• estimated predation rates [best]• stomach sampling data [best]• timing of emigration to thereservoir [best]• size at emigration to thereservoir [best]• size-specific predation rates inthe reservoir [best]Timing of and size at emigrationwill help determine the effect ofpredation on juveniles. Directinformation on predation is best, asare any other data directlyinforming mortality rate.Food availability and feedingbehavior instream and in thereservoirTypes of data:• food availability data:information on instreamAvailable local information(including information that may result from relicensing studies)Existing local information• Age class (fry/YOY, 1+ and 2+) and timing of emigration, 1993 to 2004; average, minimum,and maximum sizes of fry in 2003 and 2004, all based on RST trapping at Anderson Creekfrom 1993-2004 (USDA Forest Service 2004d-f, unpublished data)• Size (mean and range) at and timing of emigration to the South Fork McKenzie/CougarReservoir; RST at Roaring River (ODFW 2001a, 2002b, 2003b, and 2004a; unpublisheddata)Data from Relicensing Studies• Migrant trapping data• Reservoir sampling (proposed in 2005)Existing local information• Macroinvertebrate information (Aquatic Biology Associates 1999)• Juvenile fish numbers and sizes (potential prey), based on trap net data from Trail BridgeReservoir in 1992, 1999, and 2004 (ODFW 1992a, 1999a, 2004c; unpublished data)• Juvenile fish numbers and sizes (potential prey), based on Scuba data from surveys on TrailBridge Reservoir from 1991-1993 (USDA Forest Service 1991f, 1992l, and 1993c;unpublished data)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-13

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of datamacroinvertebrate standing cropsand production [best]• stomach sampling data [best]• information on standing cropsand production of prey species inTrail Bridge Reservoir (e.g.,zooplankton, fish larvae,macroinvertebrates) [best]• size-specific food habitsinformation (i.e., at what size dobull trout become piscivorous?)[best]Size-specific food habitsinformation is essential indetermining whether foodavailability may be more limitingthan space.Fish growth rates instream andin the reservoirTypes of data:• size-specific growth rateinformation based on observedchanges in size of individualsover time or size at age (inconjunction with fish densitydata best) [best]• densities based on electrofishingor snorkel surveys, inconjunction with PIT taginformation [good]• electrofishing data comparingspring or early summer sizes toAvailable local information(including information that may result from relicensing studies)Data from relicensing studies• Water Quality-macroinvertebrate samples• Reservoir sampling (proposed for 2005)Existing local information• Size-specific growth rates of PIT-tagged fish from S Fork McKenzie/Cougar Reservoir from2001-2004 (ODFW 2001a, 2002b, 2003b, and 2004a; unpublished data)• ODFW PIT tag data from Trail Bridge Reservoir, Sweetwater Creek, and Trail Bridgetailrace from 2003-2004 (ODFW 2004b, unpublished data) and (M. Wade, ODFW, pers.comm., 2004)Data from relicensing studies• PIT-tag recapture data• Snorkel surveys28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-14

FINAL REPORT Carmen-Smith Hydroelectric Project FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential modelinputExamples of potentially usefultypes of datalate-summer sizes [good]The best data would be forindividual growth rates. If densitydata are available for areas withknown tagged individuals, thiscould help assess the relationshipbetween growth rate and density,and/or if growth is densitydependentin any way.Available local information(including information that may result from relicensing studies)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardB-15

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendix CExisting local information for Chinook salmon populationdynamics modelTablesTable C-1. Potential spring Chinook salmon model parameters and relevant available information orinformation anticipated to be collected in the Relicensing studies. ...................................... C-1Copyright © 2006 Eugene Water & Electric Board - the following Appendix C to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report:Appendix CExisting local information for Chinook salmon populationdynamics model

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable C-1. Potential spring Chinook salmon model parameters and relevant available information or information anticipated to be collected inthe Relicensing studies.Potentialmodel inputExamples of potentially usefultypes of dataAvailable local information(including information that may result from relicensing studies)Life-stage: Spawning. The goal of this section of the model is to predict the number of eggs that are successfully deposited in the gravel for differentnumbers of spawners, i.e., a spawner-to-egg stock-production curve. To do this we need an estimate of fecundity, and mortality due to redd superimposition.Number ofspawnersKnown number of spawnersThis type of data can be used totest model predictions andallows assessment of year-toyearvariability.Types of data:• Estimates of spawningescapement [best]• Spawning surveys/redd counts[good]• Sex ratio of spawners [good]Existing local Information• Daily adult and jack passage counts of from Willamette Falls Fishway from 2001–2002 and 2004(ODFW 2001b, 2002b, 2004d,; unpublished data)• USDA Forest Service and ODFW redd counts from the Upper McKenzie River above TrailBridge in 1997–1998 and in the Smith River bypass reach in 1997 (USDA Forest Service 1997aand 1998a, unpublished data)• Snorkel data from surveys on Upper McKenzie River pool below Trail Bridge dam in 2002 and2003 (USDA Forest Service 2002a and 2003e, unpublished data)• Estimated run size for the McKenzie River from 1946–1986 (Howell et al. 1988)• Estimated run size for the McKenzie River for 1947 (Mattson 1948)• Sex ratio for fish processed in the McKenzie River Hatchery for 1947 (Mattson 1948)• Escapement over Leaburg Dam from 1986–1990 (Hagey 1991)• Number and distribution of spawning observations for the McKenzie River for 1989 (Hardin-Davis et al. 1991)• Redd counts, including number and distribution, above the Carmen-Smith Spawning Channelmigrant trap, from 1961–1993 (Smith 1993)• Number and sex ratio of adults entering the Carmen-Smith Spawning Channel from 1961–1993(Smith 1993)• Redd counts for the McKenzie River sub-basin from 1958–1993 (Smith 1993)• Redd counts in Lost Creek for 1958, 1965, 1969, from 1971–1972, 1988, and from 1992–1993(Smith 1993)• Aerial redd count surveys for the McKenzie River below the Walterville intake and upstream anddownstream of Leaburg Dam, including percentage of count below Hayden Bridge, from 1966–1993 (Smith 1993)• Carcass survey data for the lower McKenzie River from 1969–1977 (Smith 1993)• Escapement over Leaburg Dam for 1994 and 1995 (M Wade, ODFW, pers. comm., as cited inWillis et al. 1995)• Aerial and ground survey redd counts, including date and location, for the McKenzie River subbasinfor 1996 (Grimes et al. 1996)• Spawning survey data by location, including counts of live fish, carcasses, and redds in theMcKenzie River sub-basin for 1996 (Grimes et al. 1996)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-1

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputExamples of potentially usefultypes of dataTemporal distribution ofspawning runDates and temporal pattern ofspawning. Is the temporaldistribution normal or skewed?Knowing this information willhelp us determine how manypotential spawners are able tosuccessfully spawn and hasimplications for reddsuperimposition. A shortwindow of redd constructioncould mean there is more likelyto be an even distribution ofspawners; a longer window ofredd construction allows for agreater opportunity for reddsuperimposition.In addition, wewould like to compare theAvailable local information(including information that may result from relicensing studies)• Sex ratio, location, and date of carcasses sampled during spawning surveys in the McKenzieRiver sub basin for 1996 (Grimes et al. 1996)• Estimated run size, including Leaburg Dam counts, redd counts, hatchery returns, and sportcatch, for the McKenzie River from 1970–2003 (ODFW 2004d)• Aerial spawning survey, including counts of live fish, redds, and carcasses, below Leaburg Damfor 2001 (Downey and Murtagh 2001)• Redd counts, including density/mi, for the McKenzie River above Leaburg Dam from 1968–1997(EWEB 2002)• Redd counts for the Carmen-Smith Spawning Channel from 1968–2002 (EWEB 2002)• Escapement over Leaburg Dam and McKenzie River hatchery returns from 1970–2001 (EWEB2002)• Redd count data above and below Leaburg Dam for 1970–1999 (EWEB 2002)• Distribution of redds and carcasses in the McKenzie River sub basin from 1996–1998 and 2000–2002 (Shroeder et al. 2003)Data from relicensing studies• Spawning SurveysExisting local information• Daily adult and jack passage counts of from Willamette Falls Fishway from 2001–2002 and 2004(ODFW 2001b, 2002b, 2004d; unpublished data)• Average monthly percentage of the adult annual run passing Leaburg Dam from 1970–1986(Howell et al. 1988)• Comparison of egg take timing in the McKenzie River from 1902–1907 and 1984–1985 (Howellet al. 1988)• Date of entry into the Carmen-Smith Spawning Channel for 1961 (Smith 1993)• General information for timing of adult migration and spawning in the McKenzie River (NOAAFisheries 2003)Data from relicensing studies• spawning surveys• Vaki RiverWatcher detections• PIT tag analysis28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-2

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputExamples of potentially usefultypes of datatemporal distribution of Chinooksalmon with bull trout toevaluate the potential for intraspecificredd superimposition.Types of data:• Spawning timing curves [best]• Spawning surveys/redd counts[good]• Dates of beginning, end, andpeak of upstream migration orspawning [ok]The best data for describingtemporal distribution would beactual curves of numbers ofspawning fish over time; lessvaluable, but still useful datacould include beginning, peak,and end times for the run.Age/size structure ofpopulation. This informationwill be used to estimate thenumber of mature females in theadult population.Types of data:• Age/size-specific probabilitiesof spawning [best]• Data on sizes of spawningadults (preferably at knownages) [good]• Age/size structure of the adultpopulation [good]• Age/size at first spawning[good]Available local information(including information that may result from relicensing studies)Existing local information• Male maturity rates at age 3,4, and 5 and female maturity rates at age 5 and 6 for experimentalreleases of varying fish size from the McKenzie and Dexter/Oakridge hatcheries for 1975–1989brood years (Cramer et al. 1996)• Age structure for McKenzie River spring Chinook salmon returns from 1996–1997 (Lindsay etal. 1997 as cited in Myers et al. 2003)• General information regarding age structure for returning adults to the McKenzie River sub basin(Smith 1993)Data from relicensing studies28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-3

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputFecundityHabitat quantityExamples of potentially usefultypes of data• Information on age/sizerelationships from literature[ok]Size/age at sexual maturitySize/age data can be used topredict the number of eggsdeposited for spawning females,assuming that size/fecundityrelationships are established (seebelow)Types of data:• Size distribution of adultfemales [best]• Distribution of sizes at givenages or average size at age[ok]Size/fecundity relationshipsThis information will be used toestimate the number of eggs fora female spawning population ofa given size distribution oraverage size.Types of data:• Hatchery Or Any OtherRecords Of Fecundity (Size-Specific Best)Area of available spawninghabitatDirect input into the populationdynamics model, will helpdetermine the maximum numberof spawners possible undercurrent habitat conditions.Available local information(including information that may result from relicensing studies)Existing local information• Male maturity rates at age 3,4, and 5 and female maturity rates at age 5 and 6 for experimentalreleases of varying fish size from the McKenzie and Dexter/Oakridge hatcheries for 1975–1989brood years (Cramer et al. 1996)• Age structure for McKenzie River spring Chinook salmon returns from 1996–1997 (Lindsay etal. 1997 as cited in Myers et al. 2003)• General information regarding age structure for returning adults to the McKenzie River sub basin(Smith 1993)Data from relicensing studiesExisting local information• Average female size and estimated fecundity (based on length-fecundity relationship) for springChinook salmon in the Carmen-Smith Spawning Channel for 1961–1967 (Hagey 1968)• Average female size and estimated fecundity for spring Chinook salmon in the Carmen-SmithSpawning Channel for 1961–1980 (Smith 1993)• McKenzie River spawning ground surveys indicating mean female carcass size in 1996 (Grimeset. al 1996)Data from relicensing studiesExisting local information• Number and size of patch areas in Carmen Bypass reach during existing flows and spill flows in2003 (Stillwater Sciences 2004b)• USFWS habitat surveys conducted throughout the McKenzie River sub basin including estimatesof spawning carrying capacity based on available habitat discharge data, barrier information,water temperature, gradient, and general habitat quality data such as bed composition, LWDavailability, and pool frequency (Parkhurst et al. 1950)• Total number and percentage of redds by reach for the Carmen-Smith Spawning Channel from28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-4

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputReddarea/dimensionsExamples of potentially usefultypes of dataTypes of data:• Number and areas ofindividual gravel patches [best]• Relationships between usablespawning habitat area anddischarge [best]• Observed locations ofspawning [good]Would be an input into theEscape 5.1 submodel to helpdetermine the maximum densityof spawners.Available local information(including information that may result from relicensing studies)1961–1977, 1987–1991, and 1993 (Smith 1993)• Accessible and inaccessible prime spawning river kilometers located within the McKenzie subbasin (McElhany et al. 2003)• Available spawning area for the McKenzie River from Hendricks Bridge to the Smith RiverBridge based on substrate size classes comparing data from 1938 to 1991 (Sedell et al. 1992)• USDA Forest Service and ODFW redd counts, including specific locations, from the UpperMcKenzie River above Trail Bridge in 1997–1998 (USDA Forest Service 1997a and 1998a,unpublished data) and in the Smith River bypass reach in 1997 (USDA Forest Service 1997c)Data from relicensing studies• Aquatic Habitats and Instream Flows study• Spawning surveys• Fluvial Geomorphic Process and Channel Morphology studyExisting local informationData from relicensing studies• Spawning surveys; including measurements of reddsTypes of data:• Approximate redd areas and/ordimensions based on spawningsurveys [best]Redd defense time Types of data:• Average time or distribution oftimes that a female defends herredd [best]Existing local informationData from relicensing studies• Spawning surveys• PIT tag data28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-5

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential Examples of potentially usefulmodel inputtypes of dataLife-stage: Eggs-to-emergent fry.Survival rate Redd permeabilityPermeability is a measure ofintragravel flow, and thusspawning gravel quality. Willbe used to help predict survivalto emergence.Types of data:• Redd permeabilitymeasurements at known redds(in conjunction with survivalrates, if possible) [best]• Redd permeabilitymeasurements at potentialspawning sites [good]• If no permeabilitymeasurements, data onsubstrate size distributionwithin redds [good]• Data on substrate sizedistribution within potentialspawning gravels [ok]EmergenceThis data could help us toestablish a more direct linkbetween numbers of eggs andnumber of fry produced undercurrent conditions.Types of data:• Fry emergence trapping data(in association with somemeasure of substrate gravelquality, if possible) [best]• Data on sand deposition inredds (i.e., sand layers formingAvailable local information(including information that may result from relicensing studies)Existing local information• Estimated D 50 for spawning patches, in Carmen Bypass reach during existing flows and spillflows in 2003 (Stillwater Sciences 2004b)• Seasonal mean permeability data in the Carmen-Smith Spawning Channel for 1961–1967 (Hagey1968)Data from relicensing studies• Spawning surveys• Instream Flows and Habitat Availability StudyExisting local information• Total and percent survival of egg to emigrating fry from trap data in the Carmen-Smith SpawningChannel for 1961–1967 (Hagey 1968)• Total and percent survival of egg to emigrating fry from trap data in the Carmen-Smith SpawningChannel for 1961–1973 (Smith 1993)Data from relicensing studies28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-6

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputExamples of potentially usefultypes of datawhich could preventemergence) after freshets occur[best]• Frequency, duration, andmagnitude of sand-transportingevents that occur post-reddconstruction[best]• Percent fines or sand in redds[good]• Percent fines or sand inpotential spawning gravels[ok]Egg deposition-to-emergencetimingEgg-to-emergence timing isimportant because it willdetermine how long eggs oralevin are vulnerable toentombing events or reddsuperimposition.Types of data:• Egg-to-emergence timingmeasured as a function oftemperature [best]• Temperature time-seriesrecorded during spawningseason [best]Available local information(including information that may result from relicensing studies)Existing local information• Emergence timing in the South Fork McKenzie River in relation to USGS temperature data for1992 (Homolka and Downey 1995 as cited in NOAA Fisheries 2003)• Water temperatures in the McKenzie River sub basin from FLIR imagery and ground-truthing(Torgersen et al.1999)• Water temperatures in the upper McKenzie River (300 ft downstream of Kink Creek confluence)from 1998-2003 (USDA Forest Service 2003f, unpublished data)• Acceleration of emergence based on alteration of temperatures by local dams (USDA ForestService 1995f, as cited in NMFS and USDA Forest Service 2002)• General temperature requirements for Chinook salmon incubation (Piper et al. 1982 as cited inEWEB 2002• Water temperatures in various mainstem McKenzie River and tributary locations for 1937–1938(Sedell et al. 1992)Local sources needed• Homolka, K., and T. W. Downey. 1995. Assessment of thermal effects on salmon spawning andfry emergence, upper McKenzie River, 1992. Information Report 95-4. Oregon Department ofFish and Wildlife, Fish Research and Development Section, Corvallis. [as cited in NOAAFisheries 2003]Data from relicensing studies• Migrant trapping• Temperature data in streams28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-7

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputExamples of potentially usefultypes of dataRedd scouring potentialWill help determine the amountof egg or alevin loss expected atmoderate to high flows.Types of data:• Discharges at which scourwould be expected andcorresponding locationspecificdepths of scour [best]• Patches or areas susceptible toscour at given discharges[best]• Discharge records [good]Redd dewatering potentialWill help determine the amountof egg or alevin loss due to flowfluctuations.Types of data:• Observations of redddewatering [best]• Discharge records thatcorrespond with timing andlocation of dewatering events[best]• Observations regardingdewatering of potentialspawning sites andcorresponding dischargechanges [good]Available local information(including information that may result from relicensing studies)Existing local information• USGS gage data, McKenzie River: at outlet of Clear Lake from 1913-1915 and 1948-present,below Trail Bridge dam from 1961-present, near Vida from 1925-present, at McKenzie Bridgefrom 1910-1994, and Smith River above Smith River Reservoir from 1961-present (USGS 2004,unpublished data)Data from relicensing studies• Flow monitoring in bypass reaches• Potential bed mobility study in relation to redd scour potential (as decided by a Decision Point)• Habitat availability studies; identification of suitable spawning patchesExisting local information• USGS gage data, McKenzie River: at outlet of Clear Lake from 1913-1915 and 1948-present,below Trail Bridge dam from 1961-present, near Vida from 1925-present, at McKenzie Bridgefrom 1910-1994, and Smith River above Smith River Reservoir from 1961-present (USGS 2004,unpublished data)• Observations of redd dewatering in fall 2003 and 2004: Stillwater Sciences 2004b, and R. Riverapers. comm., 2004).Data from relicensing studies• Spawning surveys• Hydraulic Regimes study• Instream Flows and Aquatic Habitats study28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-8

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputExamples of potentially usefultypes of dataTemperatures duringincubation and alevindevelopmentNecessary to assess whetherthere is evidence for alevinmortality or reduced conditiondue to high water temperaturesTypes of data:• Relationships of alevin sizeand survival to temperature[best]• Temperature data recordedduring incubation [good]Available local information(including information that may result from relicensing studies)Existing local information• Water temperatures in the McKenzie River sub basin from FLIR imagery and ground-truthing(Torgersen et al. 1999)• Water temperatures in the upper McKenzie River (300 ft downstream of Kink Creek confluence)from 1998-2003 (USDA Forest Service 2003f, unpublished data)• Seven-day average maximum water temperatures in the McKenzie River below Trail BridgeReservoir and at McKenzie Bridge from 1993–1994 (USDA Forest Service 1995g)Local sources needed• Temperature records for incubation periods used to determine time of fry emergence from thegravel in the Carmen-Smith Spawning Channel for 1962–1967 [referenced in Hagey 1968]Data from relicensing studies• Temperature data in streams28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-9

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotential Examples of potentially usefulAvailable local informationmodel inputtypes of data(including information that may result from relicensing studies)Life-stages: Emergent fry to smolts. There are 3 basic types of data needed to estimate life-stage specific survival: (1) data related to carrying capacity, (2)density-independent mortality after a carrying capacity bottleneck, and (3) predation mortality occurring after a carrying capacity bottleneck. For example ina hypothetical stream a large number of fry may emerge from the gravels, but the carrying capacity of fry may be 10% of the number that emerged. Theremaining 90% either emigrate to available habitat elsewhere or more likely die. Mortality that occurs after the carrying capacity bottleneck can either bedensity-independent (e.g., as a result of high summer water temperatures) or density-dependent (e.g., as result of predation). Below is a list of the type ofdata that could be used to estimate mortality.Life-stage andseason-specificcarrying capacity(densitydependentmortality)Life-stages includefry, pre-smoltjuveniles, andresiduals/precocialsObserved densities instreamand in the reservoirTypes of data:• Observed densities by habitattype and location and season[best]• Electrofishing or snorkelsurvey data [good]Existing local information• Snorkel data, with numbers and estimated age classes from effectiveness monitoring of sidechannels in Buck Creek from 1993–1997 (USDA Forest Service 1996a and 1997f, unpublisheddata), Horse Creek in 1992 (USDA Forest Service 1992m, unpublished data), Paradise Creek in1995 (USDA Forest Service 1995e, unpublished data), and Lost Creek in 1992 and 1998 (USDAForest Service 1992f-g and 1998g; unpublished data)• Juvenile releases into the McKenzie River from all sources for 1960–1984 broods (Howell et al.1988)• Average monthly catch of fry (2 in) at Leaburg Canal (1948), South Fork McKenzie River (1959–1960),and Leaburg trap (1980–1983) (Howell et al. 1988)• Snorkel data, with numbers/ft 2 by habitat type for diverted and undiverted segments of theMcKenzie River in the vicinity of the Leaburg Walterville Project (Hardin-Davis et al. 1991)• Fry and smolt production from the Carmen-Smith Spawning Channel for 1962–1965 broods(Smith 1993)• Migrant trap data, with numbers and timing for fry (

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputLife-stage-specificdensityindependentmortalityExamples of potentially usefultypes of dataSuitable habitat quantityinstream and in the reservoirThis measure, in combinationwith maximum densities forsuitable habitat, will helpdetermine carrying capacity.Types of data:• Quantity of available summerrearing habitat at variousdischarges• Substrate embeddedness [best]• LWD and other refuge habitat[best]• Substrate sizes [ok]Mortality rateDensity-independent mortalityrate of emergent fry, juveniles,and smolts.Types of data:• Electrofishing or snorkelsurvey data comparing springor early summer numbers offry or juveniles to late-summernumbers [good]• Evidence of mortality due tohigh water temperatures [good]• Entrainment rates andmortality rates due toentrainment [good]• Mortality due to strandingAvailable local information(including information that may result from relicensing studies)Data from relicensing studies• Snorkel surveys• Population estimates based on mark-recapture of PIT-tagged fishExisting local information• General rearing habitat condition information for Chinook salmon in the McKenzie River subbasin (LCOG 1996)Data from relicensing studies• Aquatic Habitats and Instream Flows study• Large Woody Debris Dynamics studyExisting local information• Estimated entrainment mortality in Cougar Reservoir (Taylor 2000)Data from relicensing studies• Flow Fluctuations and Stranding study• Entrainment study• Snorkel surveys28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-11

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputPredationmortality(densitydependent)Examples of potentially usefultypes of data[good]• Fishing mortality [creelsurvey, and hook-and-linemortality data are best] [best]• Evidence of mortality due todiseaseMortality rateDensity-dependent predationmortality rate of emergent fry,juveniles, and smolts.• Estimated predation rates[best]• Stomach sampling data [best]• Timing of emigration to thereservoir [best]• Size at emigration to thereservoir [best]• Size-specific predation rates inthe reservoir [best]Timing of and size at emigrationwill help determine the effect ofpredation on juveniles. Directinformation on predation is best,as are any other data directlyinforming mortality rate.Existing local informationAvailable local information(including information that may result from relicensing studies)Data from relicensing studies28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-12

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputBioenergeticsExamples of potentially usefultypes of dataFood availability and feedingbehavior instream and in thereservoirTypes of data:• Food availability data:information on instreammacroinvertebrate standingcrops and production [best]• Stomach sampling data [best]• Information on standing cropsand production of prey speciesin trail bridge reservoir (e.g.,zooplankton, fish larvae,macroinvertebrates) [best]• Size-specific food habitsinformation [best]Size-specific food habitsinformation is essential indetermining whether foodavailability may be morelimiting than space.Available local information(including information that may result from relicensing studies)Existing local informationData from relicensing studies28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-13

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputExamples of potentially usefultypes of dataFish growth rates instreamand in the reservoirTypes of data:• Size-specific growth rateinformation based on observedchanges in size of individualsover time or size at age (inconjunction with fish densitydata best) [best]• Densities based onelectrofishing or snorkelsurveys, in conjunction withpit tag information [good]• Electrofishing data comparingspring or early summer sizes tolate-summer sizes [good]Available local information(including information that may result from relicensing studies)Existing local information• Mean fork length of juvenile spring Chinook salmon seined in the McKenzie River in spring andsummer from 2000–2003 (Shroeder et al. 2003)Data from relicensing studiesThe best data would be forindividual growth rates. Ifdensity data are available forareas with known taggedindividuals, this could helpassess the relationship betweengrowth rate and density, and/orif growth is density-dependent inany way.Life-stages: Smolts to returning adults.Life-stage andseason-specificcarrying capacity(densitydependentmortality)Observed densities ofmigrating smolts andmigrating adultsTypes of data:• Observed densities by habitattype and location [best]• Electrofishing or snorkelsurvey data [good]Existing local information• Estimated carrying capacity for spawners based on USFWS habitat surveys in the McKenzieRiver sub basin from 1937–1938 (Parkhurst et al. 1950)• Comparison of large pool frequencies in Horse Creek and the South Fork McKenzie River for1941 and 1990 (Cramer et al. 1996)• Comparison of large pool frequencies for the McKenzie River and selected tributaries from1937–1938 and 1991 (Sedell et al. 1992)• Number and frequency/mi of resting pools for various reaches of the McKenzie River (Sedell et28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-14

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputExamples of potentially usefulAvailable local informationtypes of data(including information that may result from relicensing studies)• Adult holding habitat [good] al. 1992)• General adult holding information for the Lower McKenzie River (ODFW 1990)• Annual production of smolts for release into the McKenzie River for 1984–1993 brood years (J.Leppink, ODFW, pers. comm., as cited in Willis et al 1995)• Leaburg Dam smolt (>60 mm average) catch data, including numbers and timing from 1986–1992 (Willis et al. 1995)• Migrant trap data, with numbers and timing for juveniles at Leaburg Dam from 1980–1983(Zakel and Reed 1984)• Smolt migration timing at Leaburg Dam averaged from data for 1981, 1982, 1987, and 1999(EWEB 2002 based on data from Zakel and Reed 1984 and Homolka 1990)Life-stage-specificdensityindependentmortalityMortality rateDensity-independent mortalityrate of smolts and adults.Types of data:• Evidence of mortality due tohigh water temperatures [good]• Entrainment rates andmortality rates due toentrainment [good]• Mortality due to stranding[good]• Fishing mortality [creelsurvey, and hook-and-linemortality data are best] [best]• Ocean harvest rates [good]• Evidence of mortality due todisease [good]• Size of smolts [good]Any information on mortalitydue to fishing would beData from relicensing studies• Snorkel surveys• Population estimates based on mark-recapture of PIT-tagged fishExisting local information• Estimated angler effort and catch of smolts and adults in the McKenzie River for 1983(Hutchinson and Hooton 1990)• Catch records, including creel survey estimates for 1974 and 1983, tag return data for 1963–1984,and punch card data from 1970–1986 for the McKenzie River (Howell et al. 1988)• Catch records above and below Leaburg Dam from 1970–2001 (ODFW 2002c)• Estimated run size, sport catch rate, and harvest rate in the McKenzie River from 1983–2001(ODFW 2001b, unpublished data)• Estimates of run size and sport catch rate in the McKenzie River from 1974–1994 (Cramer et al.1996)• Harvest rate estimates for adult escapement to the McKenzie River form 1974–1995) (Cramer etal. 1996)• General estimates of pre-spawning mortality for adults holding in freshwater over the summer(Cramer et al. 1996)• Pre-spawning mortality rates at the McKenzie holding rack and the Walterville Canal rack from1946 and 1947 (Mattson 1948)• Pre-spawning mortality rates for the Carmen–Smith Spawning Channel from 1961–1987 (Smith1993)• Pre-spawning mortality rates for the McKenzie River from 2001–2003 (Schroeder et al. 2003)• Projected sport fishery harvest rates for the McKenzie River based on data from 1985–1994(ODFW 2001b, unpublished data)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-15

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputPredationmortality(densitydependent)Examples of potentially usefultypes of dataimportant for smolt and adultlife-stages.Mortality rateDensity-dependent predationmortality rate of smolts andadults.• Estimated predation rates[best]• Stomach sampling data [best]• Timing of emigration from thereservoir [best]• Size at emigration from thereservoir [best]• Size-specific predation rates inthe mainstem duringemigration, in the ocean, andduring spawning migrations[best]• Predation rates on adults bymammals in the estuary;predator densities in theestuary [good]• Ocean predation rates (sizespecific)[good]Timing of and size at emigrationwill help determine the effect ofpredation on smolts. Directinformation on predation is best,as are any other data directlyinforming mortality rate.Available local information(including information that may result from relicensing studies)Data from relicensing studies• Flow Fluctuations and Stranding study• Entrainment study• Snorkel surveysExisting local informationData from relicensing studies• Migrant trapping data• Reservoir sampling (proposed in 2005)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-16

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputAge-specificmaturationProportion of fishby sub basinExamples of potentially usefultypes of dataAge/size structure ofpopulation. This informationwill be used to estimate the ageand number of migrating smoltsand returning adults in thepopulation.Types of data:• Age and size distribution ofsmolts [best]• Age/size structure of the adultpopulation [best]• Estimated age-specificmaturation probabilities or agestructure of adult returns [best]• Information on age/sizerelationships from literature[ok]Types of data:• Number of returning adults bysub-basin [best]Available local information(including information that may result from relicensing studies)Existing local information• Male maturity rates at age 3,4, and 5 and female maturity rates at age 5 and 6 for experimentalreleases of varying fish size from the McKenzie and Dexter/Oakridge hatcheries for 1975–1989brood years (Cramer et al. 1996)• Age structure for McKenzie River spring Chinook salmon returns from 1996–1997 (Lindsay etal. 1997 as cited in Myers et al. 2003)• General information regarding age structure for returning adults to the McKenzie River sub basin(Smith 1993)Data from relicensing studiesExisting local information• Distribution and run size estimates for the Willamette River Basin comparing data from 1947 todata from 1980–1989 (Willis et al. 1995)• Distribution of spawners recovered from South Santiam spring Chinook salmon released belowWillamette Falls for 1975–1978 brood years (Cramer et al. 1996)• Estimated returns to the McKenzie River for escapement over Willamette Falls from 1970–1994(Cramer et al. 1996)• Estimated returns to Willamette River sub basins for 1947 (Mattson 1948)• Distribution of redds and carcasses in the McKenzie River sub basin from 1996–1998 and 2000–2002 (Schroeder et al. 2003)• Spawning surveys , including distribution and counts of live fish, carcasses, and redds within theMcKenzie River sub basin for 1996 (Grimes et al. 1996)Data from relicensing studies28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-17

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportPotentialmodel inputIntrabasinstraying ratesExamples of potentially usefultypes of dataTypes of data:• Straying rates among subbasins[best]• Hatchery records indicatingorigin of returning adults[good]Available local information(including information that may result from relicensing studies)Existing local information• Numbers and percentages of strays recovered in the McKenzie River from 1978–1985 (Howell etal. 1988)• Percent of strays from escapement data at the Leaburg Dam from 1997–2000 (ODFW 2002c)• Migration patterns from radio tracking data in the McKenzie River for 1990 (EA Engineering1991)• Adult returns of marked fry and smolts to the Carmen-Smith Spawning Channel for 1964–1967brood years (Smith 1993)• Straying rates and recovery sites for marked juveniles from Willamette Basin Hatcheries releasedbelow Willamette Falls for 1975–1989 brood years (Cramer et al. 1996)• Estimates of in-basin straying rates in the McKenzie River for 1990 and 1994–1995 (Willis et al.1995 citing M. Wade, pers. comm., ODFW)• Release and recovery site information for marked spring Chinook salmon for brood years 1991–1992 (Grimes et al. 1996)• Recovery site information for marked smolts released into the lower Willamette basin for broodyear 1996 (Schroeder et al 2003)Data from relicensing studies28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardC-18

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendix DBull trout population model parameters and valuesTablesTable D-1. Bull trout population dynamics model parameters and values under currentconditions............................................................................................................... D-1Table D-2. Escape 5.1 sub-model parameters for bull trout in the Study Area.......................... D-8Table D-3. Bull trout population dynamics model parameters and values assuming flowconditions that resulted in the highest estimated habitat availability in the CarmenBypass Reach....................................................................................................... D-10Table D-4. Bull trout population dynamics model parameters and values assuming hypolimneticreleases in Smith Bypass Reach result in lower summer water temperatures.. ... D-11Table D-5. Bull trout population dynamics model parameters and values assuming fish passageat Smith Dam.. ..................................................................................................... D-12Table D-6. Bull trout population dynamics model parameters and values assuming large woodydebris enhancements in Carmen Bypass Reach and Sweetwater Creek. ............. D-16Copyright © 2006 Eugene Water & Electric Board - the following Appendix D to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report:Appendix DBull trout population model parameters and values

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable D-1. Bull trout population dynamics model parameters and values under current conditions.Sub Reach Life-stage Parameter Value Source CommentsInitialODFW 2004a (JulypopulationsizeSept.) quarterlyreport for CougarReservoirCarmenBypass ReachsubreachAdults (> 400 mmFL)to female spawnersFemale spawnerto deposited eggsSex ratio ofspawners (female tomale)Frequency ofSpawningProportion of femalespawners inSweetwater CreekProportion of femalespawners in CarmenBypass ReachProportion of femalespawners in SmithBypass ReachProportion of femalespawners in SmithRiver above SmithReservoirSuitable spawninggravel area1:10.80.30.70.00.0Mark Wade(September reportfor CougarReservoir, 2005)PIT tag data fromCougar Reservoir(M. Wade, pers.comm., 3 Nov 2004,ODFW)2003 to 2005 PIT tagdata in Study Area(Stillwater Sciences2006a)2004 spawningsurveys (StillwaterSciences 2006a)216 m 2 Habitat mapping(Stillwater Sciences2006b) at 160 cfs.Mean redd area 1.8 m 2 of redd dimensions(Stillwater SciencesTotal station surveys2006a)Range of 1:1 to 1.4:1Sex ratio of adult population is not known. A ratio of 1:1 is areasonable estimate, based on lack of any convincing evidence tothe contrary. A ratio of 1.4:1 has been estimated in the SouthFork McKenzie River (ODFW 2004a). In Roaring River, theyfound 23 females/15 males in 2004 and in the SF McKenzie 23females/25 males in 2005 so far .Cougar data indicates annual spawning. PIT tag data in StudyArea indicates proportion of the population annual, and proportionbi-annual. Thus far it appears that about half the Trail Bridgepopulation is biennial, and half is annual.Assumes one female per redd, and that half of unknown redds inCarmen Bypass Reach are bull trout.Estimated using bull trout spawning guild. 145 m 2 added toestimate for available habitat in Carmen Bypass Reach in habitatunit #1,which was not included in habitat mapping study.Total station surveys conducted in Carmen Bypass Reach.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-1

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsDensity-independentEscape 5.12768rate of increase (r)submodel- this studyPermeability Range from 0 to 0.61.analysis (StillwaterSciences 2006c)Deposited eggs-toemergentfryEmergent fry toresident early fry (

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsSweetwaterCreeksubreachResident late fry (45–100 mm FL) to age1+ and age 2+juveniles (100–250mm FL)Age 1+ and age 2+juveniles (100–250mm FL) to Subadults(250–400 mmFL)Previous subadults(250–400 mm FL) tonew adults (1st year> 400 mm FL)Female spawnerto deposited eggsMaximum densityfor juvenilesSuitable habitatDensity-independentsurvival rateSuitable habitat 0Suitable habitat area 0Suitable spawninggravel areaDirect observation45 fish/100m 2 snorkel surveys(Stillwater Sciences2006b)4,054 m 2 Habitat mapping(Stillwater Sciences2006b) at 160 cfs0.8 AssumptionHabitat mapping(Stillwater Sciences2006b)Habitat mapping(Stillwater Sciences2006b)162 m 2 Habitat mapping(Stillwater Sciences2006b)Mean redd area 0.5 m 2 of redd dimensions(Stillwater SciencesTotal station surveys2006a)Density-independentrate of increase (r)2768Escape 5.1submodel- this studyMaximum density of juvenile bull trout occupying habitat mappedas salmonid juvenile rearing guild, based on snorkel validationsurveys in Carmen Bypass Reach. Highest two densities observedwere 45 and 88 fish/100m 2 . The density for all juvenile salmonidsand char (mostly rainbow trout, cutthroat trout, and bull trout) was132 fish/100m 2. The second highest density of bull trout observed(45 fish/100m 2 ) was selected as a value to reflect the ecologicalinteraction between bull trout and other juvenile salmonids. Thedensity of 45 fish/100m 2 was observed where bull trout were inassociation with rainbow trout and cutthroat trout.Based on salmonid juvenile rearing guildPredation and other sources of mortality during rearing.Based on bull trout adult rearing guild. Not modeled for thissubreach.Based on bull trout adult rearing guild. Not modeled for thissubreach.Estimated using bull trout spawning guild.Total station surveys conducted in Sweetwater Creek. Model wasalso run using redd area of 1.82 m 2 , based on redd area measuredin Carmen Bypass Reach.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-3

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsPermeability Range from 0 to 0.29.analysis (StillwaterSciences 2006c)Deposited eggs toemergent fryEmergent fry toresident early fry (

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsTrail BridgeReservoirResident late fry (45–100 mm FL) to age1+ and age 2+juveniles (100–250mm FL)Age 1+ and age 2+juveniles (100–250mm FL) to Subadults(250–400 mmFL)Previous subadults(250–400 mm FL) tonew adults (1st year> 400 mm FL)Migrant emergentfry (< 45 mm)Migrant emergentfry to early fry (< 45mm FL)Maximum densityfor juvenilesDirect observation45 fish/100m 2 snorkel surveys(Stillwater Sciences2006b)Suitable habitat 2637 m 2 Habitat mapping(Stillwater Sciences2006b)Density-independentsurvival rateSuitable habitat 0Suitable habitat area 0Density-independentsurvival rate (duringmigration to TrailBridge or Smithreservoirs)Maximum densityfor early fryMaximum density of juvenile bull trout occupying habitat mappedas salmonid juvenile rearing guild, based on snorkel validationsurveys in Carmen Bypass Reach. Highest two densities observedwere 45 and 88 fish/100m 2 . The density for all juvenile salmonidsand char (mostly rainbow trout, cutthroat trout, and bull trout) was132 fish/100m 2. The second highest density of bull trout observed(45 fish/100m 2 ) was selected as a value to reflect the ecologicalinteraction between bull trout and other juvenile salmonids. Thedensity of 45 fish/100m 2 was observed where bull trout were inassociation with rainbow trout and cutthroat trout.Based on salmonid juvenile rearing guild0.8 Assumption Predation and other sources of mortality during rearing.0.05Habitat mapping(Stillwater Sciences2006b)Habitat mapping(Stillwater Sciences2006b)Percentage of earlyfry migrating fromCarmen BypassReach and capturedat rotary screw trapthisstudyElectrofishing (Copeand Morris 2001,Cope et al. 2002,84 fish/100 m 2 Cope 2003, Cope2004)Snorkeling (Goetz1994)Based on bull trout adult rearing guild. Not modeled for thissubreach.Based on bull trout adult reservoir rearing guild. Not modeled forthis subreach.Assumes these fry have reached early fry size before leaving.Includes predation. Estimate based on the fraction of migrantcaptured at rotary screw trap in lower Carmen Bypass Reach, andresident fry (assumed at carrying capacity, with density of 84fish/100 m 2 , suitable habitat area at 205 cfs) in comparison withthe expected number of emergent fry (given 35 bull trout reddsobserved in 2004, fecundity 2,839 eggs/female), and survival fromegg to emergence (0.32, based on permeability results notedabove).Maximum density was selected. Four highest density valuesreported were 38, 51, 82, and 84 fish/100 m 2 .28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-5

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsSuitable habitat area 10,489 m 2 Habitat mapping(Stillwater Sciences Based on bull trout fry reservoir rearing guild.2006b)Migrant early fryMigrant early fry (

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsSuitable habitat area 121,181 m 2 Habitat mapping(Stillwater Sciences2006b)Age 1+ and age 2+juveniles (100–250mm FL) to Subadults(250–400 mm FL)Previous subadults(250–400 mm FL) tonew adults (1st year> 400 mm FL)New adults (> 400mm FL) to old adults(2 nd year or more >400 mm FL)Density-independentsurvival rateMaximum densityfor subadults andadults0.01 Assumption0.000633 fish/m 2This study0.00084 fish/m 2 D.Ratliff, PGE,pers.comm, 2005Suitable habitat area 175,409 m 2 (Stillwater SciencesHabitat mapping2006b)Density-independentsurvival rate (annual)Density-independentsurvival rate(subadults)Density-independentsurvival rate (adults)0.40.660.84Program MARK PITtag mark-recapturedata (StillwaterSciences 2006a)Program MARK PITtag mark-recapturedata (StillwaterSciences 2006a) inTrail BridgeReservoir.Program MARK PITtag mark-recapturedata (StillwaterSciences 2006a) inTrail BridgeReservoir.Based on bull trout juvenile reservoir rearing guild.Assumption that survival is low for fry based on extensive surveysthat resulted in no observed fry in Trail Bridge Reservoir.Includes mortality from stranding, entrainment, and predation.Downs et al. (2005) also found migrant fry did not contribute toadult population.Shared carrying capacity between adults and subadults;TB densities = 0.000443 based on 114 fish/255,164 m2 (entirereservoir area), and 0.000633 fish/ m 2 in suitable habitat.Lake Billy Chinook salmon densities = based on 13,331fish/15,800,000 m 2Based on bull trout adult reservoir rearing guild.Includes mortality from predation, stranding, entrainment, nonmortalitylosses (e.g., emigration). Based on estimates of threeperiods.Includes mortality from predation, angling, stranding,entrainment, non-mortality losses (e.g., emigration). 0.66 (CI of0.46 to 0.89) when fitted to subadults only.When subadults and adults combined: 2004: 0.70 CI of 0.55 to0.82) 2005: 0.94 (CI of 0.73 to 0.99)Includes mortality from predation, angling, stranding,entrainment, non-mortality losses (e.g., emigration).2004: 0.75 (CI of 0.52 to 0.89)2005: 0.84 (CI of 0.66 to 0.94)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-7

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable D-2. Escape 5.1 sub-model parameters for bull trout in the Study Area.Life-stage Parameter Value SourceNotes on model sensitivity,confidence, and certaintyFemaleSpawners toDeposited Eggs(Escape input)Individual Gravel Patch AreasAverage redd area[egg_region=disturbed_region=averageredd area]Redd defense area versus redd area[defended_region=4*disturbed_region]Redd defense timeTemporal distribution of spawning run[spawning_time=6*SD]Egg development timeSum of individual patchareas=457 m 22004 spawning surveys(Stillwater Sciences 2006a)1.82 m 2 2004 spawning surveys(Stillwater Sciences 2006a)4X the redd area Burner 19513.5 dStandard deviation = 7 d(spawning_time=42 d)160 d2004 spawning surveys(Stillwater Sciences 2006a)2004 spawning surveys(Stillwater Sciences 2006a)2004 spawning surveys(Stillwater Sciences 2006a)Rotary screw trapping resultsfrom Stillwater Sciences 2006bBased on Lower Carmen Bypass survey. Data inputinto Escape 5.1 is the amount of area for eachindividual patch.Observed redd dimensions in Carmen Bypass ReachDefended region is equal to 4 times the disturbedregion (redd size).Based on data from Lower Carmen Bypass Reach;assumes that half the time it takes to construct theredd is spent in redd defense.Based on Lower Carmen Bypass data;7 September to 7 October, peak during the thirdweek in September.Based on a truncated normal distribution using thestandard deviation and mean of the dates when reddswere created. Can assume same timing in SpawningChannel.Based on Lower Carmen Bypass Reach data;Number of days from fertilization to emergence.Estimated at least 165 d based on first spawningobserved late September 2004, first fry observed in2005 in early March.Rotary screw trapping fromUSFS 2005Estimated 210 d based on first spawning observed inearly October and first fry observed in mid May2005.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-8

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportLife-stage Parameter Value SourceNotes on model sensitivity,confidence, and certaintySize/fecundity relationshipslog(fecundity)=-9.1933+2.7274log(FL),FecundityMean fecundity:2839 eggs/femaleMcPhail and Baxter (1996) andmean size and fecundity fromMacDonald (1985)), and meanspawner size (from study areasampled fish)where FL is the fork length (mm)Regression based on raw data from the originalliterature sources would be much better, if possible,although preliminary analyses did reveal a relativelystrong log-log relationship (r 2 =0.946).Mean fecundity is based on mean FL of 537 mm.Size/age at sexual maturity=537 mm; includes bothmales and females, may be underestimating size offemales, since smaller fish likely to be males.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-9

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable D-3. Bull trout population dynamics model parameters and values assuming flow conditions that resulted in the highest estimatedhabitat availability in the Carmen Bypass Reach. Values are shown for parameters that vary from those used for current conditions, all othervalues are assumed to be the same (shown in Table D-1).Sub Reach Life-stage Parameter Value Source CommentsCarmen BypasssubreachFemale spawner to deposited eggsSuitable spawninggravel areaby flow (cfs)205: 305 m 2 Habitat mapping (Stillwater320: 253 m 2 Sciences 2006b)Estimated using bull troutspawning guild.Emergent fry to resident early fry (< 45 mmFL)Suitable habitat 931 m 2 Habitat mapping (StillwaterSciences 2006b) at 205 cfsBased on trout fry rearingguild.Resident early fry (< 45 mm FL) to resident latefry (45–100 mm FL) (June/July)Suitable habitat 2,397 m 2 Habitat mapping (StillwaterSciences 2006b) at 205 cfsBased on Chinook salmonfry rearing guild.Resident late fry (45–100 mm FL) to age 1+ andage 2+ juveniles (100–250 mm FL)Suitable habitat 4780 m 2 Habitat mapping (StillwaterSciences 2006b) at 205 cfsBased on salmonid juvenilerearing guild28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-10

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable D-4. Bull trout population dynamics model parameters and values assuming hypolimnetic releases in Smith Bypass Reach result in lowersummer water temperatures. Values are shown for parameters that vary from those used for current conditions, all other values are assumedto be the same (shown in Table D-1).Sub Reach Life-stage Parameter Value Source CommentsInitialpopulation sizeSmithBypasssubreachAdults (> 400 mm FL)to female spawnersFemale spawner to depositedeggsProportion of femalespawners inSweetwater CreekProportion of femalespawners in CarmenBypass ReachProportion of femalespawners in SmithBypass ReachSuitable spawninggravel area0.250.250.5Assumption22 m 2 Habitat mapping(Stillwater Sciences2006b) at 20 cfsCurrently 70% of females spawn in Carmen BypassReach. Assumes that half will still spawn in CarmenBypass Reach, and 25% in each of the other twotributaries.Estimated using bull trout spawning guild, assuming 20cfs base flow as part of a minimum flow to decreasesummer water temperaturesEmergent fry to resident earlyfry (< 45 mm FL)Resident early fry (< 45 mm FL)to resident late fry (45–100 mmFL) (June/July)Resident late fry (45–100 mmFL) to age 1+ and age 2+juveniles (100–250 mm FL)Suitable habitat 2,753 m 2 (Stillwater Sciences2006b) at 20 cfsHabitat mappingSuitable habitat 4,829 m 2 2006b) at 50 cfsHabitat mapping(Stillwater SciencesSuitable habitat 7,587 m 2 (Stillwater SciencesHabitat mapping2006b)Based on trout fry rearing guild. Current base flowsduring spring (early fry rearing period) are 20 cfs.Based on Chinook salmon fry rearing guild. Assumes anincrease of summer base flows to 50 cfs with 45 cfs ofhypolimnetic release.Based on salmonid juvenile rearing guild. Assumes anincrease of summer base flows to 50 cfs with 45 cfs ofhypolimnetic release.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-11

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportInitialpopulation sizeTable D-5. Bull trout population dynamics model parameters and values assuming fish passage at Smith Dam. Values are shown forparameters that vary from those used for current conditions, all other values are assumed to be the same (shown in Table D-1).Sub Reach Life-stage Parameter Value Source CommentsProportion ofAdults (> 400 mmfemale spawners inFL)1.0 AssumptionSmith River aboveto female spawnersSmith ReservoirSmith Riverupstream ofSmithReservoirFemale spawnerto deposited eggsDeposited eggs-toemergentfryEmergent fry toresident early fry (

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsElectrofishing (Cope andMorris 2001, Cope et al.Maximum density 84 fish/100for late frym 2 2002, Cope 2003, Cope2004)Assumed to be the same as early frySnorkeling (Goetz 1994)Resident early fry ( 400 mm FL)Suitable habitat 0 m 2 (Stillwater SciencesHabitat mapping2006b)Densityindependentsurvival rateMaximum densityfor juveniles1,282 was mapped based on Chinook salmon fry rearing guild.Assumes that although physical habitat is available, watertemperatures preclude it’s use.0.80 Assumption Predation and other sources of mortality45fish/100m 2Direct observation snorkelsurveys (StillwaterSciences 2006b)Suitable habitat 3,137m 2 Habitat mapping(Stillwater Sciences2006b)Temperature analysis(Stillwater Sciences2006b)Densityindependent0.8 Assumptionsurvival rateSuitable habitat 0Suitable habitatarea0Habitat mapping(Stillwater Sciences2006b)Habitat mapping(Stillwater Sciences2006b)Maximum density of juvenile bull trout occupying habitat mappedas salmonid juvenile rearing guild, based on snorkel validationsurveys in Carmen Bypass Reach. Highest two densities observedwere 45 and 88 fish/100m 2 . The density for all juvenile salmonidsand char (mostly rainbow trout, cutthroat trout, and bull trout) was132 fish/100m 2. The second highest density of bull trout observed(45 fish/100m 2 ) was selected as a value to reflect the ecologicalinteraction between bull trout and other juvenile salmonids. Thedensity of 45 fish/100m 2 was observed where bull trout were inassociation with rainbow trout and cutthroat trout.3,137 m 2 mapped based on salmonid juvenile rearing guild.Temperature does not preclude habitat use.Predation and other sources of mortalityBased on bull trout adult rearing guild. Not modeled for thissubreach.Based on bull trout adult reservoir rearing guild. Not modeled forthis subreach.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-13

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsSmith ReservoirDensityindependentPercentage of early frymigrating from CarmenMigrant emergentsurvival rate0.05 Bypass Reach andfry (< 45 mm)(during migrationcaptured at rotary screwto Smith reservoir)trap- this studyMigrant emergentfry to early fry (< 45mm FL)Migrant early fryMigrant early fry (

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsMigrant late fry (45–100 mm FL) tojuveniles (100–250mm FL)Age 1+ and age 2+juveniles (100–250mm FL) to Subadults(250–400 mmFL)Previous subadults(250–400 mm FL) tonew adults (1st year> 400 mm FL)Previous subadults(250–400 mm FL) tonew adults (1st year> 400 mm FL)Maximum densityfor juvenilesSuitable habitatareaDensityindependentsurvival rateMaximum densityfor subadults andadultsSuitable habitatareaDensityindependentsurvival rate(annual)Densityindependentsurvival rate(subadults)Densityindependentsurvival rate(adults)45fish/100m 2Direct observation snorkelsurveys (StillwaterSciences 2006b)120,791 m 2 Habitat mapping(Stillwater Sciences2006b)0.01 Assumption0.000633fish/ m 2This studyHabitat mapping240,597m 2 (Stillwater Sciences2006b)Program MARK PIT tagmark-recapture data0.4(Stillwater Sciences2006a)0.660.84Program MARK PIT tagmark-recapture data(Stillwater Sciences2006a) in Trail BridgeReservoir.Program MARK PIT tagmark-recapture data(Stillwater Sciences2006a) in Trail BridgeReservoir.Maximum density of juvenile bull trout occupying habitat mappedas salmonid juvenile rearing guild, based on snorkel validationsurveys in Carmen Bypass Reach. Highest two densities observedwere 45 and 88 fish/100m 2 . The density for all juvenile salmonidsand char (mostly rainbow trout, cutthroat trout, and bull trout) was132 fish/100m 2. The second highest density of bull trout observed(45 fish/100m 2 ) was selected as a value to reflect the ecologicalinteraction between bull trout and other juvenile salmonids. Thedensity of 45 fish/100m 2 was observed where bull trout were inassociation with rainbow trout and cutthroat trout.Based on bull trout juvenile reservoir rearing guild.Shared carrying capacity between adults and subadults; based ondensity observed in Trail Bridge ReservoirBased on bull trout adult reservoir rearing guild.Includes mortality from predation, stranding, entrainment, nonmortalitylosses (e.g., emigration). Based on estimates of threeperiods.Includes mortality from predation, angling, stranding, entrainment,non-mortality losses (e.g., emigration). 0.66 (CI of 0.46 to 0.89)when fitted to subadults only.When subadults and adults combined: 2004: 0.70 CI of 0.55 to0.82) 2005: 0.94 (CI of 0.73 to 0.99)Includes mortality from predation, angling, stranding, entrainment,non-mortality losses (e.g., emigration).2004: 0.75 (CI of 0.52 to 0.89)2005: 0.84 (CI of 0.66 to 0.94)28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-15

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable D-6. Bull trout population dynamics model parameters and values assuming large woody debris enhancements in Carmen Bypass Reachand Sweetwater Creek.Sub Reach Life-stage Parameter Value Source CommentsInitialpopulation sizeCarmenBypassReachsubreachAdults (> 400 mm FL)to female spawnersFemale spawner todeposited eggsEmergent fry to residentearly fry (< 45 mm FL)Resident early fry (< 45mm FL) to resident latefry (45–100 mm FL)(June/July)Resident late fry (45–100mm FL) to age 1+ and age2+ juveniles (100–250 mmFL)Proportion offemale spawners inSweetwater CreekProportion offemale spawners inCarmen BypassReachProportion offemale spawners inSmith BypassReachSuitable spawninggravel areaSuitable habitat0.250.50.252004 spawning surveys(Stillwater Sciences 2006a)297 m 2 Habitat mapping (StillwaterSciences 2006b) at 160 cfs1,911 m 2 Habitat mapping (StillwaterSciences 2006b) at 205 cfs.Habitat mapping (StillwaterSciences 2006b) at 160 cfsSuitable habitat 3,641 m 2Suitable habitat6,346 m 2 Habitat mapping (StillwaterSciences 2006b) at 160 cfsAssumes one female per redd, andthat half of unknown redds in CarmenBypass Reach are bull trout.Estimated using bull trout spawningguild. 145 m 2 added to estimate foravailable habitat in Carmen BypassReach in habitat unit #1, which wasnot included in habitat mappingstudy. Also increased by a factor of1.5 over 80% of the reach based onlarge woody debris enhancements insummer 2005.Based on trout fry rearing guildincreased by a factor of 2.3 over 80%of the reach based on large woodydebris enhancements in summer 2005.Based on Chinook salmon fry rearingguild increased by a factor of 1.9 over80% of the reach based on largewoody debris enhancements insummer 2005.Based on salmonid juvenile rearingguild increased by a factor of 1.7 over80% of the reach based on largewoody debris enhancements insummer 2005.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-16

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source Comments223 m 2 Habitat mapping (StillwaterSciences 2006b)SweetwaterCreekFemale spawner todeposited eggsEmergent fry toresident early fry (< 45mm FL)Resident early fry (< 45mm FL) to resident latefry (45–100 mm FL)(June/July)Resident late fry (45–100mm FL) to age 1+ and age2+ juveniles (100–250 mmFL)Suitable spawninggravel areaHabitat mapping (StillwaterSciences 2006b)Suitable habitat 577 m 2Habitat mapping (StillwaterSciences 2006b)Suitable habitat 1,542 m 2Suitable habitat 4,128 m 2 Habitat mapping (StillwaterSciences 2006b)Based on bull trout spawning guild.Assumes large woody debrisenhancement results are similar to theincreases estimated for the CarmenBypass Reach (factor of 1.5).Based on trout fry rearing guild.Assumes large woody debrisenhancement results are similar to theincreases estimated for the CarmenBypass Reach (factor of 2.3).Based on Chinook salmon fry rearingguild. Assumes large woody debrisenhancement results are similar to theincreases estimated for the CarmenBypass Reach (factor of 1.9).Based on salmonid juvenile rearingguild. Assumes large woody debrisenhancement results are similar to theincreases estimated for the CarmenBypass Reach (factor of 1.7).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardD-17

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendix EChinook salmon population model parameters and valuesTablesTable E-1. Spring Chinook salmon population dynamics model parameters and values undercurrent conditions in the Study Area.........................................................................E-1Table E-2. Escape 5.1 sub-model parameters for spring Chinook salmon in the Study Area.....E-6Table E-3. Spring Chinook salmon population dynamics model parameters and values assumingflow conditions that resulted in the highest estimated habitat availability in theCarmen Bypass Reach...............................................................................................E-7Table E-4. Spring Chinook salmon population dynamics model parameters and values assumingflow conditions that resulted in the highest estimated habitat availability in SmithBypass Reach. ...........................................................................................................E-7Table E-5. Chinook salmon population dynamics model parameters and values assuming largewoody debris enhancements in Carmen Bypass Reach, and Smith Bypass Reach...E-8Table E-6. Spring Chinook salmon population dynamics model parameters and values assumingpassage at Smith Dam. ..............................................................................................E-9Table E-7. Spring Chinook salmon population dynamics model parameters and values undercurrent conditions in the Carmen-Smith Spawning Channel. .................................E-12Copyright © 2006 Eugene Water & Electric Board - the following Appendix E to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report:Appendix EChinook salmon population model parameters and values

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable E-1. Spring Chinook salmon population dynamics model parameters and values under current conditions in the Study Area.Sub Reach Life-stage Parameter Value Source CommentsInitial Returning adults toPopulation TB dam to adults Upstream passageSize passed above TB efficiency1.0damSmithBypassReachAdults (> 500 mm)passed to femalespawnersFemale spawnerto deposited eggsSex ratio (femalesto males) SpawningChannelSex ratio (femalesto males). Alllocations other thanSpawning ChannelPre-spawningmortality SpawningChannelPre-spawningmortality. Alllocations other thanSpawning ChannelProportion offemale spawners toCarmen BypassProportion offemale spawners toSmith BypassSuitable spawninggravel areaValue is 1.0 due to fish being trucked upstream of Trail BridgeDam.1:1.66 Smith 1993 Estimated in the Spawning Channel1:1Sex determination of alladults placed into TrailBridge (ODFW andStillwater Sciences 2006a)0.5 Assumption0.50.80.2PIT tag mark-resight data(Stillwater Sciences2006a)Spawning surveys(Stillwater Sciences2006a)7 m 2 Habitat mapping(Stillwater Sciences2006c) at 7 cfs.Mean redd area 0.9 m 2 redd dimensions(Stillwater SciencesTotal station surveys of2006a)Density-independentrate of increase4,936Escape 5.1 submodel thisstudyUse 1:1 for current conditions.Use 1:1.66 for passage scenarios.Assumed to be similar to pre-spawning mortality above TrailBridge Dam.Based on number of unique tags detected in spawning tributariesabove Trail Bridge Dam as compared with the number of fishreleased into Trail Bridge Reservoir.Assumes one female per redd, and that half of unknown redds inCarmen Bypass Reach are Chinook salmon.Estimated using Chinook salmon spawning guild. 7 m 2 added toestimate for available habitat in Smith Bypass Reach in habitat units#1-4, which were not included in habitat mapping study.Based on Chinook salmon fecundity and Escape 5.1 submodelresults.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-1

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsPermeability analysis(Stillwater Sciences2006d)CarmenBypassReachDeposited eggs-toemergentfryEmergent fry toresident fry (< 55mm)Resident fry toage 0+ juveniles(> 55 mm with nosigns of smolting)Age 0+ juvenile toage 1+ juvenileFemale spawnerto deposited eggsSurvival rate 0.5Maximum frydensityRelationship betweenpermeability and survivalbased on Chinook andcoho salmon (Tagart 1976,McCuddin 1977)208fish/100 m 2 Bjorn (1978)Suitable habitat area 8,135 m 2 Habitat mapping(Stillwater Sciences2006b) at 7 cfs.Density-independentsurvival rateMaximum juveniledensityRange from 0.36 to 0.63.Big Springs Creek, Idaho (as cited in Smith et al. 1985). Densitiesof 129 and 135 fish/ m 2 also reported in Bjornn 1978 and Bjornnand Reiser 1991, respectively.Estimated using Chinook salmon fry rearing guild. 7 cfs is currentsummer base flow.0.8 Assumption Mortality due to predation and other sources.4.2fish/100 m 2Snorkel surveyobservations (StillwaterSciences 2006a)7,000 m 2 Habitat mappingSuitable habitat area(Stillwater Sciences2006b) at 7 cfs.Density-independentsurvival rateDensity-independentsurvival rateSuitable spawning 212 m 2 Habitat mapping(Stillwater Sciencesgravel area2006b) at 160 cfs.Mean redd area 5.4 m 2 (Stillwater SciencesDensity-independentrate of increaseMaximum density of Chinook salmon juveniles occupying habitatmapped as salmonid juvenile rearing guild, based on snorkelvalidation surveys in Smith Bypass Reach. Highest two densitiesobserved were 4.2 and 8.3 fish/100m 2 . The density for all juvenilesalmonids and char (mostly rainbow trout, cutthroat trout, and bulltrout) was 132 fish/100m 2 in the Carmen Bypass Reach. Thesecond highest density of Chinook salmon observed (4.2fish/100m 2 ) was selected as a value to reflect the ecologicalinteraction between Chinook salmon and other juvenile salmonids.River reaches estimated using Chinook salmon juvenile rearingguild at current summer base flow.0.8 Mortality due to predation and other sources.0.75 Lestelle et al. 1996 Over winter survival2006a)4,813 Escape 5.1 submodel thisstudyEstimated using Chinook salmon spawning guild. 145 m 2 added toestimate for available habitat in Carmen Bypass Reach in habitatunit #1, which was not included in habitat mapping study.Total station surveys of redd dimensionsBased on bull trout parameters (r=0.97), and Chinook salmonfecundity. Will be updated.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-2

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsPermeability analysis(Stillwater Sciences2006d)Trail BridgeReservoirDeposited eggs-toemergentfryEmergent fry toresident fry (< 55mm)Resident fry to age0+ juveniles (> 55mm with no signs ofsmolting)Age 0+ juvenile toage 1+ juvenileMigrant emergentfry leaving Carmenor Smith bypassEmergent fry toresident fry (< 55mm)Survival rate 0.3Maximum frydensityRelationship betweenpermeability and survivalbased on Chinook andcoho salmon (Tagart 1976,McCuddin 1977)208fish/100m 2 Bjorn (1978)Suitable habitat area 2,081 m 2 Habitat mapping(Stillwater Sciences2006b) at 160 cfs.Density-independentsurvival rateMaximum juveniledensityRange from 0 to 0.61.Big Springs Creek, Idaho (as cited in Smith et al. 1985). Densitiesof 129 and 135 fish/ m 2 also reported in Bjornn 1978 and Bjornnand Reiser 1991, respectively.Estimated using Chinook salmon fry rearing guild.0.8 Mortality due to predation and other sources.4.2fish/100 m 2Snorkel surveyobservations (StillwaterSciences 2006a)Suitable habitat area 4,054 m 2 Habitat mapping(Stillwater Sciences2006b) at 160 cfsDensity-independentsurvival rateDensity-independentsurvival rateDensity-independentsurvival rate (duringmigration to TrailBridge Reservoir)Maximum frydensityMaximum density of Chinook salmon juveniles occupying habitatmapped as salmonid juvenile rearing guild, based on snorkelvalidation surveys in Smith Bypass Reach. Highest two densitiesobserved were 4.2 and 8.3 fish/100m 2 . The density for all juvenilesalmonids and char (mostly rainbow trout, cutthroat trout, and bulltrout) was 132 fish/100m 2. The second highest density of Chinooksalmon observed (4.2 fish/100m 2 ) was selected as a value to reflectthe ecological interaction between Chinook salmon and otherjuvenile salmonids.River reaches estimated using Chinook salmon juvenile rearingguild. Reservoir areas based on Chinook salmon fry reservoirrearing guild.0.8 Assumption Mortality due to predation and other sources.0.75 Lestelle et al. 1996 Over winter survival0.2511fish/100 m 2Percentage of early frymigrating from CarmenBypass Reach- this studyFry seining data (StillwaterSciences 2006a)Includes predation. Estimate based on the fraction of migrants andresident fry (assumed at carrying capacity, with density of 208fish/100 m 2 , suitable habitat area at 205 cfs) in comparison to theexpected number of emergent fry (given 34 Chinook salmon reddsobserved in 2004, fecundity (4,936 eggs/female), and survival fromegg to emergence (0.32, based on permeability results noted above).Calculated densities based on shoreline beach seining in TrailBridge Reservoir. The three highest values were 13, 126, and 511fish/100m 2 .28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-3

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsSuitable habitat area 10,489 m 2 (Stillwater Sciences Estimated using Chinook salmon fry rearing guild.Habitat mapping2006b)Density-independentAssume that survival of emergent fry is low in the reservoir, but that0.8 Assumptionsurvival ratethe duration of time from emergent fry to resident fry is short.Migrant fry leavingCarmen or Smithbypass0.2 Assumption Conservative value for survival, based on estimates of fry survival.Fry to age 0+juveniles (> 55 mmwith no signs ofsmolting)Age O+ juvenile toage 1+ juvenileAge 1+ juvenile tosmolt (55–>100 mm)Density-independentsurvival rate (duringmigration to TrailBridge Reservoir)Maximum juveniledensity220fish/100 m 2Piaskowski and Tabor2001Suitable habitat area 10,489 m 2 (Stillwater SciencesHabitat mapping2006c)Density-independentsurvival rateDensity-independentsurvival rateMaximum densityfor smolts0.52004-05 rotary screwtrapping (StillwaterSciences 2006a)0.75 Lestelle et al. 1996 Over winter survivalBradford (Dept. of Fish130 fish /100 m 2 and Oceans, W.VancouverLaboratory, pers. comm.)Suitable habitat area 10,489 m 2 (Stillwater SciencesHabitat mapping2006b)Density-independentsurvival rate0.52004-05 rotary screwtrapping (StillwaterSciences 2006a)Based on snorkel surveys in nearshore habitat of southern LakeWashington. Maximum density was observed in March, otherdensities reported by the authors include 80, 160, and 15 fish/100m 2 during April, May, and June, respectively.Estimated using Chinook salmon fry rearing guild.20% survival was estimated for fry to smolts, based on estimate offry out-migrating in 2004 vs. estimate of juveniles captured at TrailBridge tailrace. Assumes all juveniles captured at Trail BridgeTailrace rotary trap are migrants from Trail Bridge Reservoir.Includes mortality from stranding, entrainment, and predation. Theestimate of 20% survival was partioned for the model parametersinto survival from fry to juveniles (50%), juveniles to smolts (50%),and survival during passage at Trail Bridge Dam (80%).Assumed to be the same as for juveniles. Assumes no smoltsrearing in river reaches.Assumed to be the same as for juveniles. Assumes no smoltsrearing in river reaches.20% survival was estimated for fry to smolts, based on estimate offry out-migrating in 2004 vs. estimate of juveniles captured at TrailBridge tailrace. Assumes all juveniles captured at Trail BridgeTailrace rotary trap are migrants from Trail Bridge Reservoir.Includes mortality from stranding, entrainment, and predation. Theestimate of 20% survival was partioned for the model parametersinto survival from fry to juveniles (50%), juveniles to smolts (50%),and survival during passage at Trail Bridge Dam (80%).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-4

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsBelow Trail Fry from TrailBridge Dam Bridge Reservoir topassed fry entering0.8mainstemJuveniles from TrailBridge Reservoir tojuveniles enteringmainstemTotal smolts fromTrail BridgeReservoir to passedsmolts enteringmainstemPassed smoltsentering mainstem toreturning adults toTrail BridgeReservoirPassage survival atspillway or turbineDensity-independentsurvival rate0.80.8Bell (1981)0.05 Assumption20% survival was estimated for fry to smolts, based on estimate offry out-migrating in 2004 vs. estimate of juveniles captured at TrailBridge tailrace. Assumes all juveniles captured at Trail BridgeTailrace rotary trap are migrants from Trail Bridge Reservoir.Includes mortality from stranding, entrainment, and predation. Theestimate of 20% survival was partioned for the model parametersinto survival from fry to juveniles (50%), juveniles to smolts (50%),and survival during passage at Trail Bridge Dam (80%). Passagemortality of 20% is consistent with Bell (1981), which found arange of 1–46% mortalityAssumption, intended to provide the model with a loop back toreturning adults, but is not considered precise.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-5

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable E-2. Escape 5.1 sub-model parameters for spring Chinook salmon in the Study Area.Life-stage Parameter Value Source CommentsGravel patch areaSum of individualIndividual Gravel Patch Areaspatch areas=457 m 2 mapping, (StillwaterSciences 2004b, 2006b)Female Spawnersto Deposited Eggs(Escape input)Average redd area[egg_region=disturbed_region=average reddarea]Redd defense area versus redd area[defended_region=4*disturbed_region]Redd defense timeTemporal distribution of spawning run[spawning_time=6*SD]Egg development timeTotal station surveys of5.42 m 2 redd dimensions(Stillwater Sciences2006a)4X the redd area Burner (1951)10 dStandard deviation= 4.5 d195 d(Stillwater Sciences2006a), (FERC 1994)(Stillwater Sciences2006a)Spawning Surveys andRotary Screw Trapping(Stillwater Sciences2006a)Fecundity 4,936 eggs Hagey 1968From data in Lower Carmen Bypass Reach.Based on data from Lower Carmen Bypass Reach.Defended region is equal to 4 times the disturbed region(redd size).Observatins of spawning timing in the Carmen BypassReach, and the Tuolumne River.Based on data from Lower Carmen Bypass Reach, 7September to 7 October, peak during third week inSeptemberBased on Lower Carmen bypass spawning surveys androtary screw trapping results. Approximately 195 dbetween the first observed spawning adults and early frycaptured in the rotary screw trap.Based on relationships developed in the ColumbiaRiver. Likely a good approximation for the McKenzieRiver. Size/fecundity relationshipsY=267.82X-3,634, where X is female size in inches,assumed 32in fish.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-6

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable E-3. Spring Chinook salmon population dynamics model parameters and values assuming flowconditions that resulted in the highest estimated habitat availability in the Carmen Bypass Reach.Values are shown for parameters that vary from those used for current conditions; all other values areassumed to be the same (shown in Table E-1).Life-stage Parameter Value Source CommentsFemale spawnerto deposited eggsSuitablespawninggravel area289 m 2 Habitat mapping(Stillwater Sciences2006b) at 205 cfsEstimated using Chinook salmonspawning guild. 145 m 2 added toestimate for available habitat in CarmenBypass Reach in habitat unit #1, whichwas not included in habitat mappingstudy.Emergent fry toresident fry (< 55mm)Suitablehabitat area2,397 m 2 Habitat mapping(Stillwater Sciences2006b) at 205 CFSEstimated using Chinook salmon fryrearing guild.Resident fry to age0+ juveniles (> 55mm with no signs ofsmolting)Suitablehabitat area4,780 m 2 Habitat mapping(Stillwater Sciences2006b) at 205cfsRiver reaches estimated using Chinooksalmon juvenile rearing guild.Reservoir areas based on Chinooksalmon fry reservoir rearing guild.Table E-4. Spring Chinook salmon population dynamics model parameters and values assuming flowconditions that resulted in the highest estimated habitat availability in Smith Bypass Reach. Values areshown for parameters that vary from those used for current conditions; all other values are assumed tobe the same (shown in Table E-1).Life-stage Parameter Value Source CommentsProportion offemale spawners toCarmen Bypass0.7Adults (> 500 mm)passed to femalespawnersFemale spawner todeposited eggsEmergent fry to residentfry (< 55 mm)Resident fry to age 0+juveniles (> 55 mmwith no signs ofsmolting)Proportion offemale spawners toCarmen BypassSuitable spawninggravel areaSuitable habitatareaSuitable habitatarea0.3Spawning surveys(Stillwater Sciences2006a)Habitat mappingBy flow (cfs):120: 82 m 2 2006b)20: 22 m 2 (Stillwater Sciences8,135 m 2 Habitat mapping(Stillwater Sciences2006b) at 7 cfs7,587 m 2 Habitat mapping(Stillwater Sciences2006b) at 50 cfsAssumes that as spawninghabitat increases in SmithBypass Reach, additionalfemales will spawn there.20 cfs results in an increase inavailable habitat120 cfs is the flow thatmaximizes spawning habitat7 cfs is the flow thatmaximizes fry habitat (currentbase flow in summer)50 cfs the flow that maximizesjuvenile rearing habitat28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-7

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable E-5. Chinook salmon population dynamics model parameters and values assuming large woodydebris enhancements in Carmen Bypass Reach, and Smith Bypass Reach.Sub Reach Life-stage Parameter Value Source CommentsSmithBypassReachCarmenBypassReachFemale spawner todeposited eggsEmergent fry toresident fry (< 55 mmFL)Resident fry to age 0+juveniles (>55 mmwith no sign ofsmolting)Female spawner todeposited eggsEmergent fry toresident fry (< 55 mmFL)Resident fry to age 0+juveniles (>55 mmwith no sign ofsmolting)Suitable spawninggravel area9 m 2 Habitat mapping(Stillwater Sciences2006b) at 7 cfsHabitat mapping(Stillwater Sciences2006b) at 7 cfsSuitable habitat 14, 234 m 2Suitable habitat 10,958 m 2 (Stillwater SciencesHabitat mapping2006b) at 7 cfsSuitable spawninggravel area285 m 2 Habitat mapping(Stillwater Sciences2006b) at 160 cfsSuitable habitat 4,194 m 2 2006b) at 205 cfsHabitat mapping(Stillwater SciencesSuitable habitat 6,346 m 2 (Stillwater SciencesHabitat mapping2006b) at 160 cfsEstimated using Chinook salmonspawning guild. 7 m 2 added toestimate for available habitat inSmith Bypass Reach in habitatunits #1-4, which were notincluded in habitat mappingstudy.Increased by a factor of 1.4 over80% of the reach based on largewoody debris enhancements insummer 2005.Based on Chinook salmon fryrearing guild. Assumes largewoody debris enhancementresults are similar to theincreases estimated for theCarmen Bypass Reach (factor of1.9).Based on salmonid juvenilerearing guild. Assumes largewoody debris enhancementresults are similar to theincreases estimated for theCarmen Bypass Reach (factor of1.7).Estimated using bull troutspawning guild. 145 m 2 addedto estimate for available habitatin Carmen Bypass Reach inhabitat unit #1, which was notincluded in habitat mappingstudy. Also increased by afactor of 1.5 over 80% of thereach based on large woodydebris enhancements in summer2005.Based on Chinook salmon fryrearing guild increased by afactor of 1.9 over 80% of thereach based on large woodydebris enhancements in summer2005.Based on salmonid juvenilerearing guild increased by afactor of 1.7 over 80% of thereach based on large woodydebris enhancements in summer2005.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-8

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable E-6. Spring Chinook salmon population dynamics model parameters and values assuming passageat Smith Dam.Sub Reach Life-stage Parameter Value Source CommentsInitialProportion ofSmithSmith femaleBypassspawners to0.5ReachSmith BypassInitialSmithReservoirUpperSmithRiverSmith femalespawnersSpawners toSmith Reservoirto Upper SmithspawnersFemalespawner todepositedeggsProportion ofSmith femalespawners toSmith ReservoirPre-spawningmortality fromSmith Reservoirto upper SmithSuitablespawning gravelarea0.50.5AssumptionPIT tag mark-resightdata (StillwaterSciences 2006a)75 m 2 Habitat mapping(Stillwater Sciences2006b)Mean redd area 5.4 m 2 of redd dimensions(Stillwater SciencesTotal station surveys2006a)Densityindependentrateof increase4,936Escape 5.1 submodelthis studyPermeabilityanalysis (StillwaterSciences 2006d)This is an arbitrary valueassuming half of the fish willspawn in Smith Bypass asopposed to migrating to SmithReservoir.Based on number of unique tagsdetected in spawning tributariesabove Trail Bridge Dam ascompared with the number offish released into Trail BridgeReservoir. Assumed same forSmith Reservoir.Assumed to be the same as theCarmen Bypass Reach, sincegravel patch size is similar.Based on Chinook salmonfecundity.Deposited eggsto-emergentfryEmergent fry toresident fry (< 55mm)Survival rate 0.5Maximum frydensitySuitable habitatareaDensityindependentsurvival rateRelationshipbetweenpermeability andsurvival based onChinook and cohosalmon (Tagart1976, McCuddin1977)208fish/100m 2 Bjorn (1978)613 m 2 Habitat mapping(Stillwater Sciences2006b)0.8 AssumptionAssumed to be the same asSmith Bypass Reach.Big Springs Creek, Idaho (ascited in Smith et al. 1985).Densities of 129 and 135 fish/m 2 also reported in Bjornn 1978and Bjornn and Reiser 1991,respectively.Estimated using Chinooksalmon fry rearing guild.Mortality due to predation andother sources28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-9

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsResident fry toage 0+ juveniles(> 55 mm withno signs ofsmolting)Maximumjuvenile densitySuitable habitatarea4.2fish/100 m 2Snorkel surveyobservations(Stillwater Sciences2006a)1,583 m 2 Habitat mapping(Stillwater Sciences2006b)Based on observations in SmithBypass ReachRiver reaches estimated usingChinook salmon juvenilerearing guild. Reservoir areasbased on Chinook salmon fryreservoir rearing guild.Densityindependentsurvival rate0.8 AssumptionMortality due to predation andother sourcesAge O+ juvenileto age 1+ juvenileDensityindependentsurvival rate0.75 Lestelle et al. 1996 Over winter survivalSmithReservoirMigrantemergent fryfrom UpperSmithEmergent fry toresident fry (< 55mm)Migrant fry fromUpper SmithFry to 0+juveniles (> 55mm with no signsof smolting)Age O+ juvenileto age 1+ juvenileDensityindependentsurvival rate(duringmigration fromUpper Smith)Maximum frydensitySuitable habitatareaDensityindependentsurvival rateDensityindependentsurvival rate(duringmigration fromUpper Smith)Maximumjuvenile densityDensityindependentsurvival rateDensityindependentsurvival rate0.2511fish/100 m 2Fry seining data(Stillwater Sciences2006a)49,348 m 2 Habitat mapping(Stillwater Sciences2006b)0.8 Assumption0.2 Assumption220fish/100 m 20.5Piaskowski andTabor 2001Based on TrailBridge estimatesBased on estimates in CarmenBypass ReachCalculated densities based onshoreline beach seining in TrailBridge Reservoir. The threehighest values were 13, 126,and 511 fish/100m 2 .Estimated using Chinooksalmon fry rearing guild.Assume that survival ofemergent fry is low in thereservoir, but that the durationof time from emergent fry toresident fry is short.Conservative value for survival,based on estimates of frysurvival.Based on snorkel surveys innearshore habitat of southernLake Washington. Maximumdensity was observed in March,other densities reported by theauthors include 80, 160, and 15fish/100 m 2 during April, May,and June, respectively.0.75 Lestelle et al. 1996 Over winter survival28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-10

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportSub Reach Life-stage Parameter Value Source CommentsProportion usingFry Migration0.9Smith spillwayAssumes most fish will pass viafrom SmithAssumptionReservoirProportion usingSmith Spillway.0.1Smith intakeSmithBypassReach (viaspillpassage)Trail BridgeReservoir(via SmithIntake)Age 1+ juvenileto smolt (55–>100 mm)1+ juvenilemigrationSmolt migrationMaximumdensity forsmoltsSuitable habitatareaDensityindependentsurvival rateProportion usingSmith spillwayProportion usingSmith intakeProportion usingSmith spillwayProportion usingSmith intakeBradford (Dept. ofFish and Oceans, W.130 fish /100 m 2 VancouverLaboratory, pers.comm.)49,348 m 2 Habitat mapping(Stillwater Sciences2006b)0.8 Assumption0.90.10.90.1AssumptionAssumptionAll life-stages Passage survival 0.9 AssumptionSmolts leavingSmith BypassDensityindependentsurvival rate0.95 AssumptionAll life-stages Passage survival 0.05 AssumptionAssumed to be the same as forjuveniles. Assumes no smoltsrearing in river reaches.Assumed to be the same as forjuveniles. Assumes no smoltsrearing in river reaches.Assumes low mortality duringsmolting. Includes mortalityfrom stranding, entrainment,and predation.Assumes most fish will pass viaSmith Spillway.Assumes most fish will pass viaSmith Spillway.Passage mortality at spillway isnot known, but assumed to behigh relative to other spillwaysbased on it’s configuration.Assumes high survival ofsmolts passing through reach.Passage mortality at powertunnel and turbines is notknown, but assumed to be highbased on turbine type (Francistype).28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-11

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable E-7. Spring Chinook salmon population dynamics model parameters and values under currentconditions in the Carmen-Smith Spawning Channel.Life-stage Parameter Value SourceAdult (> 500 mm)to female spawnersFemale spawnerto depositedeggsDeposited eggs-toemergentfryEmergent fry toresident fry (< 55mm)Resident fry to 0+juveniles (> 55 mmwith no signs ofsmolting)Age O+ juvenile toage 1+ juvenileSex ratio(females tomales)Pre-spawningsurvivalSuitablespawning gravelareaNotes on model sensitivity,confidence, and certainty1:1.66 Smith 1993 Estimated in the Spawning Channel0.9Stillwater Sciences(2006a)2,000 m 2 Spawning Channeldimensions survey(Stillwater Sciences2006b)Mean redd area 5.4 m 2 of redd dimensions(Stillwater SciencesTotal station surveys2006a)Densityindependentrateof increase4,936Escape 5.1 submodelthis studySurvival rate 0.8 AssumptionMaximum frydensitySuitable habitatareaDensityindependentsurvival rateMaximumjuvenile densitySuitable habitatareaDensityindependentsurvival rateDensityindependentsurvival rate208 fish/100m 2 Bjorn (1978)562 m 2 Spawning Channeldimensions survey(Stillwater Sciences2006b)0.8 Assumption19.4 fish/100m 2Stillwater Sciences(2006a)562 m 2 Spawning Channeldimensions survey(Stillwater Sciences2006b)0.8 AssumptionBased on observations of adultChinook salmon and reddconstruction in Spawning Channelin 2004.Total estimated spawning channelarea is 2,800 m 2 . Estimate wasadjusted by subtracting areas whereno potential spawning habitat isavailable (e.g., holding pool)Assumed the same as CarmenBypass Reach.Based on Chinook salmonfecundity.Assumed to be high, because ofnew gravel in 2005.Big Springs Creek, Idaho (as citedin Smith et al. 1985). Densities of129 and 135 fish/ m 2 also reportedin Bjornn 1978 and Bjornn andReiser 1991, respectively.Assumes that margin areas aresuitable. Value is 20% of totalSpawning Channel surface area.Mortality due to predation andother sources.Based on snorkel observations,assuming 80% diver probability ofobservation. Less than maximumreported in literature (e.g., 30fish/100m 2 in Levings and Lauzier1991).Assumes that margin areas aresuitable. Value is 20% of totalspawning channel surface area.Mortality due to predation andother sources.0.75 Lestelle et al. 1996 Over winter survival28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-12

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportLife-stage Parameter Value SourceAge 1+ juvenile tosmolt (55–>100mm)Migrant emergentfry to smoltMigrant fry tosmoltMigrant juvenile tosmoltMaximumdensity forsmoltsSuitable habitatareaDensityindependentsurvival rateDensityindependentsurvival rate130 fish / 100m 2Bradford (Dept. ofFish and Oceans, W.VancouverLaboratory, pers.comm.)562 m 2 Spawning Channeldimensions survey(Stillwater Sciences2006b)0.8 Assumption0.010.070.65AssumptionNotes on model sensitivity,confidence, and certaintyAssumed to be the same as forjuveniles. Assumes no smoltsrearing in river reaches.Based on measurements in CarmenSmith Spawning Channel.Assumes low mortality duringsmolting.Based on sum of all mortality ratesestimated in the Trail Bridgepopulation. Includes mortality formigration from spawning channel,and mortality in the mainstemMcKenzie River from predation,and other sources. Assumes thathabitat is not limiting in themainstem. Objective is to provide anumber of smolts to compare toTrail Bridge Production, and is notconsidered precise. Mortality foremergent fry to smolts wasincreased to 99% to provide a moreconservative estimate forcomparisons.28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardE-13

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendix FSensitivity analysis for bull trout population dynamics modelTablesTable F-1. Results of bull trout model sensitivity analysis under current conditions (subadult/adultK=111)................................................................................................................................... F-1Table F-2. Sensitivity analysis with increase in subadult/adult carrying capacity (k=500)..................... F-5Copyright © 2006 Eugene Water & Electric Board - the following Appendix F to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report:Appendix FSensitivity analysis for bull trout population dynamics model

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable F-1. Results of bull trout model sensitivity analysis under current conditions (subadult/adult K=111).Life-step Parameter 50%decrease25%decreaseParameter valuesCurrent33%increase100%increase50%decreaseSteady-state adult population responses25%decreaseCurrent33%increaseProportion of females 0.25 0.375 0.5 0.6665 1 111 111 111 111 111Adults to female spawners Frequency of spawning (0to 1, i.e., annual=1)0.375 0.5625 0.75 0.9998 1.5 111 111 111 111 111Carmen Bypass Reach, Deposited Density-independenteggs-to-emergent frysurvival0.16 0.24 0.32 0.4266 0.64 111 111 111 111 111Suitable habitat area (m²) 465.5 698.25 931 1241 1862 111 111 111 111 111Carmen Bypass Reach, Emergent Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111fry to resident early fryDensity-independentsurvival0.5 0.75 1 1.333 2 111 111 111 111 111Suitable spawning gravelCarmen female spawners to area (m²)108 162 216 287.93 432 111 111 111 111 111deposited eggsMean redd area (m²) 0.91 1.365 1.82 2.4261 3.64 111 111 111 111 111Fecundity (#eggs/female) 1419.5 2129.3 2839 3784.4 5678 111 111 111 111 111Carmen Bypass Reach, 1+ Density-independentJuveniles to 2+ juvenilessurvival0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111Migration from Carmen to Density-independentreservoirsurvival0.45 0.675 0.9 1.1997 1.8 111 111 111 111 111Suitable habitat area (m²) 1040 1560 2080 2772.6 4160 111 111 111 111 111Carmen Bypass Reach, Resident Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111early fry to resident late fry Density-independent0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111survivalSuitable habitat area (m²) 2027 3040.5 4054 5404 8108 111 111 111 111 111Carmen Bypass Reach, Resident Density (fish/m²) 0.11 0.165 0.22 0.2933 0.44 111 111 111 111 111late fry to juvenilesDensity-independent0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111survivalReservoir, Emergent fry fromupstream to early fry grown inreservoirReservoir, 1+ Juveniles to 2+juveniles100%increaseSuitable habitat area (m²) 5244.5 7866.8 10489 13982 20978 111 111 111 111 111Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111Density-independentsurvival0.005 0.0075 0.01 0.0133 0.02 111 111 111 111 111Density-independentsurvival0.2 0.3 0.4 0.5332 0.8 111 111 111 111 11128 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-1

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responsesLife-step Parameter 50% 25%33% 100% 50% 25%33% 100%CurrentCurrentdecrease decreaseincrease increase decrease decreaseincrease increaseSuitable habitat area (m²) 123971 185956 247941 330505 495882 56 83 111 148 223Reservoir, Total juveniles to Density (fish/m²) 0.0002 0.0003 0.0004 0.0006 0.0009 56 83 111 148 223subadultsDensity-independent annual0.2 0.3 0.4 0.5332 0.8 111 111 111 111 111survivalSuitable habitat area (m²) 60591 90886 121181 161534 242362 111 111 111 111 111Reservoir, Total late fry to Density (fish/m²) 0.11 0.165 0.22 0.2933 0.44 111 111 111 111 111juveniles grown in reservoir Density-independent0.005 0.0075 0.01 0.0133 0.02 111 111 111 111 111survivalSuitable habitat area (m²) 5244.5 7866.8 10489 13982 20978 111 111 111 111 111Reservoir, Total early fry to late frygrown in reservoirReservoir, Migrant early fryleaving Carmen to early fry fromCarmenReservoir, Migrant early fryleaving Smith to early fry fromSmithReservoir, Migrant emergent fryleaving Sweetwater to emergent fryfrom SweetwaterReservoir, Migrant emergent fryleaving Carmen to emergent fryfrom CarmenReservoir, Migrant emergent fryleaving Smith to emergent fry fromSmithReservoir, Migrant emergent fryleaving Sweetwater to emergent fryfrom SweetwaterReservoir, Migrant late fry leavingCarmen to late fry from CarmenReservoir, Migrant late fry leavingSmith to late fry from SmithReservoir, Migrant late fry leavingSweetwater to late fry fromSweetwaterDensity (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111Density-independentsurvival0.025 0.0375 0.05 0.0667 0.1 111 111 111 111 111Density-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvival0.25 0.375 0.5 0.6665 1 111 111 111 111 1110.25 0.375 0.5 0.6665 1 111 111 111 111 1110.25 0.375 0.5 0.6665 1 111 111 111 111 1110.025 0.0375 0.05 0.0667 0.1 111 111 111 111 1110.025 0.0375 0.05 0.0667 0.1 111 111 111 111 1110.025 0.0375 0.05 0.0667 0.1 111 111 111 111 1110.45 0.675 0.9 1.1997 1.8 111 111 111 111 1110.45 0.675 0.9 1.1997 1.8 111 111 111 111 1110.45 0.675 0.9 1.1997 1.8 111 111 111 111 11128 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-2

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responsesLife-step Parameter 50% 25%33% 100% 50% 25%33% 100%CurrentCurrentdecrease decreaseincrease increase decrease decreaseincrease increaseReservoir, Previous adults to old Density-independentadults (>1 year at >400 mm FL) survival0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111Reservoir, Previous subadults to Density-independentnew adults (first year >400 mm FL) survival0.325 0.4875 0.65 0.8665 1.3 111 111 111 111 111Smith Bypass Reach, Deposited Density-independenteggs-to-emergent frysurvival0.27 0.405 0.54 0.7198 1.08 111 111 111 111 111Suitable habitat area (m²) 1698.5 2547.8 3397 4528.2 6794 111 111 111 111 111Smith Bypass Reach, Emergent fry Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111to resident early fryDensity-independent0.5 0.75 1 1.333 2 111 111 111 111 111survivalSuitable spawning gravelSmith female spawners toarea (m²)3.5 5.25 7 9.331 14 111 111 111 111 111deposited eggsMean redd area (m²) 0.91 1.365 1.82 2.4261 3.64 111 111 111 111 111Fecundity (#eggs/female) 1419.5 2129.3 2839 3784.4 5678 111 111 111 111 111Smith Bypass Reach, 1+ Juveniles Density-independentto 2+ juvenilessurvival0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111Migration from Smith to reservoirDensity-independentsurvival0.45 0.675 0.9 1.1997 1.8 111 111 111 111 111Suitable habitat area (m²) 4067.5 6101.3 8135 10844 16270 111 111 111 111 111Smith Bypass Reach, Resident Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111early fry to resident late fry Density-independent0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111survivalSuitable habitat area (m²) 3500 5250 7000 9331 14000 111 111 111 111 111Smith Bypass Reach, Resident Density (fish/m²) 0.11 0.165 0.22 0.2933 0.44 111 111 111 111 111early fry to resident late fry Density-independent0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111survivalSweetwater Creek, Deposited eggsto-emergentfrysurvivalDensity-independent0.05 0.075 0.1 0.1333 0.2 111 111 111 111 111Suitable habitat area (m²) 140.5 210.75 281 374.57 562 111 111 111 111 111Sweetwater Creek, Emergent fry to Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111resident early fryDensity-independent0.5 0.75 1 1.333 2 111 111 111 111 111survivalSuitable spawning gravelSweetwater female spawners to area (m²)81 121.5 162 215.95 324 111 111 111 111 111deposited eggsMean redd area (m²) 0.25 0.375 0.5 0.6665 1 111 111 111 111 111Fecundity (#eggs/female) 1419.5 2129.3 2839 3784.4 5678 111 111 111 111 11128 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-3

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responsesLife-step Parameter 50% 25%33% 100% 50% 25%33% 100%CurrentCurrentdecrease decreaseincrease increase decrease decreaseincrease increaseSweetwater Creek, 1+ Juveniles to Density-independent2+ juvenilessurvival0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111Migration from Sweetwater to Density-independentreservoirsurvival0.45 0.675 0.9 1.1997 1.8 111 111 111 111 111Suitable habitat area (m²) 440.5 660.75 881 1174.4 1762 111 111 111 111 111Sweetwater Creek, Resident early Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 111 111 111 111 111fry to resident late fryDensity-independent0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111survivalSuitable habitat area (m²) 1318.5 1977.8 2637 3515.1 5274 111 111 111 111 111Sweetwater Creek, Resident early Density (fish/m²) 0.11 0.165 0.22 0.2933 0.44 111 111 111 111 111fry to resident late fryDensity-independent0.4 0.6 0.8 1.0664 1.6 111 111 111 111 111survivalTotal female spawners to Carmen Proportion of spawners tospawnersCarmen0.37 0.555 0.74 0.9864 1.48 111 111 111 111 111Total female spawners to Smith Proportion of spawners tospawnersSmith R.0 0 0 0 0 111 111 111 111 111Total female spawners toProportion of spawners toSweetwater spawnersSweetwater Cr.0.13 0.195 0.26 0.3466 0.52 111 111 111 111 11128 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-4

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable F-2. Sensitivity analysis with increase in subadult/adult carrying capacity (K=500).Life-step Parameter 50%decrease25%decreaseParameter valuesCurrent33%increase100%increase50%decreaseSteady-state adult population responses25%decreaseCurrent33%increaseProportion of females 0.25 0.375 0.5 0.6665 1 500 500 500 500 500Adults to female spawners Frequency of spawning (0to 1, i.e., annual=1)0.375 0.5625 0.75 0.9998 1.5 500 500 500 500 500Carmen Bypass Reach, Deposited Density-independenteggs-to-emergent frysurvival0.16 0.24 0.32 0.4266 0.64 500 500 500 500 500Suitable habitat area (m²) 465.5 698.25 931 1241 1862 497.92 500 500 500 500Carmen Bypass Reach, Emergent Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 497.92 500 500 500 500fry to resident early fryDensity-independentsurvival0.5 0.75 1 1.333 2 500 500 500 500 500Suitable spawning gravelCarmen female spawners to area (m²)108 162 216 287.93 432 500 500 500 500 500deposited eggsMean redd area (m²) 0.91 1.365 1.82 2.4261 3.64 500 500 500 500 500Fecundity (#eggs/female) 1419.5 2129.3 2839 3784.4 5678 500 500 500 500 500Carmen Bypass Reach, 1+ Density-independentJuveniles to 2+ juvenilessurvival0.4 0.6 0.8 1.0664 1.6 497.92 500 500 500 500Migration from Carmen to Density-independentreservoirsurvival0.45 0.675 0.9 1.1997 1.8 497.92 500 500 500 500Suitable habitat area (m²) 1040 1560 2080 2772.6 4160 500 500 500 500 500Carmen Bypass Reach, Resident Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 500 500 500 500 500early fry to resident late fry Density-independentsurvival0.4 0.6 0.8 1.0664 1.6 497.92 500 500 500 500Suitable habitat area (m²) 2027 3040.5 4054 5404 8108 500 500 500 500 500Carmen Bypass Reach, Resident Density (fish/m²) 0.225 0.3375 0.45 0.5999 0.9 500 500 500 500 500late fry to juvenilesDensity-independentsurvival0.4 0.6 0.8 1.0664 1.6 497.92 500 500 500 500Suitable habitat area (m²) 5244.5 7866.8 10489 13982 20978 500 500 500 500 500Reservoir, Emergent fry fromupstream to early fry grown inDensity (fish/m²) 0.42 0.63 0.84 1.1197 1.68 500 500 500 500 500reservoirDensity-independent0.005 0.0075 0.01 0.0133 0.02 500 500 500 500 500survivalReservoir, 1+ Juveniles to 2+ Density-independentjuvenilessurvival0.2 0.3 0.4 0.5332 0.8 500 500 500 500 500100%increase28 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-5

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responsesLife-step Parameter 50% 25% Curren 33% 100% 50% 25%33% 100%Currentdecrease decrease t increase increase decrease decreaseincrease increaseSuitable habitat area (m²) 123971 185956 247941 330505 495882 382.35 382.35 500 569.99 569.99Reservoir, Total juveniles to Density (fish/m²) 0.001 0.0015 0.002 0.0027 0.004 382.35 382.35 500 569.99 569.99subadultsDensity-independent annual0.2 0.3 0.4 0.5332 0.8 476.17 500 500 500 500survivalSuitable habitat area (m²) 60591 90886 121181 161534 242362 500 500 500 500 500Reservoir, Total late fry to Density (fish/m²) 0.225 0.3375 0.45 0.5999 0.9 500 500 500 500 500juveniles grown in reservoir Density-independentsurvival0.005 0.0075 0.01 0.0133 0.02 500 500 500 500 500Suitable habitat area (m²) 5244.5 7866.8 10489 13982 20978 500 500 500 500 500Reservoir, Total early fry to late frygrown in reservoirDensity (fish/m²) 0.42 0.63 0.84 1.1197 1.68 500 500 500 500 500Reservoir, Migrant early fryleaving Carmen to early fry fromCarmenReservoir, Migrant early fryleaving Smith to early fry fromSmithReservoir, Migrant emergent fryleaving Sweetwater to emergent fryfrom SweetwaterReservoir, Migrant emergent fryleaving Carmen to emergent fryfrom CarmenReservoir, Migrant emergent fryleaving Smith to emergent fry fromSmithReservoir, Migrant emergent fryleaving Sweetwater to emergent fryfrom SweetwaterReservoir, Migrant late fry leavingCarmen to late fry from CarmenReservoir, Migrant late fry leavingSmith to late fry from SmithReservoir, Migrant late fry leavingSweetwater to late fry fromSweetwaterDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvivalDensity-independentsurvival0.025 0.0375 0.05 0.0667 0.1 500 500 500 500 5000.25 0.375 0.5 0.6665 1 500 500 500 500 5000.25 0.375 0.5 0.6665 1 500 500 500 500 5000.25 0.375 0.5 0.6665 1 500 500 500 500 5000.025 0.0375 0.05 0.0667 0.1 500 500 500 500 5000.025 0.0375 0.05 0.0667 0.1 500 500 500 500 5000.025 0.0375 0.05 0.0667 0.1 500 500 500 500 5000.45 0.675 0.9 1.1997 1.8 500 500 500 500 5000.45 0.675 0.9 1.1997 1.8 500 500 500 500 5000.45 0.675 0.9 1.1997 1.8 500 500 500 500 50028 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-6

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responsesLife-step Parameter 50% 25% Curren 33% 100% 50% 25%33% 100%Currentdecrease decrease t increase increase decrease decreaseincrease increaseReservoir, Previous adults to old Density-independentadults (>1 year at >400 mm FL) survival0.4 0.6 0.8 1.0664 1.6 417.05 493.52 500 500 500Reservoir, Previous subadults to Density-independentnew adults (first year >400 mm FL) survival0.325 0.4875 0.65 0.8665 1.3 500 500 500 500 500Smith Bypass Reach, Deposited Density-independenteggs-to-emergent frysurvival0.27 0.405 0.54 0.7198 1.08 500 500 500 500 500Smith Bypass Reach, Emergent fryto resident early frySmith female spawners todeposited eggsSmith Bypass Reach, 1+ Juvenilesto 2+ juvenilesMigration from Smith to reservoirSmith Bypass Reach, Residentearly fry to resident late frySmith Bypass Reach, Residentearly fry to resident late frySweetwater Creek, Deposited eggsto-emergentfrySweetwater Creek, Emergent fry toresident early frySweetwater female spawners todeposited eggsSuitable habitat area (m²) 1376.5 2064.8 2753 3669.7 5506 500 500 500 500 500Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 500 500 500 500 500Density-independentsurvival0.5 0.75 1 1.333 2 500 500 500 500 500Suitable spawning gravelarea (m²)3.5 5.25 7 9.331 14 500 500 500 500 500Mean redd area (m²) 0.91 1.365 1.82 2.4261 3.64 500 500 500 500 500Fecundity (#eggs/female) 1419.5 2129.3 2839 3784.4 5678 500 500 500 500 500Density-independentsurvival0.4 0.6 0.8 1.0664 1.6 500 500 500 500 500Density-independentsurvival0.45 0.675 0.9 1.1997 1.8 500 500 500 500 500Suitable habitat area (m²) 2282.5 3423.8 4565 6085.1 9130 500 500 500 500 500Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 500 500 500 500 500Density-independentsurvival0.4 0.6 0.8 1.0664 1.6 500 500 500 500 500Suitable habitat area (m²) 2825 4237.5 5650 7531.5 11300 500 500 500 500 500Density (fish/m²) 0.225 0.3375 0.45 0.5999 0.9 500 500 500 500 500Density-independentsurvival0.4 0.6 0.8 1.0664 1.6 500 500 500 500 500Density-independentsurvival0.05 0.075 0.1 0.1333 0.2 500 500 500 500 500Suitable habitat area (m²) 140.5 210.75 281 374.57 562 500 500 500 500 500Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 500 500 500 500 500Density-independentsurvival0.5 0.75 1 1.333 2 500 500 500 500 500Suitable spawning gravelarea (m²)81 121.5 162 215.95 324 500 500 500 500 500Mean redd area (m²) 0.25 0.375 0.5 0.6665 1 500 500 500 500 500Fecundity (#eggs/female) 1419.5 2129.3 2839 3784.4 5678 500 500 500 500 50028 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-7

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responsesLife-step Parameter 50% 25% Curren 33% 100% 50% 25%33% 100%Currentdecrease decrease t increase increase decrease decreaseincrease increaseSweetwater Creek, 1+ Juveniles to Density-independent2+ juvenilessurvival0.4 0.6 0.8 1.0664 1.6 500 500 500 500 500Migration from Sweetwater to Density-independentreservoirsurvival0.45 0.675 0.9 1.1997 1.8 500 500 500 500 500Suitable habitat area (m²) 440.5 660.75 881 1174.4 1762 500 500 500 500 500Sweetwater Creek, Resident early Density (fish/m²) 0.42 0.63 0.84 1.1197 1.68 500 500 500 500 500fry to resident late fryDensity-independentsurvival0.4 0.6 0.8 1.0664 1.6 500 500 500 500 500Suitable habitat area (m²) 1318.5 1977.8 2637 3515.1 5274 500 500 500 500 500Sweetwater Creek, Resident early Density (fish/m²) 0.225 0.3375 0.45 0.5999 0.9 500 500 500 500 500fry to resident late fryDensity-independentsurvival0.4 0.6 0.8 1.0664 1.6 500 500 500 500 500Total female spawners to Carmen Proportion of spawners tospawnersCarmen0.37 0.555 0.74 0.9864 1.48 500 500 500 500 500Total female spawners to Smith Proportion of spawners tospawnersSmith R.0 0 0 0 0 500 500 500 500 500Total female spawners toProportion of spawners toSweetwater spawnersSweetwater Cr.0.13 0.195 0.26 0.3466 0.52 500 500 500 500 50028 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardF-8

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportAppendix GSensitivity analysis for spring Chinook salmon populationdynamics modelTablesTable G-1. Sensitivity analysis for spring Chinook salmon under current conditions. .............. G-1Table G-2. Sensitivity analysis for spring Chinook salmon under current conditions in theCarmen-Smith Spawning Channel........................................................................... G-5Copyright © 2006 Eugene Water & Electric Board - the following Appendix G to the Population Dynamics of Bull Trout andSpring Chinook Salmon Technical Report:Appendix GSensitivity analysis for spring Chinook salmon populationdynamics model

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable G-1. Sensitivity analysis for spring Chinook salmon under current conditions.Life-step Parameter 50%decreaseAdults passed above Trail Bridge damto total female spawnersParameter valuesSteady-state adult population responses25%33% 100 50% 25%33% 100%CurrentCurrentdecreaseincrease increase decrease decreaseincrease increaseProportion of Females 0.25 0.375 0.5 0.6665 1 42.041 85.192 100.13 100.13 100.13Pre-spawning survival 0.25 0.375 0.5 0.6665 1 42.041 85.192 100.13 100.13 100.13Survival from smolt toreturning adult0.04 0.06 0.08 0.1066 0.16 21.021 63.894 100.13 133.47 200.25Passed smolts entering mainstem toadults returning to TB damSurvival during passage from fry inDownstream passageTrail Bridge Reservoir to mainstem.efficiencyEstimated based on Bell (1981)0.4 0.6 0.8 1.0664 1.6 100.13 100.13 100.13 100.13 100.13Survival during passage from juvenilesDownstream passagein Trail Bridge Reservoir to mainstem.efficiencyEstimated based on Bell (1981)0.4 0.6 0.8 1.0664 1.6 100.13 100.13 100.13 100.13 100.13Survival during passage from smolts inDownstream passageTrail Bridge Reservoir to mainstem.efficiencyEstimated based on Bell (1981)0.4 0.6 0.8 1.0664 1.6 21.021 63.894 100.13 125.16 125.16Carmen Bypass Reach, Deposited eggsto-emergentfryDensity-independent survival 0.16 0.24 0.32 0.4266 0.64 72.397 88.253 100.13 115.94 147.61Suitable habitat area (m²) 1040.5 1560.8 2081 2774 4162 97.321 98.723 100.13 101.99 105.74Carmen Bypass Reach, Emergent fry toresident fryDensity (fish/m²) 1.04 1.56 2.08 2.7726 4.16 97.321 98.723 100.13 101.99 105.74Density-independent survival 0.4 0.6 0.8 1.0664 1.6 72.397 88.253 100.13 112 112Suitable spawning gravel areaCarmen female spawners to deposited(m²)106 159 212 282.6 424 76.381 88.254 100.13 115.91 115.91eggsMean redd area (m²) 2.7 4.05 5.4 7.1982 10.8 115.91 115.91 100.13 88.262 76.381Fecundity (#eggs/female) 2468 3702 4936 6579.7 9872 72.397 88.254 100.13 115.94 147.61Suitable habitat area (m²) 2025 3037.5 4050 5398.7 8100 97.326 98.743 100.13 101.99 105.72Carmen Bypass Reach, Resident fry toDensity (fish/m²) 0.02 0.03 0.04 0.0533 0.08 97.326 98.743 100.13 101.99 105.720+ juvenilesDensity-independent survival 0.4 0.6 0.8 1.0664 1.6 92.647 96.386 100.13 103.86 103.86Carmen Bypass Reach, 0+ juveniles to1+ juveniles Density-independent survival0.375 0.5625 0.75 0.9998 1.5 96.976 98.551 100.13 102.22 102.23Returning adults to adults passed aboveTrail Bridge DamUpstream passage efficiency0.5 0.75 1 1.333 2 42.041 85.192 100.13 100.13 100.13Trail Bridge Reservoir, Emergent fryfrom upstream to fry grown in reservoirSuitable habitat area (m²) 5244.5 7866.8 10489 13982 20978 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 2.55 3.825 5.1 6.7983 10.2 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.25 0.375 0.5 0.6665 1 78.826 90.591 100.13 112.83 138.2728 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardG-1

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responses25%33% 100 50% 25%33% 100%CurrentCurrentdecreaseincrease increase decrease decreaseincrease increaseSuitable habitat area (m²) 5244.5 7866.8 10489 13982 20978 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 1.1 1.65 2.2 2.9326 4.4 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.25 0.375 0.5 0.6665 1 38.317 74.119 100.13 127.74 183.07Suitable habitat area (m²) 5244.5 7866.8 10489 13982 20978 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 1.1 1.65 2.2 2.9326 4.4 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.45 0.675 0.9 1.1997 1.8 21.021 63.894 100.13 111.25 111.25Life-step Parameter 50%decreaseTrail Bridge Reservoir, Total fry to 0+juveniles grown in reservoirTrail Bridge Reservoir, Total 1+juveniles to smolts grown in reservoirTrail Bridge Reservoir, Migrantemergent fry leaving Carmen toemergent fry from CarmenTrail Bridge Reservoir, Migrantemergent fry leaving Smith to emergentfry from SmithTrail Bridge Reservoir, Migrant fryleaving Carmen to fry from CarmenTrail Bridge Reservoir, Migrant fryleaving Smith to fry from SmithSmith Reservoir, Migrant fry leavingSmith Reservoir to migrant fry passedfrom Smith ReservoirSmith Bypass Reach, Migrant 1+juveniles leaving Smith Reservoir tomigrant 1+ juveniles passed from SmithReservoirSmith Bypass Reach, Smolts leavingSmith Reservoir to smolts passed fromSmith ReservoirSmith female spawners to Smith BypassspawnersSmith Bypass Reach, Deposited eggsto-emergentfrySmith Bypass Reach, Emergent fry toresident frySmith spawners to deposited eggsDensity-independent survival 0.1 0.15 0.2 0.2666 0.4 78.826 90.591 100.13 112.83 138.27Density-independent survival 0.1 0.15 0.2 0.2666 0.4 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.1 0.15 0.2 0.2666 0.4 92.997 96.561 100.13 104.87 114.38Density-independent survival 0.1 0.15 0.2 0.2666 0.4 82.282 92.49 100.13 110.3 130.67Downstream passageefficiencyDownstream passageefficiencyDownstream passageefficiencyProportion of Spawners toSmith Bypass0.1 0.15 0.2 0.2666 0.4 100.13 100.13 100.13 100.13 100.130.25 0.375 0.5 0.6665 1 100.13 100.13 100.13 100.13 100.130.25 0.375 0.5 0.6665 1 100.13 100.13 100.13 100.13 100.130.5 0.75 1 1.333 2 105.7 105.25 100.13 100.13 100.13Density-independent survival 0.27 0.405 0.54 0.7198 1.08 80.95 92.188 100.13 110.7 127.05Suitable habitat area (m²) 4067.5 6101.3 8135 10844 16270 99.183 100.13 100.13 100.13 100.13Density (fish/m²) 1.04 1.56 2.08 2.7726 4.16 99.183 100.13 100.13 100.13 100.13Density-independent survival 0.5 0.75 1 1.333 2 80.95 92.188 100.13 100.13 100.13Suitable spawning gravel area(m²)3.5 5.25 7 9.331 14 80.95 92.188 100.13 110.7 126.76Mean redd area (m²) 0.45 0.675 0.9 1.1997 1.8 126.76 110.71 100.13 92.194 80.95Fecundity (#eggs/female) 2468 3702 4936 6579.7 9872 80.95 92.188 100.13 110.7 129.9928 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardG-2

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responses25%33% 100 50% 25%33% 100%CurrentCurrentdecreaseincrease increase decrease decreaseincrease increaseSuitable habitat area (m²) 3500 5250 7000 9331 14000 95.287 97.706 100.13 103.34 109.8Density (fish/m²) 0.02 0.03 0.04 0.0533 0.08 95.287 97.706 100.13 103.34 109.8Density-independent survival 0.4 0.6 0.8 1.0664 1.6 80.95 92.188 100.13 108.06 108.06Suitable habitat area (m²) 24674 37011 49348 65781 98696 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 2.55 3.825 5.1 6.7983 10.2 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.1 0.15 0.2 0.2666 0.4 100.13 100.13 100.13 100.13 100.13Suitable habitat area (m²) 24674 37011 49348 65781 98696 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 1.1 1.65 2.2 2.9326 4.4 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.25 0.375 0.5 0.6665 1 100.13 100.13 100.13 100.13 100.13Life-step Parameter 50%decreaseSmith Bypass Reach, Total fry to 0+juvenilesSmith Reservoir, Emergent fry fromupstream to fry grown in reservoirSmith Reservoir, Total fry to 0+juveniles growin in reservoirSmith Reservoir, Juveniles and streamjuveniles to migrant juveniles en routeto Smith BypassSmith Reservoir, Juveniles and streamjuveniles to smolts grown in reservoirSmith Reservoir, Migrant emergent fryleaving Upper Smith to emergent fryfrom Upper SmithSmith Reservoir, Migrant fry leavingUpper Smith to fry from Upper SmithSmith Reservoir, 1+ juveniles leavingupper Smith to 1+ juveniles from upperSmithSmith Reservoir, Smolts to smolts enroute to Smith BypassSmith Reservoir, Total fry to migrantfry en route to Smith BypassSmith Reservoir, 0+ juveniles to 1+juvenilesSpawners to Smith Reservoir to UpperSmith spawnersSmith Bypass Reach, 0+ juveniles to 1+juvenilesTrail Bridge Reservoir, Migrant fryleaving Smith Reservoir to migrant frypassed from Smith ReservoirTrail Bridge Reservoir, 1+ juvenilesleaving Smith Reservoir to 1+ juvenilespassed from Smith ReservoirProportion of migrant juv. enroute to Smith Bypass0.45 0.675 0.9 1.1997 1.8 100.13 100.13 100.13 100.13 100.13Suitable habitat area (m²) 24674 37011 49348 65781 98696 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 1.1 1.65 2.2 2.9326 4.4 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.4 0.6 0.8 1.0664 1.6 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.1 0.15 0.2 0.2666 0.4 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.25 0.375 0.5 0.6665 1 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.45 0.675 0.9 1.1997 1.8 100.13 100.13 100.13 100.13 100.13Proportion of smolts en routeto Smith BypassProportion of migrant fry enroute to Smith Bypass0.45 0.675 0.9 1.1997 1.8 100.13 100.13 100.13 100.13 100.130.45 0.675 0.9 1.1997 1.8 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.375 0.5625 0.75 0.9998 1.5 100.13 100.13 100.13 100.13 100.13Pre-spawning survival 0.25 0.375 0.5 0.6665 1 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.375 0.5625 0.75 0.9998 1.5 94.682 97.404 100.13 103.75 103.75Downstream passageefficiencyDownstream passageefficiency0.025 0.0375 0.05 0.0667 0.1 100.13 100.13 100.13 100.13 100.130.025 0.0375 0.05 0.0667 0.1 100.13 100.13 100.13 100.13 100.1328 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardG-3

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportParameter valuesSteady-state adult population responsesLife-step Parameter 50% 25%33% 100 50% 25%33% 100%CurrentCurrentdecrease decreaseincrease increase decrease decreaseincrease increaseTrail Bridge Reservoir, 1+ juvenilesleaving Carmen Bypass to 1+ juveniles Density-independent survival 0.45 0.675 0.9 1.1997 1.8 96.976 98.551 100.13 100.83 100.83from Carmen BypassTrail Bridge Reservoir, 1+ juvenilesleaving Smith Bypass to 1+ juveniles Density-independent survival 0.45 0.675 0.9 1.1997 1.8 94.682 97.404 100.13 101.34 101.34from Smith BypassTrail Bridge Reservoir, Smolts leavingSmith Bypass Reach to smolts from Survival rate during migration 0.5 0.75 1 1.333 2 100.13 100.13 100.13 100.13 100.13Smith Bypass ReachTrail Bridge Reservoir, Smolts leavingDownstream passageSmith Reservoir to smolts passed fromefficiencySmith Reservoir0.025 0.0375 0.05 0.0667 0.1 100.13 100.13 100.13 100.13 100.13Trail Bridge Reservoir, 0+ juveniles to1+ juveniles grown in reservoirDensity-independent survival 0.375 0.5625 0.75 0.9998 1.5 38.317 74.119 100.13 127.74 127.77Total female spawners to Carmen Proportion of Spawners tofemale spawnersCarmen0.4 0.6 0.8 1.0664 1.6 72.397 89.126 100.13 35.284 35.284Upper Smith River, Deposited eggs-toemergentfryDensity-independent survival 0.25 0.375 0.5 0.6665 1 100.13 100.13 100.13 100.13 100.13Upper Smith River, Emergent fry toresident fryUpper Smith female spawners todeposited eggsUpper Smith River, Resident fry to 0+juvenilesUpper Smith River, 0+ juveniles to 1+juvenilesSuitable habitat area (m²) 306.5 459.75 613 817.13 1226 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 1.04 1.56 2.08 2.7726 4.16 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.4 0.6 0.8 1.0664 1.6 100.13 100.13 100.13 100.13 100.13Suitable spawning gravel area(m²)37.5 56.25 75 99.975 150 100.13 100.13 100.13 100.13 100.13Mean redd area (m²) 2.7 4.05 5.4 7.1982 10.8 100.13 100.13 100.13 100.13 100.13Fecundity (#eggs/female) 2468 3702 4936 6579.7 9872 100.13 100.13 100.13 100.13 100.13Suitable habitat area (m²) 791.5 1187.3 1583 2110.1 3166 100.13 100.13 100.13 100.13 100.13Density (fish/m²) 0.02 0.03 0.04 0.0533 0.08 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.4 0.6 0.8 1.0664 1.6 100.13 100.13 100.13 100.13 100.13Density-independent survival 0.375 0.5625 0.75 0.9998 1.5 100.13 100.13 100.13 100.13 100.1328 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardG-4

FINAL REPORT Carmen-Smith Hydroelectric Project (FERC No. 2242)Population Dynamics of Bull Trout and Spring Chinook Salmon Technical ReportTable G-2. Sensitivity analysis for spring Chinook salmon under current conditions in the Carmen-Smith Spawning Channel.Parameter valuesSteady-state adult population responsesLife-step Parameter 50% 25%33% 100 50% 25%33% 100%CurrentCurrentdecrease decreaseincrease increase decrease decreaseincrease increaseSpawning Channel, Smolts to returningadultsDensity-independent survival0.035 0.0525 0.07 0.0933 0.14 2.2634 3.3962 4.5287 6.0372 9.0584Spawning Channel, Adults to female Proportion of Females 0.25 0.375 0.5 0.6665 1 4.5268 4.5282 4.5287 4.529 4.5292spawnersPre-spawning survival 0.45 0.675 0.9 1.1997 1.8 4.5268 4.5282 4.5287 4.529 4.5292Spawning Channel, Deposited eggs-toemergentfryDensity-independent survival0.4 0.6 0.8 1.0664 1.6 4.5268 4.5282 4.5287 4.529 4.529Suitable habitat area (m²) 281 421.5 562 749.15 1124 4.4408 4.5055 4.5287 4.542 4.5515Spawning Channel, Emergent fry toDensity (fish/m²) 1.04 1.56 2.08 2.7726 4.16 4.4408 4.5055 4.5287 4.542 4.5515resident fryDensity-independent survival 0.5 0.75 1 1.333 2 4.5268 4.5282 4.5287 4.5287 4.5287Suitable spawning gravel areaSpawning Channel, Female spawners to(m²)1000 1500 2000 2666 4000 4.5287 4.5287 4.5287 4.5287 4.5287deposited eggsMean redd area (m²) 2.7 4.05 5.4 7.1982 10.8 4.5287 4.5287 4.5287 4.5287 4.5287Fecundity (#eggs/female) 2468 3702 4936 6579.7 9872 4.5268 4.5282 4.5287 4.529 4.5292Spawning Channel, 1+ juveniles tosmoltsSpawning Channel, Resident fry to 0+juvenilesSuitable habitat area (m²) 281 421.5 562 749.15 1124 4.4762 4.515 4.5287 4.5365 4.5421Density (fish/m²) 0.65 0.975 1.3 1.7329 2.6 4.4762 4.515 4.5287 4.5365 4.5421Density-independent survival 0.4 0.6 0.8 1.0664 1.6 2.2701 3.402 4.5287 5.6488 5.6488Suitable habitat area (m²) 281 421.5 562 749.15 1124 2.3034 3.4227 4.5287 5.9761 8.7833Density (fish/m²) 0.097 0.1455 0.194 0.2586 0.388 2.3034 3.4227 4.5287 5.9761 8.7833Density-independent survival 0.4 0.6 0.8 1.0664 1.6 4.4391 4.505 4.5287 4.5398 4.539828 March 2006 Stillwater SciencesCopyright © 2006 Eugene Water & Electric BoardG-5