Common pesticide makes migrating birds anorexic

When birds migrate, timing is everything. Fly too late, and they miss the peak season for finding good food, a good mate, or a good nest site. But that’s just what may happen to migrants unlucky enough to eat pesticide-laced seeds, new research shows. Toxicologists studying white-crowned sparrows have shown that these large, grayish birds become anorexic after eating neonicotinoid pesticides, causing them to lose weight and delay their southward journeys. The study might apply to other birds as well—and help explain the dramatic songbird decline of recent decades, researchers say.

Neonicotinoids are the world’s most widely used class of pesticide. They protect seeds—and the plants that grow from them—from insects resistant to other pesticides. But scientists have recently found that they can decimate pollinators like honey bees and bumble bees. Such concerns led the European Union to ban three of these compounds in 2018.

www.sciencemag.org/common-pesticide-makes-migrating-birds-anorexic