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Green River Juvenile Salmonid Production Evaluation: 2009-2010 Annual Report

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Green River Juvenile Salmonid Production Evaluation: 2009-2010 Annual Report STATE OF WASHINGTON January 2011 Green River Juvenile Salmonid Production Evaluation: 2009-2010 Annual Report by Pete Topping, and Mara Zimmerman Washington Department of Fish and Wildlife Fish Program Science Division FPA 11-01 Green River Juvenile Salmonid Production Evaluation: 2009 and 2010 Annual Report Pete Topping Mara Zimmerman Washington Department of Fish and Wildlife Fish Program, Science Division January 2011 Acknowledgements Measuring juvenile salmon production from large river systems like the Green River involves a tremendous amount of work. Developing these estimates was possible due to the long hours of trap operation provided by our dedicated scientific technicians: Bob Green, Josh Weinheimer, Matt Pollack, Jeff Loveland and Paul Lorenz. Logistical support was provided by Wild Salmon Production Evaluation Unit biologist Mike Ackley. A number of other individuals and agencies contributed to this project. Bill Mosby, the adjacent landowner, provided access to the trap site. Mike Wilson, manager of the WDFW Soos Creek hatchery, provided logistical support and a secure staging site near the trap. Steve Foley and Darcy Wildermuth, WDFW Region 4, provided Chinook spawner survey data. The juvenile salmonid production study on the Green River was initiated in 2000. This study was funded by the Washington State legislature between 2000 and 2002, by the Washington Salmon Recovery Funding Board (SRFB) between 2002 and 2007, and by Tacoma Public Utilities, Water Division between 2008 and 2010. Green River Juvenile Salmonid Production Evaluation: 2009 and 2010 Annual Report i Green River Juvenile Salmonid Production Evaluation: 2009 and 2010 Annual Report ii Table of Contents ACKNOWLEDGEMENTS ............................................................................................................. I TABLE OF CONTENTS .............................................................................................................. III LIST OF TABLES ........................................................................................................................ V LIST OF FIGURES .................................................................................................................... VII EXECUTIVE SUMMARY ............................................................................................................. 1 INTRODUCTION ....................................................................................................................... 3 OBJECTIVES ..................................................................................................................................... 4 METHODS ................................................................................................................................ 5 TRAP OPERATION ............................................................................................................................. 5 FISH COLLECTION ............................................................................................................................. 5 FRESHWATER PRODUCTION ESTIMATE .................................................................................................. 6 FRESHWATER LIFE HISTORY DIVERSITY FOR CHINOOK SALMON .................................................................. 8 EGG‐TO‐MIGRANT SURVIVAL FOR SUB YEARLING CHINOOK...................................................................... 9 BASIN‐WIDE ABUNDANCE OF SUB YEARLING CHINOOK ............................................................................ 9 2009 RESULTS ........................................................................................................................ 11 SUB YEARLING CHINOOK ................................................................................................................. 11 YEARLING CHINOOK ........................................................................................................................ 13 COHO .......................................................................................................................................... 13 STEELHEAD ................................................................................................................................... 15 CHUM .......................................................................................................................................... 16 OTHER SPECIES .............................................................................................................................. 17 2010 RESULTS ........................................................................................................................ 19 SUB YEARLING CHINOOK ................................................................................................................. 19 YEARLING CHINOOK ........................................................................................................................ 21 COHO .......................................................................................................................................... 21 STEELHEAD ................................................................................................................................... 23 CHUM .......................................................................................................................................... 24 PINKS........................................................................................................................................... 25 OTHER SPECIES .............................................................................................................................. 26 DISCUSSION AND SYNTHESIS ................................................................................................. 27 ASSUMPTIONS FOR MARK‐RECAPTURE ESTIMATES ............................................................................... 27 ASSUMPTION FOR MISSED CATCH ..................................................................................................... 30 SUB YEARLING CHINOOK ................................................................................................................. 31 PINKS........................................................................................................................................... 36 YEARLING MIGRANTS ...................................................................................................................... 38 Green River Juvenile Salmonid Production Evaluation: 2009 and 2010 Annual Report iii SUMMARY .................................................................................................................................... 39 APPENDIX A ........................................................................................................................... 41 APPENDIX B ........................................................................................................................... 45 APPENDIX C ........................................................................................................................... 51 APPENDIX D ........................................................................................................................... 55 APPENDIX E ........................................................................................................................... 61 APPENDIX F ........................................................................................................................... 65 APPENDIX G ........................................................................................................................... 69 APPENDIX H ........................................................................................................................... 77 APPENDIX I ............................................................................................................................ 81 APPENDIX J ............................................................................................................................ 87 APPENDIX K ........................................................................................................................... 91 REFERENCES .......................................................................................................................... 96 Green River Juvenile Salmonid Production Evaluation: 2009 and 2010 Annual Report iv List of Tables TABLE 1.─CATCH AND PRODUCTION (ABUNDANCE) ESTIMATES FOR JUVENILE SALMONIDS LEAVING THE GREEN RIVER IN 2009 AND 2010 __________________________________________________________ 1 TABLE 2.─CATCH, MARKED AND RECAPTURED FISH, AND ESTIMATED ABUNDANCE OF SUB YEARLING CHINOOK MIGRANTS AT THE GREEN RIVER SCREW TRAP IN 2009. ______________________________________ 11 TABLE 3.─CATCH, MARKED AND RECAPTURED FISH, AND ESTIMATED ABUNDANCE OF NATURAL‐ORIGIN COHO SMOLTS AT THE GREEN RIVER SCREW TRAP IN 2009. _______________________________________ 13 TABLE 4.─CATCH, MARKED AND RECAPTURED FISH, AND ABUNDANCE ESTIMATE FOR STEELHEAD SMOLTS REARING ABOVE THE GREEN RIVER SCREW TRAP IN 2009. __________________________________________ 15 TABLE 5.─CATCH, MARKED AND RECAPTURED FISH, AND ESTIMATED ABUNDANCE OF SUB YEARLING CHINOOK MIGRANTS AT THE GREEN RIVER SCREW TRAP IN 2010. ______________________________________ 19 TABLE 6.─ CATCH, MARKED AND RECAPTURED FISH, AND ESTIMATED ABUNDANCE OF NATURAL‐ORIGIN COHO SMOLTS AT THE GREEN RIVER SCREW TRAP IN 2010. _______________________________________
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