Alaska Fisheries Sonar

Yukon (Eagle) River

King Salmon

Yukon king salmon may spend up to two years in freshwater as juveniles and one to six years in the ocean.


Yukon chum salmon migrate to the ocean shortly after emerging from the gravel and spend two to six years in the ocean.

The Fish

The Yukon River Eagle sonar site monitors king and fall chum salmon destined for river waters in Canada. About 50 percent of Yukon king salmon and 25 percent of fall chum salmon come from Canadian-origin stocks. Canadian-origin king salmon arrive early in the season, whereas Canadian-origin chum salmon arrive late in the season. King salmon migrate past the Eagle sonar site from about July 1 to mid-August. Fall chum salmon, on the other hand, migrate past the Eagle sonar site from about mid-August through the first week of September.

Yukon king salmon can weigh as much as 90 pounds and spawn as far as 2,000 miles upstream. Two genetically distinct stocks of chum return to the Yukon River - summer and fall chum. Summer chum salmon spawn mostly in the lower 500 miles of the Yukon and weigh an average of seven pounds. The fall chum salmon monitored at the Eagle sonar site spawn in Canada and weigh an average of seven to eight pounds.

Because Yukon king and fall chum salmon support the livelihoods of Alaskans and Canadians, they are jointly managed under an international agreement. Under the Yukon River Salmon Agreement, the US and Canada manage their fisheries to ensure enough salmon are available to meet escapement requirements and to share the fish available for harvest.

Under the agreement, the upper Yukon River escapement goals were 33,000 to 43,000 king salmon and more than 80,000 chum salmon. However, these goals were developed from and subsequently monitored by the Canadian mark-recapture program located just upstream of the Alaska/Yukon border. Since 2008, the Yukon River Panel has adopted Interim Management Escapement Goals (IMEG) based on information from the Eagle sonar program. In 2011 the goal was 42,500 to 55,000 king salmon and 70,000 to 104,000 chum salmon. These new goals are temporary until additional years of data from the Eagle sonar program become available. For more details see pages 67 - 68 of the Yukon River 2010 Season Summary and 2011 Season Outlook (PDF 9,025 kB).