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The boreal woodland caribou also known as woodland caribou, woodland caribou (boreal group), forest-dwelling caribou, ''Rangifer tarandus'' caribou.〔Bergerud 1988, used the general ecotypes migratory and sedentary, based on calving strategies, to distinguish the Holarctic migratory tundra caribou/reindeer which were thriving in 1988 with a population of three million in North America, from the declining population of sedentary caribou in both Eurasia and North America that numbered about 325,000 in 1988 (Bergerud 1988). Since then migratory caribou have also experienced declines in their numbers.〕 Boreal woodland caribou—are mainly but not always—sedentary.〔In their 2012 report entitled "Recovery Strategy for the Woodland Caribou (Rangifer tarandus caribou), Boreal population, in Canada", Environment Canada and SARA refer to the woodland caribou as "boreal caribou". "Woodland Caribou (Rangifer tarandus caribou), Boreal population herein referred to as "boreal caribou", assessed in May 2002 as threatened by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).〕 The woodland caribou is the largest of the caribou subspecies and is darker in colour than the barren-ground caribou. Valerius Geist, specialist on large North American mammals, described the "true" woodland caribou as "uniformly dark, small-manned type with the frontally emphasized, flat-beamed antlers", which is "scattered thinly along the southern rim of North American caribou distribution" has been incorrectly classified. He affirmed that "true woodland caribou is very rare, in very great difficulties and requires the most urgent of attention." The national meta-population of this sedentary boreal ecotype spans the boreal forest from the Northwest Territories to Labrador. They prefer lichen-rich mature forests and mainly live in marshes, bogs, lakes, and river regions. The historic range of the boreal woodland caribou covered over half of present-day Canada, stretching from Alaska to Newfoundland and Labrador and as far south as New England, Idaho, and Washington. Woodland caribou have disappeared from most of their original southern range. The boreal woodland was designated as threatened in 2002 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Environment Canada reported in 2011 that there were approximately 34,000 boreal caribou in 51 ranges remaining in Canada.(Environment Canada, 2011b). In a joint report by Canadian Parks and Wilderness Society (CPAWS) and the David Suzuki Foundation, on the status of woodland caribou, claim that "the biggest risk to caribou is industrial development, which fragments their habitat and exposes them to greater predation. Scientists consider only 30% (17 of 57) of Canada’s boreal woodland caribou populations to be self-sustaining." "They are extremely sensitive to both natural (such as forest fires) and human disturbance, and to habitat damage and fragmentation brought about by resource exploration, road building, and other human activity. New forest growth following destruction of vegetation provides habitat and food for other ungulates, which in turn attracts more predators, putting pressure on woodland caribou." Compared to barren-ground caribou or Alaskan caribou, boreal woodland caribou do not form large aggregations and are more dispersed particularly at calving time. Their seasonal movements are not as extensive. Mallory and Hillis explained how, "In North America populations of the woodland caribou subspecies typically form small isolated herds in winter but are relatively sedentary and migrate only short distances (50 - 150 km) during the rest of the year." The name caribou was probably derived from the Mi'kmaq word ''xalibu'' or ''Qalipu'' meaning "the one who paws."〔Caribou was introduced into the French language by Marc Lescarbot in his publication (1610 ). Silas Tertius Rand included the term Kaleboo in his Mi'kmaq-English (dictionary ) in 1888 (Rand 1888:98).〕 According to the then-Canadian Wildlife Service Chief Mammologist, Frank Banfield, the earliest record of ''Rangifer tarandus caribou'' in North America, is from a 1.6 million year old tooth found in the Yukon Territory. Other early records of caribou include a "45,500-year-old cranial fragment from the Yukon and a 40,600-year-old antler from Quebec." == Species and subspecies description == The reindeer species 'Rangifer tarandus', of which ''Rangifer tarandus caribou'' is a subspecies, is a medium-sized ungulate which inhabits boreal, montane, and arctic environments, and exhibits "tremendous variation in ecology, genetics, behaviour and morphology." Most of the subspecies, ''Rangifer tarandus caribou'' are now only found in Canada. A distinctive characteristic of all caribou is large crescent-shaped hooves that change shape with the season and that are adapted to walking in snow-covered and soft ground such as swamps and peat lands, and assist in digging through snow to forage on lichens and other ground vegetation. The subspecies ecotype, boreal woodland caribou, have a shoulder height of approximately 1.0-1.2 m shoulder height and weigh 110–210 kg. Both male and female boreal caribou have antlers during part of the year, although some females may have only one antler or no antlers at all (Boreal Caribou ATK Reports, 2010-2011). On the males these grow so quickly each year that velvety lumps in March can become a rack measuring more than a metre in length by August. Antlers of boreal caribou are flattened, compact, and relatively dense. Boreal caribou antlers are thicker and broader than those of the barren-ground caribou, and their legs and heads are longer. The boreal woodland Caribou is well-adapted to cold environments with a compact body covered with a thick and long coat (thicker in winter than in summer). They with a large blunt muzzle, short wide ears, and a small tail. Adults have a brown to dark-brown coat in summer, becoming greyer in winter. Adults have distinctive creamy white neck, mane, shoulder stripe, underbelly, underside of the tail, and patch above each hoof(Boreal Caribou ATK Reports, 2010-2011) 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「Boreal woodland caribou」の詳細全文を読む スポンサード リンク
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