Blue Lake fish dead on purpose
Courtesy photo Above: A Washington Department of Fish and Wildlife crew laces Blue Lake with rotenone, a natural pesticide that prevents undesirable species from obtaining oxygen. Below: Perch and other species wash up on the lakeshore at Blue Lake. The fish are being eliminated to make the lake safe for trout.
Courtesy photo Perch and other species wash up on the lakeshore at Blue Lake. The fish are being eliminated to make the lake safe for trout.
MOSES LAKE — The fish carcasses rotting along the rocky shoreline of Blue Lake are the result of the Washington Department of Fish and Wildlife’s deliberate efforts to poison the lake and kill everything in it.
“Absolutely, that was the purpose of the project,” said Jeff Korth, the Region 2 project manager for Fish and Wildlife. “We rid the lake of undesirable species and manage it for trout.”
Those undesirable species like perch were all killed with rotenone, a pesticide that prevents the fish from obtaining oxygen from the water, essentially suffocating them.
Korth said that trout are “not very good competitors” and their slow-growing fry don’t get enough to eat if they have to compete with other, faster-maturing species.
While dead fish litter the shoreline, Korth said most of the dead fish will sink to the bottom of the lake, where they will be quickly eaten by bacteria and provide a solid basis for the lake’s ecosystem when it is restocked in the spring.
Korth also said the dead fish that washed ashore will also decay and rot on their own fairly quickly, so the state has no need to clean them up.
“They won’t be there for much longer,” he said.
Rotenone is an insecticide derived from the seeds and stems of jicama vine, a bean plant indigenous to Mexico, and it prevents fish from taking oxygen through their gills. It has no effect on birds or mammals — including any scavengers that will eat the fish — and should dissipate from the lake water in about a month.
Korth said the lake will be restocked 12-inch trout and 3-inch “fingerlings” next spring.
Charles H. Featherstone can be reached via email at countygvt@columbiabasinherald.com.