This paper establishes a biological frame of reference for spawner abundances of the Coho Salmon (Oncorhynchus kisutch) stock aggregate originating in the Taku River in northwestern British Columbia. This transboundary stock aggregate is managed cooperatively by Canada and the US under the Pacific Salmon Treaty. The project focused on fitting alternative Spawner-Recruit (SR) models and estimating biological benchmarks for each model.

A long time series of good-quality data are available for Taku River Coho Salmon at the aggregate level including: spawner estimates based on a consistent mark-recapture survey covering the period 1987-2013; recruitment estimates for the 1987 to 2009 brood years based on catch and escapement data and coded-wire tag recoveries in Alaskan and Canadian fisheries and surveys; and annual age and sex composition estimates. Estimates of biological benchmarks for the Taku River Coho Salmon aggregate were robust to alternative assumptions.