The annual pre-spawning salmon mortality study at the Suquamish Tribe’s Grovers Creek Hatchery takes a different twist each year.
After six years of learning how coho and chum salmon are affected by runoff from urban streets, scientists are narrowing down which pollutant is killing fish. This year, they focused on how tire residue in water affects juvenile and adult coho and chum salmon.
“We want to figure out which concentration of the tire residue in the water will kill fish and how long after exposure do the fish become sick and die,” said Jen McIntyre, aquatic ecotoxicologist for Washington State University, who has overseen the last few years of the project.