IDAHO DEPARTMENT OF FISH AND GAME FISHERY MANAGEMENT ANNUAL REPORT Virgil Moore, Director UPPER SNAKE REGION 2013 Brett High Regional Fisheries Biologist Dan Garren Regional Fisheries Manager Greg Schoby Regional Fisheries Biologist Jessica Buelow Regional Fisheries Biologist August 2015 IDFG 15-108 i 2013 Upper Snake Region Annual Fisheries Management Report Table of Contents LAKES AND RESERVOIRS HENRYS LAKE ABSTRACT ............................................................................................................................ 1 OBJECTIVES ......................................................................................................................... 2 METHODS ............................................................................................................................. 2 Population Monitoring .......................................................................................................... 2 Creel Survey ....................................................................................................................... 3 Water Quality ...................................................................................................................... 4 RESULTS .............................................................................................................................. 4 Population Monitoring .......................................................................................................... 4 Creel Survey ....................................................................................................................... 5 Water Quality ...................................................................................................................... 5 DISCUSSION ......................................................................................................................... 5 MANAGEMENT RECOMMENDATIONS ................................................................................ 6 ISLAND PARK RESERVOIR ABSTRACT ...........................................................................................................................22 OBJECTIVES ........................................................................................................................23 METHODS ............................................................................................................................23 RESULTS .............................................................................................................................23 DISCUSSION ........................................................................................................................24 RIRIE RESERVOIR ABSTRACT ...........................................................................................................................34 INTRODUCTION ...................................................................................................................35 OBJECTIVES ........................................................................................................................36 METHODS ............................................................................................................................36 RESULTS .............................................................................................................................36 DISCUSSION ........................................................................................................................37 MANAGEMENT RECOMMENDATIONS ...............................................................................38 MACKAY RESERVOIR ABSTRACT ...........................................................................................................................52 METHODS ............................................................................................................................53 RESULTS .............................................................................................................................53 DISCUSSION ........................................................................................................................53 MANAGEMENT RECOMMENDATIONS ...............................................................................54 RIVERS AND STREAMS SOUTH FORK SNAKE RIVER ABSTRACT ...........................................................................................................................60 INTRODUCTION ...................................................................................................................61 METHODS ............................................................................................................................61 ii Table of Contents - cont. Radio Telemetry ................................................................................................................ 61 RESULTS .............................................................................................................................63 South Fork Population Monitoring ..................................................................................... 63 Weirs ................................................................................................................................. 63 Radio Telemetry ................................................................................................................ 64 Spring Flows ..................................................................................................................... 64 South Fork Angler Incentive Program ................................................................................ 65 PIT tags ............................................................................................................................. 65 RBT Removals .................................................................................................................. 65 DISCUSSION ........................................................................................................................66 South Fork Population Monitoring ..................................................................................... 66 Weirs ................................................................................................................................. 67 Radio Telemetry ................................................................................................................ 68 Spring Flows ..................................................................................................................... 69 South Fork Angler Incentive Study .................................................................................... 69 PIT tags ............................................................................................................................. 70 SNAKE RIVER ABSTRACT ...........................................................................................................................80 INTRODUCTION ...................................................................................................................81 STUDY SITE .........................................................................................................................81 OBJECTIVES ........................................................................................................................82 METHODS ............................................................................................................................82 RESULTS .............................................................................................................................83 DISCUSSION ........................................................................................................................84 MANAGEMENT RECOMMENDATIONS ...............................................................................86 TETON RIVER ..........................................................................................................................95 ABSTRACT ...........................................................................................................................95 INTRODUCTION ...................................................................................................................96 OBJECTIVES ........................................................................................................................96 METHODS ............................................................................................................................96 RESULTS .............................................................................................................................96 DISCUSSION ........................................................................................................................97 HENRYS FORK ...................................................................................................................... 116 ABSTRACT ......................................................................................................................... 116 STUDY SITE ....................................................................................................................... 117 OBJECTIVES ...................................................................................................................... 117 METHODS .......................................................................................................................... 117 RESULTS ..........................................................................................................................