[order] ACCIPITRIFORMES | [family] Accipitridae | [latin] Buteo hemilasius | [authority] Temminck and Schlegel, 1844 | [UK] Upland Buzzard | [FR] Buse de Chine | [DE] Mongolenbussard | [ES] Busardo mongol | [NL] Mongoolse Buizerd
Members of the genus Buteo are broad-winged, broad-tailed hawks, Well adapted for soaring. The bill, legs and talons are of average proportions. There is much colour variation both within the species, and, by way of phases, within individual species. In all cases the young are quite different from adults in that they are all well camouflaged with an overall brown appearance with varying amounts of striping below and paler mottling above.
The 25 species are spread worldwide with the exception of Australasia and much of the Indian sub-continent.
The adult Upland Buzzard has a light brown head with a broad brown moustachial streak. The head is edged with white, forming a white patch on its nape. The rest of its upper side, including upper-wing coverts, is light brown edged with pale rufous, the upper-tail coverts having a few white spots. The tail is brown, its central feathers being mottled along shafts with white and with two or three darker bars at the tip. The wing quills and outer primaries are black, with some white on the inner webs below the notch. The remainder are increasingly white, the outer webs being grey at the base. Both webs are barred with dark brown towards the tips. The chin is white. The throat and fore-neck are brown with white bases showing. The rest of the under side is rufous-white, including the under-wing coverts, which are rusty red and contrast strongly with pale wing quills. The upper breast, flanks and sides are blotched with brown, the thighs are brown with pale bars. The eyes are buff, white, or golden. The cere is greenish yellow, the legs and feet yellow to greyish yellow. The tarsus is partly feathered. This is a large buzzard, typically weighing between one and one and a half kilos (two kilos at fledging). A dark phase occurs which is dark chocolate brown throughout, the primaries showing only a little white on inner webs and, as is common in the genus, there are numerous intermediates between light and dark phases. Immatures are similar to the adult, but with the tail barred dark brown. Their eyes are brown; their cere greenish and their legs yellow. A very large buzzard, with the proportions of a fair-sized eagle. At rest the pale coloured head, and pale barred tail, distinguish it from the Common Buzzard (Buteo buteo) where their ranges overlap. In flight, the rusty-brown under-wing coverts, pale, barred wing quills, a broad dark trailing edge, and an almost white looking tail are good guides. There is a lot of variation among individuals, however, some being quite dark below with paler breasts.
|wingspan min.:||0||cm||wingspan max.:||0||cm|
|size min.:||66||cm||size max.:||71||cm|
|incubation min.:||28||days||incubation max.:||33||days|
|fledging min.:||42||days||fledging max.:||47||days|
Eurasia : East. The breeding range of the Upland Buzzard is in the high country of central Asia, overlapping in the west with the Long-legged Buzzard (Buteo rufinus). In winter it migrates to North India, Burma, Central China and Korea.
This species takes the place of the Long-legged Buzzard (Buteo rufinus) in the dry upland steppes of Tibet, South China, etc. It is most often seen in open steppes and wide valleys at high altitudes, or in mountainous country. In Tibet it has been seen at up to 15,000 feet (4570 metres), and is probably present even higher. Excepting on migration in winter, it is not seen in low-lying plains. It is found in steppe or open plains, mountains and desert throughout its range. In the breeding grounds a pair usually requires a territory of anything from 50-200 square kilometres, but in really suitable areas two pairs may breed only 50 metres apart. The population is controlled to some extent by available breeding sites, and is subject to irregular fluctuations connected with rodent cycles. In areas where pairs are widely separated the whole available range is probably not hunted.
Display is frequent and vigorous during the breeding season. The birds soar together, often descending gently with their wings held above their backs, and the male may dive at the female. Sometimes the two lock talons and come whirling down, separating near the ground. Mating takes place on the ground, the male balancing on the female’s back with flapping wings. The nest is built by the birds themselves, and is small and flattish, about one metre across, made of sticks and lined with grass, hair or wool. It is built on low crags, sometimes sheltered by bushes, or on the steep clay banks of rivers, and is frequently close to the nests of other birds of prey. Pairs often have more than one nest, which are used in rotation. Two to four eggs are laid in late April or May. If lost, clutches will often be replaced. The incubation period is about 30 days. The young hatch in May or June, and as they grow they often fight with one an other in the nest. Older nestlings sometimes kill the younger, and cannibalism is not unknown. They leave the nest in mid-July to early August, giving a fledging period of about 45 days. Generally speaking, two young are successfully reared per pair each year. They migrate to their winter quarters about one month to six weeks after leaving the nest.
The Upland Buzzard lives on a diet composed practically entirely of small ground mammals; also some ground birds such as larks and pipits, occasionally Ptarmigan. Like a Tawny Eagle, it will come to wounded birds, but does not take carrion. All prey is taken on the ground, generally very easily, by dropping on it from a perch or in flight.
Video Upland Buzzard
copyright: K. Blomerley
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be fluctuating, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size may be moderately small to large, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
Mostly migratory, with some birds perhaps wintering in or near breeding areas; generally avoids snow-covered areas. In China, winters mainly North of River Yangtze, occasionally further South, to Guangdong; records of 30 and 40 birds seen on consecutive days in Northwest Sichuan (Central China) in 1989; rare in winter on South slopes of Himalayas in North India and Nepal. Accidental to Japan, mainly in winter, almost certainly from Korea.
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