The Alaska Department of Fish and Game (ADF&G) has forecast a total sockeye salmon run of 41.47 million in Bristol Bay, which would allow for a commercial harvest of 29.01 million fish next year. The run is almost identical to the most recent 10-year average of total runs (41.39 million) and 27 percent greater than the long-term mean of 32.76 million sockeye.
ADF&G’s Bristol Bay forecast is the sum of individual predictions of nine river systems – Kvichak, Alagnak, Naknek, Egegik, Ugashik, Wood, Igushik, Nushagak and Togiak rivers – and four age classes – ages 1.2, 1.3, 2.2, and 2.3, plus ages 0.3 and 1.4 for the Nushagak River. Adult escapement and return data from brood years 1972–2013 were also used in the analyses.
The run forecast to each district and river system is as follows: 16.07 million to Naknek-Kvichak District (7.76 million to the Kvichak River; 4.04 million to the Alagnak River and 4.27 million to the Naknek River); 10.65 million to the Egegik District; 5.46 million to the Ugashik District; 8.62 million to the Nushagak District (5.5 million to the Wood River; 1.87 million to the Nushagak River and 1.25 million to the Igushik River); and 660,000 to the Togiak District.
The department has forecast the 2017 run will consist of 12.05 million age-1.2 fish (29 percent of the total run), 9.35 million age-2.2 fish (23 percent of the total run), 16.5 million age-1.3 fish (40 percent of the total run) and 3.5 million age-2.3 fish (8 percent of the total run).
Historically, sockeye salmon runs to Bristol Bay have been highly variable – as such forecasting future salmon returns is “inherently difficult and uncertain,” said ADF&G. The Bristol Bay total run has averaged 32.76 million from 1963 through 2016 and has averaged 41.39 million fish during the most recent 10-year period.
Since 2001, ADF&G’s forecasts have on average under-forecast the run by 10 percent – ranging from 44 percent below actual run in 2014 to 19 percent above 2011’s actual run.
Forecasted harvests have had a mean absolute percent error of 15 percent since 2011.
