Long-term Studies of Macroinvertebrate Responses to Harvest

Differences betweenStudy WatershedsSiteCharacteristicsHinkle Trask Alsea# invertebrate 24 16 6sitesWS area(sq. km)Geology0.21—10.57Basalt0.26—6.68Mixed0.26—1.67SandstoneElevation (m) 448—695 324—729 135—222Percent slope 3.9—21.5 2.7—18.8 2.5—6.0Avg. Annualprecip (in)Aug avg dailymax tempJan avg dailymin temp81.1 121.7 84.827.5 0 C 24.6 0 C 25.0 0 C1.1 0 C 0.4 0 C 2.3 0 C

SiteCharacteristicsHinkle Trask Alsea# invertebratesitesWS area(sq. km)Geology24 16 6largestBasaltMixedElevation (m) Greatest range,Percent slopeSome sitessteepesthighestSimilar to HinklesmallTyeeSandstonelowestLeastgradientAvg. Annualprecip (in)least greatest Similar toHinkleAug avg dailymax tempJan avg dailymin temp27.5 0 C 24.6 0 Cwarmest cooler1.1 0 C 0.4 0 Ccoldest25.0 0 C2.3 0 Cwarmest

How do patterns of benthic invertebratesin these watersheds compare?How will they respond to harvest?

Characteristics of Stream Invertebrates1. High Variation in Densities & CompositionSamples with many taxa2. Variation in Life Histories3. Variation in SensitivitiesLocal Longevity v. ColonizersTolerant v.s. Sensitive

Using Diversity & Variation in Study DesignEvaluating:AbundanceCompositionLife HistoriesSensitivitiesDensities, BiomassTaxa at each site (Taxa richness)Relative abundances of taxaEmergence of adultsProportions of tolerant taxa(Chironomids)

WRC Sites Study ApproachControl, Unlogged v. Logged SitesBefore and After HarvestTrask : 4 sub‐basins1 control/subasin7 treated headwaters4 mainstemAlsea: 1 control tributary1 upstream logged trib2 yrs postharvestHinkle: 7 North Fk control : 3 headwater + 1, 3 mainstem10 South Fk treated: 4 headwater, (3 dwnstm tribs), 6 mainstem4 yrs after headwater harvest, 1 yr post‐mainstem harvest

HinkleSeasonal & Annual Variation in Benthic DensitiesBenthic invertebrates per square meter(log scale)3000030003002004 2006springsummerfallUnlogged Hinkle headwaters

A Comparison of Spring Benthic Samples, Unlogged SitesDistinctive Invertebrate Assemblages at Each Watershed(NMS Ordination; each symbol = collection at one site)WS_Year0.5JugaPristinicolaHinkle 2007Hinkle 2008Alsea 2007Alsea 2008Trask 20072sixA-0.5ParaleptophlebiaTanypodinaeAcariLepidostomaOptioservus / HeterlimniusAmeletusEpeorusIronodesRhyacophilaBaetis-1.5-1.5-0.5 0.5 1.5Axis 1

Benthic densities at Hinkle headwaters were lowerMore variable at Trask2007 2008 2009 2007 2008 2009 2007 2009Hinkle no‐log Alsea Traskpreharvest preharvest

Among Non‐Rare Invertebrates (≥ 1% at a Site)Few Found In Common at All 3 WRC watershedsBenthics:3 Mayflies1 Stonefly1 Chironomid tribeOligochaete (worms)Emergent Adults:3 Mayflies3 Caddisflies

Differences between Headwaters and Mainstemsat Hinkle & Trask (preharvest):Density, Percent Chironomidae & Taxa CompositionNMS Summer Trask 2006‐10HeadwaterDownstreamAxis 3(R 2 =0.209)TanypodinaeOstracodaDrunellaBaetisMalenka, Epeorus, RhyacophilaCinygmulaYoraperlaAxis 1 (R 2 =0.428)

)Assessing Effects of HarvestHinkle Creek2005 in TributariesNorth Fork: 4 Control reachesSouth Fork: 4 Headwaters harvested2008 Harvest in MainstemNorth Fork: 3 Control reachesSouth Fork: 6 Harvested reaches

Hinkle: Effects of Harvest on Taxa Composition1.5harvestharvestednot harvestedBaetis0.5EpeorusAxis 3OrthocladiinaeVisokaCinygmulaSweltsa/Alloperla‐0.5‐1.5NematodaTanypodinaePisidiidaeOligochaetaPristinicola‐2.0‐1.0 0.0 1.0Axis 1

Invertebrate Responsein Hinkle Headwaters:Densities IncreasedBenthic invertebrates per square meter300003000300Preharvest:No difference2004 2005 2006 2007 2008 2009headwaterloggingcontroltreatment

Invertebrate Response in Hinkle Headwaters:Percent Chironomids Increased,Taxa Richness DecreasedBenthic percentchironomids10010controltreatmentBenthic taxa richness1555045403530252004 2005 2006 2007 2008 2009controltreatment2004 2005 2006 2007 2008 2009headwaterlogging

Benthic invertebrates per square meter300003000300Hinkle Tributaries with Fish:No downstream effects on invertebratesafter harvest in headwaters2004 2005 2006 2007 2008 2009controltreatmentBenthic densities (in this graph), percent chironomids andtaxa richness did not differ significantly from controls

Hinkle Mainstem Invertebrate Responses:Percent Chironomids Increased100Benthic percentchironomids10controltreatment12004 2005 2006 2007 2008 2009Benthic taxa richness5550454035Taxa Richness Decreasedcontroltreatment30252004 2005 2006 2007 2008 2009

Fish at Hinkle Mainstem:Diet responded to Increase in chironomids80Benthic percentchironomids6040200100Fish gut contentpercent chironomids8060402002004 2005 2006 2007 2008 2009headwaterloggingMS logging& dam-break flood

Mainstem Responses:Benthic Densities DID NOT IncreaseBenthic invertebrates per square meter3000030003002004 2005 2006 2007 2008 2009controltreatmentheadwaterloggingMS logging anddam‐break flood

South Fork Hinkle: No Detected Change in Benthic DensityMay be Explained by Increase in Fish Biomass

Invertebrate Mainstem Responses:Adult Aquatic Emergence IncreasedAquatic insect emergence ratenumber/square meter/day1001012005 2006 2007 2008 2009controltreatmentheadwaterloggingMS logging anddam‐break flood

60Hinkle & Alsea Aquatic Emergence 2009Higher Emergence at Logged SitesIndividuals/m 2 /day50403020100Hinkle Unlogged Hinkle Logged Flynn Needle Branch

Alsea: Few detectable differences postharvest at NeedlebranchHigh variation between sites, fewer replicatesBenthic invertebrates per square meter(log scale)3000030003002007 2008 2009 2010 2011FlynnNeedlebranchheadwaterlogging

Alsea: Cutthroat diet after harvestAverage fish diet composition100%80%60%40%20%unknownterrestrialsadult aquaticsaquatics0%Flynn NB Flynn NB2007 ‐ 2009 2010 ‐ 2011

Trask: Seasonal & Annual Variation in EmergenceDetecting Changes in Life HistoriesEmergence of Aquatic Insects Trask 2008‐2010Individuals/m2/day504540353025201510506/26 7/6 7/16 7/26 8/5 8/15 8/25 9/4200820092010

Trask: Measuring Benthic BiomassContributions to Stream Productivity1.6Trask Biomass 2009‐20111.41.2HeadwaterDownstreamBenthic Biomass (g)/m2Mean + S.E.10.80.60.40.20April June Aug/Sept

WRC Sites Study Designs:Key to Detecting DifferencesAlsea: limited samplesMore years,WRC context importantTrask : Controls within sub‐basinExpanded measurementslife histories, productivityHinkle: High replication in space & timeSignificant differences adjacent to harvestCoordinated sampling suggest connections to fish consumption

Field and lab assistants:Thanks to manyLinda Ashkenas, Jenny Ruthven, Jenn King, PhilBrown, Anthony Olegario, Katie Whitehead, PeteOber, Lance Wyss, Jeremy Romer, Julie House,Kylie Meyer, Scott Bartle, Chrissy Murphy,Amanda Robillard, Randy Colvin, Lucas Cramer,Asako Yamamuro and others…Fish friends:Dave Leer, Steve Clark and the fish crewsStatistics consultation:Lisa GanioFunding:OSU Forest Research Lab—Fish and Wildlife Habitatin Managed Forests Research ProgramOregon Department of Forestry; Weyerhauser;Roseburg Forest Products, Plum Creek; USGS

FlynnAlsea WatershedNeedle BranchPreharvest study: 2007‐2009Small tributaries with fishFlynn Creek3 reachesno harvestNeedlebranch3 reachesHarvest in 2009upstream ofstudy reaches

Upper Trask Watershed4 Subbasins, 3 ownerships2006‐2011 Preharvest SamplingHarvest 2012 in modified plan11 Headwater 4 Mainstem Reaches