Cinereous Vulture

About the cinereous vulture

The cinereous vulture, also known as the black vulture, Eurasian black vulture, or monk vulture, is a very large raptor in the family Accipitridae found across much of temperate Eurasia. It is the largest Old World vulture and the largest member of its family, with a body length of 98 to 120 centimeters (39 to 47 inches), a wingspan of 2.5 to 3.1 meters (8 feet 2 inches to 10 feet 2 inches), and a maximum recorded weight of 12.5 kilograms (28 pounds). Males typically weigh 6.3 to 11.5 kilograms (14 to 25 pounds) and females 7.5 to 12.5 kilograms (17 to 28 pounds); unusually for a bird of prey, the sexes broadly overlap in size, and females are not uncommonly the heavier of the two. Body size increases from west to east across its range, with birds from Spain and southern France averaging about 10 percent smaller than those from Manchuria, Mongolia, and northern China.

The bird is distinctly dark, with blackish-brown plumage and a pale, finely down-covered head in adults; the skin of the head and neck is bluish-grey with a paler patch above the eye. It has brown eyes, a purplish cere, a blue-grey bill, and pale blue-grey legs, and from a distance flying birds can look entirely black. Its massive bill, among the largest of any living accipitrid, measures 8 to 9 centimeters (3.1 to 3.5 inches) along the exposed culmen. Broad wings with serrated leading edges, sometimes described as "barn door wings," give it a slow, buoyant flight with deep, heavy flaps when needed. Its closest relative is the lappet-faced vulture; together with the white-headed and red-headed vultures, the four have at times been grouped in a broader version of the genus Aegypius. Despite a superficial resemblance and shared name, it is only distantly related to the smaller American black vulture, which belongs to the separate New World vulture family Cathartidae.

Behavior and diet

The cinereous vulture is a largely solitary bird, more often found alone or in pairs than in the groups typical of many other Old World vultures, though small numbers — rarely up to 20, occasionally 30 to 40 in older reports — may gather at a large carcass. It feeds almost entirely on carrion, from large mammals to fish and reptiles, and its powerful bill lets it tear open tough hides and even break bones such as ribs to reach flesh, making it dominant over other scavengers, including Gyps vultures, bearded vultures, and ground predators like foxes. Diet varies by region: in Tibet it feeds on wild and domestic yaks, bharal, and other large mammals; in Mongolia, tarbagan marmots make up much of the diet; and in Iberia it once relied on European rabbit before disease collapsed that population, shifting its reliance to domestic sheep, pigs, and deer.

Breeding pairs return to nesting grounds from January to April depending on region, breeding in loose colonies with nests rarely shared in the same tree or rock formation. Nests, built of sticks and twigs in trees or occasionally on cliff ledges, are large — 1.45 to 2 meters (4 feet 9 inches to 6 feet 7 inches) across — and grow over years of reuse. Clutches typically contain a single egg, incubated for 50 to 62 days, with both parents sharing incubation and feeding the chick by regurgitation. Roughly 90 percent of eggs hatch successfully, and more than half of yearlings survive to adulthood. In Mongolia, chicks have been recorded growing from about 2 kilograms (4.4 pounds) at a month old to nearly 16 kilograms (35 pounds) shortly before fledging in early autumn — briefly heavier than their parents.

Range and habitat

The cinereous vulture's range extends from Spain and inland Portugal, with a reintroduced population in southern France, discontinuously through Greece, Turkey, and the central Middle East, and eastward through Afghanistan and northern India to central Asia, where it breeds in northern Manchuria, Mongolia, and Korea. It is generally a permanent resident, though hard winters push some birds to lower elevations and juveniles may move more widely as they mature; in the eastern part of its range, some northern birds migrate to southern Korea and China.

It favors hilly and mountainous country, especially dry, semi-open habitats such as high-altitude meadows, and forages for carrion across steppe, grassland, open woodland, and riparian terrain. In Europe, the Caucasus, and the Middle East it is typically found between 100 and 2,000 meters (330 to 6,560 feet) in elevation, while in Asia it ranges higher — from mountainous forest and shrubland at 800 to 3,800 meters to arid alpine meadows at 3,800 to 4,500 meters. One individual was recorded at 6,970 meters (22,870 feet) on Mount Everest, aided by a specialized blood protein that allows efficient oxygen uptake at high altitude.

Conservation status

The cinereous vulture is classified as Near Threatened by the IUCN. Individuals may live up to 39 years, although 20 years or less is more typical, and adults have few natural predators beyond occasional attacks by golden eagles or Eurasian eagle-owls on nestlings or older birds. As a carrion-feeder, the species plays an important ecological role by removing carcasses and reducing the spread of disease.