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This study analyzes the catch rates and aggression levels of summer steelhead in the Deschutes River, Oregon, from 1977 to 2011. It explores the reasons why hatchery fish may not bite and compares the catch rates of wild and hatchery steelhead. The study also raises questions about the effects of catch and release mortality rates and the implications for brood stock selection.
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Examination of Angler Catch by Stock Composition of Summer Steelhead in the Deschutes River, Oregon, 1977 to 2011. Why Don’t Hatchery Fish Bite? Jason Seals Mid-Columbia Fish District Oregon Department of Fish and Wildlife
Population Monitoring Creel Catchability of Hatchery and Wild FISH AGGRESSION!! ???
Ladder/Steeppass Trap 2,000-3,000 StS June to End of October First Marking Event M-R SHERARS FALLS TRAP
CREEL METHODS1977-2012 • Expandable Collection Procedure • Stratified Collection Period • Weekdays and Weekends • Expansion Rate not to Exceed 3.0 • Number of Anglers, Angler Hours and Catch are Expanded
ANGLER DAYS --------------------------------------------------------------------------------------------------------------------------------------
In the Deschutes: Wild Steelhead were Caught by Anglers at Higher Rates, Even Though Hatchery Steelhead were Present at Substantially Higher Numbers SUMMARY
Are Wild Steelhead More Aggressive? Is this unique to the Deschutes? During years of very low abundance of wild fish, are catch and release risks increased? MANAGEMENT QUESTIONS
How does this effect assumed catch and release mortality rates? Should we consider this information when determining brood stock take? MANAGEMENT QUESTIONS