Trio of male brown-headed cowbirds
Three male brown-headed cowbirds perched in the treetops next to the Rideau River, June 30, 2013. The brown-headed cowbird is unusual in that it practices nest parasitism. Cowbirds do not rear their own young. The female lays an egg in another bird’s nest and the cowbird chick hatches and is reared by the other birds. It pushes the chicks of the host birds out of the nest so it does not compete for food. Some species of songbird have adapted to this threat in building dummy nests to lure the cowbird to leave its eggs, leaving them free to rear their own broods.
Photographed and posted by Geoffrey
