Brown-headed Cowbird - Molothrus ater - Vacher à tête brune
A male Brown-headed Cowbird displaying near Wild Horse in southeastern Alberta, Canada.
Similar to the European Cuckoo, the Cowbird is a brood parasite. Male and females form pairs but then the female wanders off to locate and lay eggs in the nests of other small birds. The unwitting hosts then raise the baby Cowbird as their own after the young interloper ejects the real eggs or babies from the nest.
The name Cowbird comes from the species' habit of flocking around the feet of cattle, feeding on the insects disturbed by their hooves. Bisonbird might have been the name had the history of North America unfolded on a different path.