Bronzed Cowbird

The Bronzed Cowbird is a medium-sized, stocky blackbird named for the greenish-bronze sheen of the male's plumage, which can appear almost black in poor light. Males have a distinctive ruff of elongated neck feathers that they can raise into a hackle, especially during display, along with striking bright-red eyes. Females are duller gray-brown with the same red eye, though in some southern populations female eye color can be brown.

Like all cowbirds, the Bronzed Cowbird is a brood parasite, laying its eggs in the nests of other songbirds rather than building its own nest or raising its young, a strategy tied to its historically nomadic, livestock-following lifestyle.

Key Field Marks

• Stocky build with a short tail and thick, conical bill
• Males: glossy greenish-black to bronze body plumage, raised neck ruff, bright red eyes
• Females: plainer gray-brown, smaller ruff, red eyes
• Short, squared tail compared to grackles

Similar Species

• Brown-headed Cowbird males have a contrasting brown head against a glossy black body and dark eyes, and lack the neck ruff.
• Brewer's Blackbird males have yellow (not red) eyes and lack the ruff.
• Great-tailed Grackle is much larger with a very long tail.

Habitat

Bronzed Cowbirds favor open country, including grasslands, pastures, agricultural fields, and suburban lawns, often near cattle or other grazing animals that stir up insects.

Range

Found from the southwestern and south-central United States (Arizona, Texas, and parts of the Gulf Coast) south through Mexico and Central America into northern South America.

Migration

Some northern populations are migratory, withdrawing from the northernmost parts of their U.S. range in winter, while southern populations are largely resident.

Behavior

Bronzed Cowbirds forage on the ground, often walking among grazing livestock or following farm machinery to catch flushed insects. Males display by fluffing the neck ruff, hovering briefly above a female, and singing.

Voice

The song is a series of harsh, creaky gurgles and squeaks; calls include sharp chattering notes.

Feeding

Primarily eats seeds and grain, supplemented with insects, especially during the breeding season.

Nesting & Breeding

As an obligate brood parasite, the Bronzed Cowbird builds no nest of its own. Females seek out the nests of other songbird species, particularly orioles and other icterids, and lay a single egg per host nest, leaving the host parents to incubate and raise the chick.