Brown-headed Cowbird

They resemble New World orioles in general shape but have a finch-like head and beak. Adults have a short finch-like bill and dark eyes. The adult male is mainly iridescent black with a brown head. The adult female is grey with a pale throat and fine streaking on the underparts.

The Brown-headed Cowbird is classified as Least Concern. Does not qualify for a more at risk category. Widespread and abundant taxa are included in this category.

The Brown-headed Cowbird (Molothrus ater) is a small brood parasitic icterid of temperate to subtropical North America. They are permanent residents in the southern parts of their range; northern birds migrate to the southern United States and Mexico in winter, returning to their summer habitat about March/April. They resemble New World orioles in general shape but have a finch-like head and beak. Adults have a short finch-like bill and dark eyes. The adult male is mainly iridescent black with a brown head. More

The Brown-headed Cowbird is a stocky blackbird with a fascinating approach to raising its young. Females forgo building nests and instead put all their energy into producing eggs, sometimes more than three dozen a summer. These they lay in the nests of other birds, abandoning their young to foster parents, usually at the expense of at least some of the host’s own chicks. More

Brown-headed Cowbird range mapBreeding habitat Woodland, forest (especially deciduous), forest edge, grassland, farmlands, suburban gardens, shade trees. Description The smallest of our blackbirds (6 More

Brown-headed Cowbird - General Information The Brown-headed Cowbird (Molothrus ater) is North America's most notorious brood parasite. Instead of building their own nests, incubating their own eggs and raising their own nestlings, Brown-headed Cowbirds have a different breeding strategy. Cowbird females use other bird species as hosts - laying their eggs in the nests of other bird species and relying on these hosts to incubate and raise their chicks. More

The Brown-headed Cowbird is one of two species of cowbirds found in North America. Both species are brood parasites that lay their eggs in the nests other birds. Formerly occurring in the central grasslands of North America, wholesale clearing of forested land has allowed the Brown-headed Cowbird to extend its range across most of North America, and to increase its population dramatically. The male has an iridescent black body and a brown head. More

Before European settlement, the Brown-headed Cowbird followed bison herds across the prairies. Their parasitic nesting behaviour complemented this nomadic lifestyle. Their numbers expanded with the clearing of forested areas and the introduction of new grazing animals by settlers across North America. Brown-headed Cowbirds are now commonly seen at suburban birdfeeders. More

Brown-headed Cowbird has now greatly expanded its range throughout the modern landscape from coast to coast. Brown-headed Cowbirds are brood parasites, that is, they have completely abandoned the tasks of building nests, incubating eggs, and caring for hatchlings. Instead, each female deposits as many as 40 eggs per year in nests that belong to other bird species. More than 100 other species have provided host nests for cowbird eggs. More

Brown-headed Cowbirds emit a variety of easily-recognized calls, from liquid "glugs" to squeaks and whistles. Code Frequency Due to their conspicuous habits, Brown-headed Cowbirds were easy to detect wherever they occurred. Certain codes such as nest building and food for young are inappropriate for obligate brood parasites. More

The Brown-headed Cowbird has over 220 hosts. The other cowbird species have fewer known hosts, but all the species are generalists when it comes to choosing a host. This means that the eggs may look different from the hosts' eggs. The cowbird chicks grow quickly, and may consume most of the food the host brings. Starvation will often kill the host's chicks. In some species the cowbird chick will use its large size to push the other chicks out of the nest. More

The brown-headed cowbird, Molothrus ater, is a member of the blackbird family. The adult male is easily identified by his brown head and metallic green-black body. Female cowbirds are a pale brown with a gray-brown head. Both males and females have a length of about 7 More

Identification: The brown-headed cowbird is a member of the diverse blackbird family. Males are glossy black but have a brown head. Females are brownish gray. Juveniles are also gray but their breasts are streaked and lighter in appearance. All have a stout finch-like beak. Range: Brown-headed cowbirds are found from Saskatchewan and southern Canada, through the lower 48 states and into northern Mexico. They are migratory and arrive in Connecticut in March, remain through the summer and leave in late-September. More

The Brown-headed Cowbird (Molothrus ater) is a small icterid. Adults have a short finch-like bill and dark eyes. The adult male is mainly iridescent black with a brown head. The adult female is grey with a pale throat and fine streaking on the underparts. More

North American RangeThe Brown-headed Cowbird is well known-and widely disliked-for its practice of laying eggs in the nests of other species. Males are black birds with dull brown heads. Adult males are shiny black, while first-year males are duller black. Females are much smaller and solid brown with a whitish throat and light streaking on their undersides. Juveniles look similar to females, but are more heavily streaked with lighter bellies and light edging on their wing feathers. More

Brown-headed Cowbirds eat seeds from weedy plants, as well as insects, including grasshoppers, crickets, and beetles. They will also eat other small creatures they can catch, such as spiders. Copyright, Dan Sudia What this bird is best known for is its breeding habits. These birds do not build a nest or raise their young. Instead, after mating, female cowbirds lay their eggs in the nests of other birds. Then they fly away, never to return. More

Brown-headed Cowbirds, members of the Blackbird Family (Icteridae) that includes species such as Rusty Blackbirds, Common Grackles, and Red-winged Blackbirds. In winter, cowbirds often join other blackbirds in large flocks, moving through farmland and suburbia foraging on the ground for nuts, seeds, and invertebrates. As spring arrives, cowbird behavior changes dramatically. Females become elusive, while males (top, and above right) hang out in conspicuous small groups-vigorously displaying and calling to compete for a female's attention. More

Brown-headed Cowbirds arrive at our location around May 1. We typically see 2 males and 1 female when they arrive. If you are interested in reading more about these birds, there is a very interesting essay entitled Cowbirds. The following is a small sample of information from this essay: A female Brown-headed Cowbird has a long reproductive period with an extraordinarily short interval between clutches. More

DESCRIPTION: Brown-headed Cowbird is relatively small, with short and conical bill, rather long and pointed wings, and slightly rounded tail. Adult male is uniformly glossy greenish back, with brown head and neck. It has black eyes, legs and feet. The bill is dull grey. Adult female is brownish grey above, with a faint greenish gloss. The wings and tail are more dusky brownish, with pale feather edges. Chin and throat are paler, sometimes almost white. Female is smaller than male. More

The Brown-headed Cowbird is native to North America and the Caribbean. It can be found in the United Kingdom and Belize as well. This bird has a range reaching up to 11 million square kilometers. The estimated population of this bird is extensive, believed to be around 56 million individual birds. In 2000, the evaluation of this bird was changed from Lower Risk to Least Concern as a result of his extensive population and range. More

Brown-headed cowbirds are now found across most of North America. They are usually in deciduous forests, forest edge and grassland. See BBS map. Bronzed cowbirds tend to be in partially open habitats with scattered trees or scrub and pastures. They are only found in the arid southwest. See BBS map. (The rest of the information on this page focused on Brown-headed cowbirds since they are more widespread. More

Female Brown-headed Cowbirds perform some of the same displays as males of the species. Females tend to be “sneaky” when searching for host nests, skulking quietly through the undergrowth or canopy leaves. A female Brown-headed Cowbird often locates a potential host nest during its construction phase. She then regularly visits the nest prior to laying while the host species are absent. More

decline of the Brown-headed Cowbird in this region (-5.6, p=0.00 Trend Graph S28), as is the case in the Great Lakes Transition region (-2.4, p=0.00 Trend Graph S20). Survey-wide (US and Canada), this species has shown a slight but significant decline (-1.0, p=0.00 Trend Graph SUR). More

Habitat: Brown-headed cowbirds can be found flying along agricultural lands, fields, woodland edges and suburban areas. Nesting: The cowbird lays four or five white eggs, lightly speckled with brown or gray. They do not build nests. Bird Bite: Referred to as brood parasites, brown-headed cowbirds lay their clutch in the nests of other birds. More

Brown-headed cowbirds can be found year-round in the western U.S., and much of eastern U.S. Their summer range extends up into Canada. They like riversides, wood edges, fields, pastures, and suburbs. In winter, Brown-headed cowbirds may join large flocks with several blackbird species. Breeding and Nesting - Males gather in small flocks to do courtship displays where they sing with their wings, and tail spread while fluffing their feathers to attract females. More