1992 Annual Report
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THE OREGON PLAN for Salmon and Watersheds Status of Oregon Coastal Stocks of Anadromous Salmonids, 2000-2001 and 2001-2002 Report Number: OPSW-ODFW-2002-3 Status of Oregon Coastal Stocks of Anadromous Salmonids, 2000-2001 and 2001-2002 Oregon Plan for Salmon and Watersheds Monitoring Report No. OPSW-ODFW-2002-3 September, 2002 Steven Jacobs Julie Firman Gary Susac David Stewart Jared Weybright Coastal Salmonid Inventory Project Western Oregon Research and Monitoring Program Oregon Department of Fish and Wildlife 28655 Highway 34 Corvallis, OR 97333 Funds supplied in part by: Sport Fish and Wildlife Restoration Program administered by the U.S. Fish and Wildlife Service, Anadromous Fisheries Act administered by the National Marine Fisheries Service, Pacific Salmon Treaty administered by the National Marine Fisheries Service, and State of Oregon (General and Wildlife Funds). Citation: Jacobs S., J. Firman, G. Susac, D. Stewart and J. Weybright 2002. Status of Oregon coastal stocks of anadromous salmonids, 2000-2001 and 2001-2002; Monitoring Program Report Number OPSW-ODFW-2002-3, Oregon Department of Fish and Wildlife, Portland, Oregon. CONTENTS EXECUTIVE SUMMARY..................................................................................1 Fall Chinook ............................................................................................................................1 Coho ........................................................................................................................................2 Chum .......................................................................................................................................3 Steelhead.................................................................................................................................3 INTRODUCTION .....................................................................................................4 SURVEY PROGRAM DESIGN .................................................................................................4 SURVEY PROCEDURE ...........................................................................................................5 ASSESSMENT OF SURVEY CONDITIONS.............................................................................7 CHAPTER 1: FALL CHINOOK SALMON .......................................9 CURRENT MONITORING PROGRAM.....................................................................................9 ASSESSMENT UNITS............................................................................................................10 METHODS..............................................................................................................................12 Survey Design .......................................................................................................................12 Measures of Spawning Escapement ...................................................................................12 RESULTS AND DISCUSSION................................................................................................16 Assessment of Survey Conditions ......................................................................................16 Spawning Timing ..................................................................................................................16 Index of Spawner Abundance..............................................................................................18 Occurrence of Hatchery Fish in Natural Spawning Areas .................................................19 Trends in Spawner Abundance............................................................................................21 ESUs...................................................................................................................................21 GCAs ..................................................................................................................................23 ii CHAPTER 2: COHO SALMON................................................................26 CURRENT MONITORING PROGRAM...................................................................................26 ASSESSMENT UNITS............................................................................................................27 METHODS..............................................................................................................................29 Measures of Spawning Escapement ...................................................................................29 Estimates of Coho Salmon Spawner Population Abundance ...........................................31 Oregon Coastal ESU...........................................................................................................31 South Coast ESU ................................................................................................................35 RESULTS AND DISCUSSION................................................................................................36 Assessment of Survey Conditions ......................................................................................36 Spawning Timing ..................................................................................................................37 Measures of Spawner Abundance.......................................................................................39 Peak Counts and AUCs.......................................................................................................39 Trends in Spawner Abundance............................................................................................41 Spawner Distribution............................................................................................................46 Estimates of Spawner Abundance ......................................................................................50 EMAP Estimates for 2000 and 2001....................................................................................50 Relationship between Standard and Random Surveys........................................................54 Coastal Lake Basins............................................................................................................55 Oregon Coastal ESU...........................................................................................................57 Southern Oregon ESU ........................................................................................................58 Occurrence of Hatchery Fish in Natural Spawning Areas .................................................61 Observations of Fin Marks on Live and Dead Fish ..............................................................64 CHAPTER 3: CHUM SALMON................................................................67 CURRENT MONITORING PROGRAM...................................................................................67 ASSESSMENT UNITS............................................................................................................67 METHODS..............................................................................................................................68 Survey Design .......................................................................................................................68 Measures of Spawning Escapement ...................................................................................68 iii RESULTS AND DISCUSSION................................................................................................68 Assessment of Survey Conditions ......................................................................................68 Spawning Timing ..................................................................................................................69 Index of Spawning Abundance ............................................................................................69 Trends of Spawner Abundance ...........................................................................................72 Standard Surveys................................................................................................................72 Supplemental Surveys.........................................................................................................72 CHAPTER 4: STEELHEAD.........................................................................76 CURRENT MONITORING PROGRAM...................................................................................76 ASSESSMENT UNITS............................................................................................................76 STUDY OBJECTIVES ............................................................................................................77 METHODS..............................................................................................................................78 Objective 1 Results (Survey Feasibility)..............................................................................78 Task 1.1 (Selection of Spawning Surveys) .........................................................................78 Task 1.2 (Survey Feasibility) ..............................................................................................78 Task 1.3 (Distinction of Redds) ..........................................................................................78 Task 1.3 (Redd Longevity and Survey Recurrence Interval)...............................................78 Task 1.4 (Spawning Timing)................................................................................................79