Yukon River Chinook Salmon: Stock Status, Harvest, and Management
Danielle F. Evenson, Steve J. Hayes, Gene Sandone, and Daniel J. Bergstrom
Abstract.—This paper reviews and describes the status of stocks, fisheries, and management of Chinook salmon Oncorhynchus tshawytscha in the Yukon River. The Alaska Department of Fish and Game (ADF&G) manages the Yukon commercial and subsistence fisheries in the Alaskan portion of the drainage and by the Canadian Department of Fisheries and Oceans in the portion in Yukon Territory. The salmon are managed to achieve escapement goals for spawning, to maintain sustained production based upon perceived run strength, and to accomplish approved fishery management plans. The Chinook salmon stocks of the Yukon River have experienced considerable variation in abundance and harvest over the past 50 years. After experiencing poor runs from 1998–2000, Chinook salmon escapement goals have been generally met throughout the Alaska portion of the Yukon River drainage during the past five years, 2004–2008. Typically, about 50% of the Chinook salmon reproduction occurs in Canada. The escapement goal into Canada was not met in 2007 and 2008. The average escapement to the Canadian portion of the Yukon River drainage from 2004 to 2008 was 49,500 Chinook salmon (range 32,500 to 68,500 fish), which was similar to the historical baseline ten-year average (1989–1998) of 50,800 fish. The age-class composition of the Canadian-origin Chinook salmon return from brood-years 1979–1998 indicated a decrease in age-7 salmon from an average of 22% from brood years 1979–1982 to an average of only 8% from brood years 1983–2000. In Alaska, the five-year (2004–2008) average commercial and subsistence combined harvest of 86,573 Chinook salmon was a 55% decrease from 1989 to 1998 average of 156,092 fish. In Canada, total harvest from all sources (domestic, aboriginal, sport, and commercial) from 1980 to 1997 ranged between 10,729 and 22,896 fish. The ten year (1999–2008) average total harvest of 8,739 Chinook salmon was 81% below the lower end of this range. While certainly challenges exist, careful management through the regulation of the fisheries to permit adequate escapements for spawning should ensure the sustainability of the resource for future generations.