Monday, January 17, 2011

Black Vulture

The gregarious black vulture roosts, feeds, and soars in groups, often mixed with turkey vultures. A carrion feeder that will bully a turkey vulture away from a carcass, it occasionally kills smaller live prey. Polytypic (3 ssp.; nominate in North America). Length 25" (64 cm); wingspan 57" (145 cm).

Identification Adult: glossy black feathers can show iridescence in the right light. Whitish inner primaries often hard to see on the folded wing. Whitish legs contrast with dark gray head color. Skin of head wrinkled; bill dark at base and tipped ivory or yellowish. Juvenile: black body and wing feathers usually duller, less iridescent. Skin of head smooth, darker black than an adult. Flight: conspicuous white or silvery patches at base of primaries that contrast with black wings, body, and tail. Whitish legs extend almost to tip of relatively short tail. Soars and glides with wings held in a slight dihedral. If seen at a distance, the quick, shallow, choppy wingbeats interspersed with glides are usually enough for an identification.

Similar Species The turkey vulture shows silvery inner secondaries and a pronounced dihedral while in flight, along with a deeper, more fluid wingbeat.
Voice Hisses when threatened.

Status and Distribution Abundant in the Southeast, expanding up the East Coast into southern New England. Less common in southern Great Plains, local in southern Arizona. Breeding: nests in a sheltered area on the ground, including abandoned buildings. Migration: sedentary, northern breeders, may migrate with turkey vultures to warmer winter territory. Vagrant: casual to California, northern New England, and southern Canada.
Population The species adapts well to human presence, feeding on roadkills and at garbage dumps.
—From the National Geographic book Complete Birds of North America, 2006