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The barren-ground caribou (''Rangifer tarandus groenlandicus'') is a subspecies of the caribou that is found mainly in the Canadian territories of Nunavut and the Northwest Territories, along with western Greenland. It sometimes includes the similar Porcupine caribou, in which case the barren-ground caribou is also found in Alaska.〔Cronin, M. A., M. D. Macneil, and J. C. Patton (2005). ''Variation in Mitochondrial DNA and Microsatellite DNA in caribou (Rangifer tarandus) in North America.'' Journal of Mammalogy 86(3): 495–505.〕 The barren-ground caribou is a medium-sized caribou, smaller and lighter coloured than the boreal woodland caribou, with the females weighing around and the males around . However, on some of the smaller islands, the average weight may be less. == Range and population == In Canada about fifty percent of all caribou are barren-ground caribou.〔 Like the Peary caribou, both the males and females have antlers. In general, during the summer, the coat of the caribou is brown, and much lighter in the winter. The neck and rump tends towards a creamy-white colour. However, the general colouration may differ depending on the region. The barren-ground caribou usually breeds in the fall and calves in June but may not drop their single calf until July. Usually the female gives birth away from the herd and if possible on a patch of snow. After birth, the female licks the calf clean and eats the tissues and the placenta. This may serve two purposes, to replace nutrients lost from birthing and to help remove the scent that would attract predators. The main food source is lichen but they also feed on Cyperaceae (sedges) and other grasses along with twigs and mushrooms. Caribou have also been observed to eat antlers and seaweed and to lick salt deposits. There is some evidence to suggest that on occasion they also feed on lemmings, Arctic char and bird eggs. On the mainland of Canada, the animals may travel in herds of several thousand, but they move in smaller groups (no more than 50) on the islands. They are migratory animals and may travel in a season. Some groups, such as those living on Victoria Island during the summer, migrate to the mainland in the fall after the sea ice has formed. At this time, the smaller groups may form into a larger herd and several hundred animals may be seen. Mainland barren-ground caribou herds move to coastal areas for part of each year, with the exception of the Beverly Herd.〔(【引用サイトリンク】title=The Beverly Caribou Herd: Continental Wilderness Travellers )〕 The Beverly Herd (located primarily in Saskatchewan, Northwest Territories; portions in Nunavut, Manitoba, Alberta) and the Qamanirjuaq Herd (located primarily in Manitoba, Nunavut; portions in southeastern NWT, northeastern Saskatchewan) fall under the auspices of the Beverly and Qamanirjuaq Caribou Management Board. The range of the Beverly herd spans the tundra from northern Manitoba and Saskatchewan and well into the Northwest Territories and Nunavut. In 1994 survey there were 276,000 caribou, an all-time record. According to a 2011 survey based on data collected using cutting-edge digital tools and fly-over visual surveillance, there were approximately 124,000 caribou in the Beverly herd and 83,300 in the Ahiak herd. The calving grounds of the Beverly caribou herd are located around Queen Maud Gulf but the herd shifted its traditional birthing area. Ross Thompson, executive director of the Beverly and Qamanirjuaq Caribou Management Board, explains the low calving rate mainly on habitat deterioration and disturbance with other factors contributing to the low growth rate – parasites, predation and poor weather.〔 John Nagy, University of Alberta's wildlife biologist and researcher, argued that the Beverly herd was robust not declining. He claimed the herd had moved their calving grounds "near the western Queen Maud Gulf coast to the north of the herd’s “traditional” calving ground in the Gary Lakes area north of Baker Lake." He based his findings on data collected from 510 barren-ground caribou tracked with satellite collars in the Northwest Territories and Nunavut from 1993 to 2009. The barren-ground caribou, one of several subspecies called ''tuktu'' in Inuinnaqtun/Inuktitut, and written as ''ᓇᐹᕐᑐᕐᑲᓐᖏᑦᑐᒥ ᑐᒃᑐ''〔Terrestrial Mammals of Nunavut by Ingrid Anand-Wheeler. ISBN 1-55325-035-4〕 in Inuktitut syllabics, is a major food source for the Inuit, especially the Caribou Inuit bands living in the Kivalliq Region (''Barren Lands'') of present-day Nunavut.〔(【引用サイトリンク】title=Walking on the Land )〕 The major predator of barren-ground caribou is the Arctic wolf. Wolves may follow the herd for many miles. The caribou has poor eyesight and hearing but is capable of outrunning the wolf. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Barren-ground caribou」の詳細全文を読む スポンサード リンク
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