Brown-Headed Cowbird – Molothrus ater – also known as Le vacher à tête brune (French), Tordo negro (Spanish), Braunkopf-Kuhstärling (German), bruinkop-koevogel (Dutch), Rudagalvis karviaganis (Latvian?), Brunhodetrupial (Norwegian).
Still cleaning out the digital closet of old photos.
The Brown-Headed Cowbird is fascinating for the following reason:
“The Brown-headed Cowbird is the only brood parasite common across North America. A female cowbird makes no nest of her own, but instead lays her eggs in the nests of other bird species, who then raise the young cowbirds.”
Called the “cowbird” because:
“Originally a bison-following bird of the Great Plains, the Brown-headed Cowbird spread eastward in the 1800s as forests were cleared. It is a common bird across most of North America, but numbers are declining in most areas. Its habit of nest parasitism can cause the decline of species with small populations, such as Kirtland’s Warbler and Black-capped Vireo.”
When I first became interested in birding, Brown-Headed Cowbirds were so common that, ironically, I never bothered taking their picture. Then I moved and realized they really aren’t “everywhere,” for they prefer the open areas to the more urban spots. As fall came, however, they moved into mixed flocks with Red-Winged Blackbirds and others, or into giant flocks of just Brown-Headed Cowbirds (see the first photo). They then became quite common, again.
The male is easily identified by the black body and brown head. The female, however, looks like your typical “little brown bird.” Larger than a finch, but with a finch-ish beak (see second photo), the easiest way to identify it is by looking to see if male Brown-Headed Cowbirds are around. Compare the female Brown-Headed Cowbird to the female Red-Winged Blackbird, female House Sparrow, and the female House Finch.
During the summer, the Brown-Headed Cowbird lives throughout the contiguous United States. In the winter, the bird moves its range south and occupies most of the Eastern and Southeastern United States and Mexico.
Both photos taken with the Canon Digital Rebel XT / 350D and a Sigma 70-300mm Lens. The top photo was taken on October 24, 2007 in rural Mercer County, Illinois. The bottom photo of the female taken on April 29, 2007 in Davenport, Iowa.
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I really enjoy all the information you provide on your birds. I have to start saving money for a better camera like yours!
December 25th, 2007 at 11:23 amWishing you and yours the best this Christmas Day!
Best wishes for the new year as well!
December 25th, 2007 at 5:26 pmMerry Christmas! Great information on the Cowbird. I’ve only seen one of the males in my backyard early on this past summer. I managed to snap a pic of him while he was there under my feeder. My yard is wooded and with them prefering more open areas, I probably don’t get them alot. Thanks for your informational posts!
December 25th, 2007 at 5:32 pmThanks for the comments!
Chicago Nature Lady – the camera and lens are more affordable than you think! Drop me line sometime if you are interested and I can point you to the places I bought my stuff!
January 7th, 2008 at 11:10 pm