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Summer Chum Salmon Radio Telemetry Study. Sean Larson Alaska Department of Fish and Game Division of Commercial Fisheries. Summary. ADF&G is implementing a radio telemetry study on Yukon summer chum salmon.
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Summer Chum Salmon Radio Telemetry Study Sean Larson Alaska Department of Fish and Game Division of Commercial Fisheries
Summary ADF&G is implementing a radio telemetry study on Yukon summer chum salmon • Use drift gillnets to catch and tag 1200 chum salmon near Russian Mission with spaghetti and radio tags • Track tagged salmon upriver with remote tracking stations and aerial surveys • First major effort to estimate summer chum run timing, distribution, and abundance, with consideration for specific stocks
Importance • Fishing pressure is increasing • Need this study to manage specific stock groups • Need more information • Escapement estimates for spawning tributaries • Distribution among spawning areas • Stock specific run characteristics • AnvikRiver
Anvik River • Before 2003: Summer chum salmon escapement represented 46% of fish passage estimated at the sonar near Pilot Station • After 2003:Average proportion has dropped to 23% • Where are they going?
Primary Objectives • Estimate stock specific: • Run timing • Migration rates • Movement patterns • Distribution • Identify important spawning tributaries • Stock contribution to the overall run • Estimate drainagewide escapement • Identify the relationship between the Anvik River sonar and the sonar near Pilot Station
Previous RT Studies • Chinook (2002-2004) • Fall Chum (1996-2001) • Summer Chum (2004) • Small feasibility study • 200 tagged • Relatively successful
Russian Mission Russian Mission has several important geographic and fishery features that make it ideal for tagging • Beyond most harvests (minimal tag loss) • Narrow channel (easy capture) • EF Andreafsky River has a weir • Previous tagging efforts
Tagging • Two crews • Up to 7.5 h/d • 7 d/w • 5 weeks • Max of 3 fish per drift • Gillnet configurations • 4.5” and 4.25” mesh size • 10 f long shackled together as needed • 7.6 m deep • Thicker and softer #21 seine twine to minimize injuries
All fish will be handled as gently as possible to minimize stress (and placed in flow through water tank)
Spaghetti tags will be white and located against the dorsal fin
Radio tags will have an antennae protruding out of the mouth Should examine for both tags
Tracking Upriver
How Many Are There? • Monitoring/Assessment Projects Anvik Sonar - Gisasa River Weir - Henshaw Creek Weir - Chena River Tower - Salcha River Tower • Mark-recapture abundance estimate
Where do they go? • Towers & Aerial Surveys • Monitoring/Assessment Projects Anvik Sonar - Gisasa River Weir - Henshaw Creek Weir - Chena River Tower - Salcha River Tower • Fishermen
Summary • Tag 1200 summer chums near RM • Track salmon via towers and aircraft • Stock specific: • Distribution • Abundance • Run timing • Drainage wide abundance • Evaluate existing monitoring projects • Please keep an eye out for tagged fish
Alaska Sustainable Salmon Fund Alaska's allocation of funds from the federal Pacific Coastal Salmon Recovery Fund
Questions? Photo Credit: Peter Mather