When Nothing Smaller Will Do: Investigating Western Alaska Highly Mixed Chum Salmon Fisheries

For anadromous fish, freshwater life history and ecology is more visible and well-known in contrast with marine life history.  Marine migration can lead to interception in fisheries distant from natal streams and fishery composition studies often are limited to smaller areas local to a stock.  For Pacific salmon, harvest assessment along an entire coast provides a better picture of interactions between broad-scale distribution and local-scale human activities like fishing.  Western Alaska chum salmon fisheries occur at the edge of the Bering Sea and North Pacific Ocean, a region where salmon from throughout the species range feed and grow to maturity.  We conducted large-scale analysis of 3 years of salmon harvests beginning in 2009, the largest of its kind ever attempted.  This required new and developing technologies, innovative statistical analysis, and interaction with a diverse set of stakeholders.  This project involved 1) discovering and selecting novel SNPs; 2) assembling a rangewide genetic baseline; 3) collaboration with multiple laboratories; 4) genotyping 35,921 individuals for 96 SNPs for the baseline; and 5) genotyping 71,656 individuals harvested in 191 fishery strata along 3,300 km of coastline.  This entire project was accomplished in 4 years and completed concurrent with a similar-sized project on sockeye salmon.