The effects of summer flow augmentation on the migratory behavior and survival of juvenile Snake River fall Chinook salmon Project

Overview of Summer Flow Augmentation

Objective 1) Provide information to fishery managers to maximize the effectiveness of summer flow augmentation PIT Tagging Studies

In-season Analyses

In season analyses NAJFM (20: )

Pursuant to 28 U.S.C. § 1746, I declare under the penalty of perjury that the foregoing is true and correct to the best of my knowledge, based on my education, experience and professional judgment. Executed July 20, 2004, at Ahsahka, Idaho. ________________________ William P. Connor, Ph.D. U.S. Fish and Wildlife Service In season data (PITTAGIS and DART)

Post-season Analyses

Post-season evaluation on flow effects NAJFM 23: NAJFM 23:

Post-season evaluation temperature effects NAJFM 23: NAJFM 23:

Post-season evaluation of survival effects Estimated survival to the Estimated survival to the tailrace of Lower Granite tailrace of Lower Granite Dam for groups of fish Dam for groups of fish called cohorts called cohorts Four cohorts per year Four cohorts per year Years 1998 to 2003 Years 1998 to 2003 NAJFM 23:

Post-season evaluation of survival effects NAJFM 23:

Post-season evaluation of survival effects NAJFM 23:

Objectives: 1)Determine how fish respond to the cool water provided by summer flow augmentation from Dworshak reservoir 2) Determine the relationship between flow, water velocity, and juvenile fall Chinook salmon migration rates Behavioral Studies

Temperature effects of Flow Augmentation

Red Wolf Bridge Bridge Fish Temp (C) Depth (ft) Fish River Bottom Blue BlueBridge Example of Temperature Selection by a Radio-tagged Fall Chinook Salmon

Velocity effects of Flow Augmentation

Effects of flow on fish travel rates 30* 44** 44**46.4*** Flow (kcfs) Rate (km/d) Upper Reservoir Mid Reservoir Forebay Cross-sectional velocity profiles * Hypothetical base flow ** Base flow + 14 kcfs from Dworshak *** Base flow + 14 kcfs kcfs from Brownlee

Behavioral effects of Flow Augmentation

LGR Dam Example of an upstream excursion made by a radio-tagged juvenile fall Chinook salmon Forebay Granite Point Water Canyon Steptoe Canyon Redwolf Bridge Blue Bridge Couse Creek Note: Blue circles indicate locations of radio-telemetry detection sites

Upstream Excursions 25 fish (17%) wandered back and forth between Lower 25 fish (17%) wandered back and forth between Lower Granite Dam and our forebay detection sites (1.5 km Granite Dam and our forebay detection sites (1.5 km upstream) in 2003 upstream) in 2003 Median forebay residence time was 47 h Median forebay residence time was 47 h 9% of all fish tagged in 2002 and 2003 made excursions 9% of all fish tagged in 2002 and 2003 made excursions upstream of the forebay upstream of the forebay Most excursions were initiated from the forebay Most excursions were initiated from the forebay Excursion distances ranged from 5 to 33 km Excursion distances ranged from 5 to 33 km Excursion times ranged from 3 to 92 h Excursion times ranged from 3 to 92 h Some fish made multiple upstream excursions Some fish made multiple upstream excursions

Future Direction of Project Continue to provide managers with in season PIT-tag data Continue to provide managers with in season PIT-tag data and post season analyses. and post season analyses. Increase the number of fish PIT tagged to extend analyses Increase the number of fish PIT tagged to extend analyses further downstream to help understand issues such as further downstream to help understand issues such as summer spill. summer spill. Collect at least one additional year of data on radio-tagged Collect at least one additional year of data on radio-tagged fish to clarify the relationship between flow, velocity, and fish to clarify the relationship between flow, velocity, and fish migration rate fish migration rate Smaller tags, currently being developed, will allow us to Smaller tags, currently being developed, will allow us to better represent the juvenile fall Chinook population in better represent the juvenile fall Chinook population in future radio telemetry studies future radio telemetry studies Determine if the cool water provided by summer flow Determine if the cool water provided by summer flow augmentation enable some fish to delay their migration augmentation enable some fish to delay their migration until the following spring until the following spring