Provisional Estimates of Numbers and Biomass for Natural-Origin and Hatchery-Origin Pink, Chum, and Sockeye Salmon in the North Pacific, 1952-2015

This report provides provisional abundance estimates for pink, chum, and sockeye salmon in major regions of the North Pacific from 1952 through 2015 in terms of: numbers of natural- origin and hatchery-origin salmon returns (i.e., catch plus escapement), numbers and biomass (metric tonnes) of total returns (natural-origin and hatchery-origin), as well as biomass expanded to include immature salmon remaining at sea. Estimates in this report update and replace those published previously. Data quality and methodology, which vary among regions and years, are briefly discussed. Temporal abundance patterns generally follow commercial catch patterns documented elsewhere. Results suggest that the proportion of hatchery-origin chum salmon abundance peaked in the late 1990’s at ~70%, and is currently ~45%. Hatchery-origin pink and sockeye salmon currently constitute ~19% and ~4% of the total returns for these species, respectively. Total adult abundance and biomass peaked in 2009 (910 million pink, chum, and sockeye salmon; 1.7 million metric tonnes); when immature salmon were included, total biomass exceeded 5 million metric tonnes in 2009 and again in 2013.