MINNEAPOLIS — Pesticides that kill insects can also have short-term effects on seed-eating birds. Ingesting even small amounts of imidacloprid, a common neonicotinoid pesticide, can disorient migratory white-crowned sparrows, researchers report.
Neonicotinoid pesticides were designed to be safer than traditional pesticides: toxic to insects, but comparatively harmless to other animals. But the new findings add to evidence suggesting that the widely used pesticides, which are chemically similar to nicotine, might be sending ecological ripples beyond the intended targets.
In lab studies, researchers captured wild white-crowned sparrows, Zonotrichia leucophrys, that were migrating north and fed them small doses of imidacloprid for three days — the amount that birds would get from eating a few pesticide-coated wheat seeds. The birds that ate the pesticides lost weight, study coauthor Margaret Eng reported November 15 at the annual