Three Common Pesticides Threaten Endangered Salmon in U.S.

U.S. government fisheries biologists say there is “overwhelming evidence” that three pesticides long used on crops, lawns, and in mosquito control are damaging the ability of endangered salmon in the Pacific Northwest to smell, forage, reproduce, and even swim. In a 377-page study, biologists from the U.S. National Marine Fisheries Service said that ongoing use of the three pesticides — Chloripyrifos, Diazinon, and Malathion — will continue to harm the “viability” of more than two dozen stocks of endangered salmon. The scientific opinion was issued in connection with a federal lawsuit seeking to halt use of the pesticides because they threaten the fish under the Endangered Species Act. The pesticides — used on more than 100 crops and, in Malathion’s case, on lawns and shrubs — are washed into streams. There, they impair the salmon’s ability to swim, blunt the sense of smell in young salmon that teaches them to avoid predators, and inhibit adult male salmon from smelling female salmon at spawning time, the scientists said.