In hot water, sockeye salmon will be trapped, trucked
LEWISTON, Idaho — Sockeye salmon at risk from high water temperatures will be captured at an eastern Washington dam to save as many of the endangered fish headed for Idaho as possible, wildlife managers said.
The Idaho Department of Fish and Game told The Lewiston Tribune in a story published Friday that workers will start trapping the salmon this week at Lower Granite Dam on the Snake River and truck them to hatcheries to be artificially spawned or to Redfish Lake in central Idaho for release.
Lance Hebdon of Fish and Game said water temperatures in the Snake and Salmon rivers have been as high as 76 degrees, which can be lethal for salmon.
Fish and Game fisheries biologist Jonathan Ebel said Salmon River flows in one area are about 25% of average, and water temperatures are as high as 76 degrees.
Much of the Northwest has been in a drought and in the last week has experienced record heat.
“When flows are low and temperatures are high, it warms up no matter where you are,” Ebel said.
Adult sockeye salmon returning from the ocean travel 900 miles up the Columbia, Snake and Salmon rivers to high-elevation Sawtooth basin lakes in central Idaho. There are eight dams total that the fish have to surmount – four on the Columbia and four on the Snake River.
Snake River sockeye teetered on the brink of extinction in the early 1990s. They have been the focus of an intense recovery program after being listed for federal protection in 1991.
The goal of a self-sustaining wild population took a hit in 2015 when warm water in the Columbia River Basin killed nearly all the returning adult fish, with only 55 completing the journey to central Idaho.
That was the last year wildlife managers trapped sockeye salmon at Lower Granite Dam, capturing 35 fish. Of the 90 total fish that year, five were released to spawn naturally and 85 went to the Eagle Fish Hatchery in southwestern Idaho for artificial spawning.
Fisheries managers said that through Tuesday, nine sockeye salmon had made it to Lower Granite Dam.
Early indications are that as many as 1,300 Snake River sockeye could pass Bonneville Dam and, based on an average survival rate, 800 could make it to Lower Granite Dam.
So far, water temperatures in the Columbia and Snake rivers below the dams are cooler than those recorded at the same time in 2015, fisheries managers said.