Biological process underlying coho salmon die-offs unlocked

Chemical linked to death of coho salmon in Puget Sound

Coho salmon continue to die in Puget Sound creeks after rainstorms. The deaths were linked to bits of car tires shed from road friction into stormwater runoff in 2018. Washington State University’s (WSU) Puyallup Research and Extension Center identified a tire preservative, known as 6PPD, as the main culprit in 2020. Now, after years of digging, WSU Ph.D. student Stephanie Blair figured out how that chemical kills fish. 6PPD becomes a toxic chem…

Biological process underlying coho salmon die-offs unlocked

For years, scientists at Washington State University's Puyallup Research & Extension Center have been working to untangle a mystery: Why do coho salmon in Puget Sound creeks seem to suffocate after rainstorms—rising to the surface, gaping, and swimming in circles before dying?

WSU Researchers Uncover Biological Mechanism Behind Coho Salmon Die-Offs

For years, the mysterious and alarming deaths of coho salmon in Puget Sound creeks after rainstorms have perplexed scientists and conservationists alike. These iconic silver salmon, native to the Pacific Northwest, exhibited troubling behaviors as they suffocated, gaping and swimming erratically at the water’s surface before dying. The phenomenon, often referred to as “coho urban runoff mortality syndrome,” had long resisted clear scientific exp…

WSU team unlocks biological process behind coho die-offs

PUYALLUP, WA – For years, scientists at Washington State University’s Puyallup Research & Extension Center have been working to untangle a mystery: Why do coho salmon in Puget Sound creeks seem to suffocate after rainstorms — rising to the surface, gaping, and swimming in circles before dying? In 2018, the die-offs were linked to bits of car tires shed by friction and washed into the stormwater runoff. In 2020, researchers zeroed in on one parti…