Every fall, more than half of the coho salmon that return to Puget Sound’s urban streams die before they can spawn. In some streams, all of them die. But scientists didn’t know why.
Now, a team led by researchers at Washington State University and the University of Washington has discovered the answer. When it rains, stormwater flushes bits of aging vehicle tires on roads into neighboring streams. The killer is in the mix of chemicals that leach from tire wear particles: a molecule related to a preservative that keeps tires from breaking down too quickly. » More …
A report by scientists with WSU’s State of Washington Water Research Center could help inform decision makers and planners in watersheds across the state, as they develop projects that balance growth with the needs of threatened salmon and steelhead.
“Our guidance highlights available approaches that can benefit endangered species and their habitat, as well as Washingtonians’ increasing need for high-quality water,” said Stephen Katz, project lead and » More …
WSU scientists have discovered that different species of salmon have varying reactions to polluted stormwater runoff.
In a recent paper published in the journal Environmental Pollution, scientists found that coho salmon became sick and nearly died, within just a few hours of exposure to polluted stormwater. But chum salmon showed no signs of ill-effects after prolonged exposure to the same water.
Columbia River Chinook salmon have lost as much as two-thirds of their genetic diversity, Washington State University researchers have found.
The researchers reached this conclusion after extracting DNA from scores of bone samples — some harvested as many as 7,000 years ago — and comparing them to the DNA of Chinook currently swimming in the Snake and Columbia rivers.
Preserving genetic diversity is a central goal of the Endangered Species Act, in part because it helps a species adapt to changing environments. Yet it is rarely measured to this degree. » More …
It turns out that sex can move mountains. A Washington State University researcher has found that the mating habits of salmon can alter the profile of stream beds, affecting the evolution of an entire watershed. His study is one of the first to quantitatively show that salmon can influence the shape of the land.