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Workshop Participants . Panel Members & Chair . Presenters . Upper Basin _Tom Chart, USBR;Tom Czapla, U5FW5, Kevin Bestgen, Colorado State University, - Doug Osmundsen, USFWS . Grand Canyon ..Carl Walters, University of British Columbia; Lew Coggins, GCMRC Summary of Findings (see handout) 2. Are Upper Busin mel1mdB appropriate for use ill Ille Gmnd Canyon? . The ASMR is most appropriate for the Grand Canyon work because it takes advantage of spawning aggregations in the LCR and efficiently uses the extensive data collected over a longer period of sampling there. Work in the Upper Basin is limited by the shorter time series, less extensive sampling, and the consequent constraint on providing estimates of recruitment. mortality rates, and/or trend in abundance. Summary of Findings (see handout) J. Are then' ways ta improye me/hads used ;11 IIle Grand CanyolI ",ark? The Panel encourages consideration of telemetry approaches to address questions about migration to and from the LeR, use of simulation studies to evaluate potential biases ill ASMR population estimates, and recommends that results from well- established open population age-structured methods (Jolly-Seber models) be compared to results from the ASMR models. Similar analyses of Upper Basin closed model method9- will also be informative. , Participants Continued... . Discussion Participants . James Rice and William Pine, North Carolina State University . Observers . Randy Peterson, nOR; Steve Gloss, GCMRC . Summary of Findings (see handout) 2. Ar~ Upp~r /lflJln melhm/s ilpproprltd~ for us~ In th~ Gl1md c/lny<>"r . As more data become available in the Upper Basin studies, more complex models such as the ASMR can be applied. Upper Basin methods should llOt replace those c"rrentlv employed in the Gralld Canyon. There is 110 comDellinfl scientr:fic reasoIJ to chanrle the basic sDrin!! samolinl! schedule for Grand Canvonll..CR work to a fall schedule. Doinfl so mirIht create more Droblems than solut;ollS. Summary of Findings (see handout) 4. Do Orand Cmlyall methods proy/de rigoror/s data pertjn6llt to IlBC Recoyery GOllls? The ASMR method is appropriate for getting estimates of abundance, population growth rate (i.e., trend)~ and recruitment, if assumpJions about capture proDabilities are reasonable~ .Uoper Ba.~ill melhod.\' do not nrovide as much informatIOn a oul t ese t /fee CrlteTlll ecause 0 muc !lOwer caD ure rales...!n both. cases, th~-Pan.el recommends that emphasis be placed on estimates of population growth rate in determ.ining If a population is to be down-listed or de-hsted 2