Project title: Juvenile Chinook Salmon Movement, Overwinter Survival, and Outmigration Timing in the Chena River, Alaska
Personnel Olivia Edwards (MS Student) Funding source(s): Alaska Department of Fish and Game Project description: Since 2001, Chinook Salmon returning to the Yukon River drainage have been designated as a stock of concern by the Alaska Board of Fisheries, and the Chena River supports one of the largest spawning stocks in the Alaskan portion of the Yukon River drainage. The Chena River juvenile Chinook Salmon study will provide a method to estimate the outmigration timing and magnitude of smolt production from several rearing areas on a highly utilized stock. These estimates will lead to a mark-recapture study design that generates accurate and precise estimates of smolt abundance and marine survival that can improve the stock assessment models that are used to establish sustainable escapement goals. These improved models will aid managers when making decisions about the Yukon River’s important subsistence, commercial, and sport fisheries. Objectives are to, 1) describe immigration and/or emigration from designated fall rearing areas by Chinook Salmon parr, 2) quantify outmigration timing for Chinook salmon smolts originating from different rearing areas across the Chena River basin, 3) estimate relative overwinter survival of Chinook Salmon parr to smolt among rearing areas located throughout the Chena River basin. We will capture and PIT tag Chinook Salmon parr during the fall of 2018 at sites located in the designated rearing areas (North, Middle, and South Forks, upper mainstem, and the Little Chena River). Within each area, one or more streams and/or reaches will be selected to represent the rearing area. Movements of PIT tagged fish throughout the winter and during outmigration will be monitored using PIT tag antenna arrays that are placed on the river bottom at the mouth of the designated rearing area or the stream(s) that represent the area and the Moose Creek Dam. Fish passing over the array will activate their PIT tag and individual tag number, timing, and swimming direction (upstream or downstream) will be recorded. PIT arrays will be installed and tested during late-July and early August prior to juvenile fish collection and tagging. Travel times from each rearing area above the dam will be calculated from the PIT tag arrays at each area and the Moose Creek Dam. In addition, detection and survival probabilities will be calculated for all rearing areas above the dam using a single release-recapture model that has been successfully implemented on the Snake and Columbia rivers. This sampling design will generate accurate and precise estimates of timing into and out of the rearing areas as well as relative overwinter survival. These improved models will aid managers when making decisions about the Yukon River’s important subsistence, commercial, and sport fisheries. The project will also identify and characterize important fall rearing areas for juvenile Chinook Salmon. All components of this study are identified by the Yukon River Panel as information needs/actions. In addition, the ADF&G Chinook Salmon Initiative has identified juvenile Chinook Salmon information as an information gap for the Yukon River and the Chena River is one of the largest contributors to this stock. Co-Investigators: James Savereide (ADFG) Andy Seitz (UAF) Collaborators: University of Alaska Fairbanks, USGS, Alaska Department of Fish and Game |
Outreach:
Presentations: Edwards, O.N., J.A. Falke, J.W. Savereide, and A.C. Seitz. 2020. Summer growth and movement behavior of juvenile Chinook Salmon in the Chena River, Alaska. Alaska Chapter of the American Fisheries Society Annual Meeting, Fairbanks, Alaska, 23 March to 26 March, 2020. Edwards, O.N., J.A. Falke, J.W. Savereide, and A.C. Seitz. 2019. Juvenile Chinook Salmon (Oncorhynchus tshawytscha) movement, overwinter survival, and outmigration timing in the Chena River, Alaska. American Fisheries Society and The Wildlife Society Joint Annual Conference, Reno, Nevada, 29 September to 3 October, 2019. Edwards, O., Falke, J., Savereide, J., and A. Seitz. 2019. Juvenile Chinook Salmon (Oncorhynchus tshawytscha) movement, overwinter survival, and outmigration timing in the Chena River, Alaska. Alaska Chapter American Fisheries Society Annual Meeting, Sitka, Alaska, 19-22 March, 2019. |