The Brown-headed Cowbird (Molothrus ateris) an 8-inch member of the Icteridae family. Centuries ago this bird followed bison herds on the Great Plains. It fed on insects flushed from the grasses by the grazing animals. Today it can be seen following cattle and is found over all of the United States.
The most well-known plumage of brown-headed cowbirds is that of the male. Their wings and body are black overall with a faint green sheen. As its name suggests, this cowbird has a brown head with a short conical bill. The female is mostly brown with hints of gray. It has a faint malar mark. Females can often be confused with a number of sparrows.
Brown-headed cowbirds live near farms, fields, prairies, wood edges, and river groves. They favor open or fairly semi-open habitats throughout the year.
This cowbird's diet includes seeds and insects. During the summer and winter various kinds of seeds make up most of what it eats. It also feeds on grasshoppers, beetles, caterpillars, spiders, and millipedes.
Being a brood parasite, its eggs and young are cared for by other species of birds. It is known to lay eggs in the nests of over 220 species. Out of those, 140 of them are known to raise the young cowbirds.
The female lays whitish eggs with brown and gray spots concentrated at the larger end. Usually, one eggs is laid per nest. More than 70 eggs can be laid in one breeding season.