Dead Columbia River sockeye found in lower Deschutes

THE DALLES, Ore. — Oregon biologists have found about 50 dead or distressed sockeye salmon in the lower Deschutes River plus collected several dead sockeye along the banks of the Columbia River just upstream of the Deschutes.

Early pathology results suggest the fish died from columnaris, a bacterial infection typically associated with high water temperature and low levels of dissolved oxygen.

Rod French, an Oregon Department of Fish and Wildlife biologist, said the dead sockeye appear to be fish bound for the upper Columbia that entered the Deschutes for its colder water.

Sockeye are being reintroduced into the upper Deschutes upstream of the Pelton-Round Butte Dam complex. However those sockeye are fin-clipped, while the upper Columbia sockeye are not.

French said there could be additional fish die-offs if this year’s drought conditions continue.

“These low water levels and high temperatures can be lethal to some fish,” he said. “If there is any good news, it’s that the native Deschutes redband trout and steelhead are genetically adapted to withstand periods of warmer water.”

In recent days, water temperatures Columbia River has been hovering around 73 degrees F. Unlike the Columbia, Deschutes temperatures fluctuate on a daily basis, where they have been ranging from 68 to 74 degrees. Sockeye can be more affected by warm water than other cold water fish like trout, steelhead, and even chinook salmon.