The Siberian crane (Leucogeranus leucogeranus), also known as the Siberian white crane or the snow crane, is a bird of the family Gruidae, the cranes. They are distinctive among the cranes: adults are nearly all snowy white, except for their black primary feathers that are visible in flight, and with two breeding populations in the Arctic tundra of western and eastern Russia. The eastern populations migrate during winter to China, while the western population winters in Iran and (formerly) in Bharatpur, India.
Among the cranes, they make the longest distance migrations. Their populations, particularly those in the western range, have declined drastically in the 20th century due to hunting along their migration routes and habitat degradation. The world population was estimated in 2010 at about 3,200 birds, mostly belonging to the eastern population with about 95% of them wintering in the Poyang Lake basin in China, a habitat that may be altered by the Three Gorges Dam.
Adults of both sexes have a pure white plumage except for the black primaries, alula and primary coverts. The fore-crown, face and side of head is bare and brick red, the bill is dark and the legs are pinkish. The iris is yellowish. Juveniles are feathered on the face and the plumage is dingy brown. There are no elongated tertial feathers as in some other crane species. During breeding season, both the male and female cranes are often seen with mud streaking their feathers. They dip their beaks in mud and smear it on their feathers. The call is very different from the trumpeting of most cranes and is a goose-like high pitched whistling toyoya. This is a fairly large species of crane. Siberian cranes typically weigh 4.9–8.6 kg (11–19 lb) and stand about 140 cm (4 ft 7 in) tall. The wingspan is reportedly from 210 to 260 cm (6 ft 11 in to 8 ft 6 in) and length is 115–127 cm (45–50 in). Males are on average larger than females. The average weight of adults in one study was 6.81 kg (15.0 lb) while juvenile birds were slightly heavier on average at 7.1 kg (16 lb). There is a single record of an outsized male of this species weighing 15 kg (33 lb). Usually, this crane is usually slightly smaller in weight and height than some other cranes, particularly the sarus crane, wattled crane and red-crowned crane.
Siberian cranes return to the Arctic tundra around the end of April and beginning of May. The nest is usually on the edge of lake in boggy ground and is usually surrounded by water. Most eggs are laid in the first week of June when the tundra is snow free. The usual clutch is two eggs, which are incubated by the female after the second egg is laid. The male stands guard nearby. The eggs hatch in about 27 to 29 days. The young birds fledge in about 80 days. Usually only a single chick survives due to aggression between young birds. The population increase per year is less than 10%, the lowest recruitment rate among cranes. Their success in breeding may further be hampered by disturbance from reindeer and sometimes dogs that accompany reindeer herders. Captive breeding was achieved by the International Crane Foundation at Baraboo after numerous failed attempts. Males often killed their mates and captive breeding was achieved by artificial insemination and the hatching of eggs by other crane species such as the Sandhill and using floodlights to simulate the longer day lengths of the Arctic summer.
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