Pollutants cause birds to sing tainted love songs
Traces of a chemical once used by power plants leave birds looking fit, but singing another tune altogether.
Wild chickadees exposed to permitted levels of polychlorinated biphenyls (PCBs) can't keep a tune as well as other birds.
Because females go for males with the best songs, PCB-exposed birds might lose out on mates, says Sara DeLeon, an ecologist at Cornell University in Ithaca, New York, who presented her research at a recent conference at the university.
"The birds are living, not dying, but [PCBs] are affecting some part of their life cycle," she says.
Researchers have long known that some chemicals, such DDT, can throw off a bird's song, but none have determined whether exposure to trace amounts in the wild can influence songs and mating.