Brown-headed Cowbird, Molothrus ater, male
Bombay Hook National Wildlife Refuge, DE
Cowbirds get their name from their habit of following large grazing animals (such as bison or cattle) in search of the insects that they stir up. Cowbirds are brood parasites: the females lay their eggs in the nests of other bird species for them to rear and provide no parental care of their own.
(Order Passeriformes, Family Icteridae)