Taku River Sockeye Salmon Stock Assessment Review and Escapement Goal Revision

The primary goals of this project are to bilaterally review stock assessment work on the Taku River and make recommendations for improving the program, and to reevaluate the escapement goal for Taku River sockeye salmon. The Taku River is a transboundary river system that originates in the Stikine plateau of northwestern British Columbia and terminates in Taku Inlet in Southeast Alaska. The river produces one of the largest runs of sockeye salmon in Southeast Alaska, and is jointly managed by the Alaska Department of Fish and Game (ADF&G) and the Department of Fisheries and Oceans Canada (DFO). The U.S./Canada Pacific Salmon Treaty of 1985, and subsequent additions to the original treaty, established conservation (71,000 to 80,000 escapement goal) and harvest sharing (percentage sharing of the allowable catch) objectives for the Taku River sockeye salmon run. Inseason estimates of the spawning escapement of Taku River sockeye salmon, obtained through a mark-recapture program, are needed to fulfill the escapement goal and international harvest sharing requirements for stocks specified by the Pacific Salmon Treaty.

The Taku River is a large and complex system, with multiple tributaries and lake systems, as well as inriver indigenous, personal use, subsistence, and commercial sockeye salmon fisheries, which create special challenges for mark-recapture work in the drainage and for escapement goal analysis. Improvements to inseason and total escapement estimates of sockeye salmon on the Taku River will affect all aspects of fisheries management and lead to more efficient and sustainable utilization of the resource by the U.S. and Canada. Among the stock assessment challenges that will be examined by the review team includes issues with tag loss, tag-induced mortality, and tag mis-identification or non-reporting in the mark-recapture project, fish sampling protocols at the Canyon Island fish wheels, improving estimates of the distribution of mainstem and tributary spawners in the drainage, and assessing weir projects on Canadian tributaries. Additionally, methodologies to compliment the current program will be explored with the intention of strengthening both inseason and post season estimates of Taku River sockeye salmon.

This project will also allow for a detailed compilation and synthesis of all relevant data and science gathered since the last revision of the Taku River sockeye escapement goal, and allow application of current knowledge to the refinement of the escapement goal. Improvements to the escapement goal will ensure that management is focused on providing escapements that will ultimately lead to sustained yields and stable fisheries well into the future.