photo © Judy Howle

Cool facts

  • Cowbirds are incapable of nesting, incubating or raising their own chicks. Instead, they lay their eggs in the nests of other bird species, which then raise the young cowbirds.
  • When a cowbird lays an egg in another bird’s nest (called the “host” bird), it usually tosses out one of the host’s eggs. If a host bird removes a cowbird egg, the cowbird may retaliate by returning and destroying all of the host’s remaining eggs.


Song is a low “glug, glug” followed by slurred whistles that end on a very high pitch.
To listen to the songs of this species check out the ‘How to Identify’ section of its Focal Species page.


Grassy areas, yards, brushy areas.


Primarily insects and other invertebrates, seeds, and fruit.

Did you know?

Brown-headed Cowbird female
photo © Judy Howle
  • The Brown-headed Cowbird lays eggs in the nests of many different species of birds, but most females specialize on one particular host species.
  • In one case, a cowbird laid her egg in the nest of a Ruby-throated Hummingbird. The egg completely filled the nest and never hatched.
  • Many birds have evolved ways of rejecting cowbird eggs. The Yellow Warbler, for example, will build a new nest lining over the cowbird’s eggs if she finds them in her nest.