Recovery Plan for the Northern Spotted Owl - DRAFT

lowlands, eastern Oregon Cascades, eastern California Cascades - currentlycannot support demographic studies equivalent to those found in the otherprovinces because of low owl numbers. Density and demographic studiescould be initiated in these provinces when their owl populations have increasedto the point that delisting can be considered.General recommendations for demographic studies are as follows:1. Maintain existing demographic study areas. Since owls are long-livedanimals, long duration population studies will be necessary to estimatepopulation trends. Assessment of annual changes in vital rates is necessaryto draw appropriate inferences from the study. The most cost-effectiveway to evaluate owl populations is to continue the demographic studies.The longer a study has existed the more valuable it is for assessing trendsin demography.2. Expand demographic study areas to include larger areas that will encompassowls within several DCAs and the province matrix. This will allowsome estimation of immigration into DCAs. While this will not allow anabsolute estimate of the number of immigrants, it will provide evidencethat immigration is occurring and it will provide estimates of the sources ofthe immigrants and distances traveled. Such large study areas encompassingthe demography study areas also would improve the analysis ofregional trends in demography.3. Monitor demographic trends in both the matrix and the DCA networkwithin each province. Franklin and Gutierrez (unpub. data) indicate thatindividual owl pairs monitored throughout the California Kiamath provincehave the same (i.e., not statistically different) vital rates as a population ofcontiguous owls in the Willow Creek demographic study area. The cost forthis monitoring is minimal and could be conducted in conjunction with thecurrent demographic studies (Appendix A).Owl population trends. Numerical trends of owls should be monitored in thematrix and DCA network within each province. Several methods have beendeveloped to estimate numerical and density estimates for owls includingtransect sampling (Forsman et al. 1977), capture-recapture models, empiricalestimation, quadrat sampling (Franklin et al. 1990b), and catch per unit effortmodels (Ward et al. 1991). Additional sampling procedures are presented inAppendix A.Population Modeling. Mathematical modeling is a powerful tool for assessingpopulation dynamics. The Recovery Team recommends that the developmentof models, such as those produced by scientists at the Forest Service RedwoodSciences Laboratory, continue.CoordinationThe monitoring and research effort must be coordinated among the responsiblefederal agencies and state agencies, and private interests, including universities.This coordination should be part of the function of the coordinating groupestablished during the implementation of this plan (see section III.C.5). Thecoordinating group will help ensure that all required parts of the monitoringprogram are conducted; that monitoring designs are coordinated amongagencies and landowners: that the monitoring proceeds according to design;that monitoring reports are prepared and reviewed on an established schedule;that periodic reviews are made to see if management adjustments are neededor desirable: and that recommended research activities are coordinated amongagencies so that research is efficient and representative of the entire range ofthe subspecies.208