Caribou herds in Canada are discrete populations of seven subspecies that are represented in Canada. Caribou can be found from the High Arctic region south to the boreal forest and Rocky Mountains and from the east to the west coasts.
Arctic peoples, including the Caribou Inuit, the inland-dwelling Inuit of the Kivalliq Region in northern Canada, the Caribou Clan in Yukon, the Iñupiat, the Inuvialuit, the Hän, the Northern Tutchone, and the Gwich'in, who followed the Porcupine caribou (also known as Grant's caribou) for millennia, have depended on caribou for food, clothing, and shelter.;;
COSEWIC divided caribou ecotypes in Canada into 12 "designatable units" (DU), an adaptation of "evolutionarily significant units", for purposes of conservation and monitoring that, for the most part, follow previously named species and subspecies (see Caribou Subspecies below). They are: Peary DU1, Dolphin and Union DU2, Barren-Ground DU3, Eastern Migratory DU4, Newfoundland DU5, Boreal DU6, Northern Mountain DU7, Central Mountain DU8, Southern Mountain DU9, Torngat Mountains DU10, Atlantic-Gaspésie DU11, and the extinct Dawson's DU12.
The responsibility for the management and monitoring of herds is often shared between Inuit, Métis, and First Nations communities, local hunter and trapper associations, territorial and provincial governments, and the federal government.
Based on the most recent 10-year long assessment of caribou populations in Canada, every designated unit of caribou across the country, is in "some kind of danger." More than half of the DUs were endangered. In 2018, vast herds that used to be numbered in the millions, and were not in danger 15 years ago, are now threatened and scientists have recommended that the eastern migratory caribou be listed as endangered, "the highest level of threat".
Caribou subspecies
Current classification These subspecies are recognized internationally (before a recent revision; see below): In North America, R. t. caboti, R. t. caribou, R. t. dawsoni, R. t. groenlandicus, R. t. osborni, R. t. pearyi, and R. t. terranovae; and in Eurasia R. t. tarandus, R. t. buskensis (called R. t. valentinae in Europe; see below), R. t. phylarchus, R. t. pearsoni, R. t. sibiricus and R. t. platyrhynchus.
Grant's caribou, originally R. granti Allen,Allen JA (1902) A new caribou from the Alaska Peninsula. Bulletin of the American Museum of Natural History XVI: 119-127. was described as a small, pale form endemic to the west end of the Alaska Peninsula and nearby islands. It was later brought under Arctic caribou (Rangifer arcticus Richardson 1829) as R. a. granti with the same limited distribution.Osgood WH (1909) Biological investigations in Alaska and Yukon Territory. US Department of Agriculture Biological survey of North American fauna 1: 1-285.Murie OJ (1935) Alaska-Yukon caribou. Vol. 54, United States Department of Agriculture Bureau of Biological Survey, Washington D.C.Anderson RM (1946) Catalogue of Canadian Recent mammals. National Museum of Canada Bulletin No. 102, Biological Series 31, Ottawa, Ontario. initially kept Allen's R. a. granti as restricted to the Alaska Peninsula and archipelago, but later extended it to all Alaskan caribou (except stonei, the montane ecotype) including the former R. ogilviensis (the Porcupine herd). But granti was never accepted internationally as a subspecies of barren-ground caribou, and Youngman (1975) assigned the Porcupine herd (and by inference, all four Alaskan tundra herds) to barren-ground caribou, R. t. groenlandicus.Youngman PM (1975) Mammals of the Yukon Territory. National Museum of Canada, Publications in Zoology No. 10
also synonymized stonei Allen JA (1901) Description of a new caribou from Kenai Peninsula, Alaska. Bulletin of the American Museum of Natural History XIV: 143-148. with subspecies of woodland caribou, R. t. caribou.
2022 revision Since 1986,Røed KH, Whitten KR (1986) Transferrin variation and evolution of Alaskan reindeer and caribou, Rangifer tarandus L. Rangifer Special Issue 1: 247-251. nearly four decades of genetic analysis of Rangifer populations using nuclear DNA and mitochondrial DNA (mtDNA) have reported caribou and reindeer population genetics. They have revealed diversity at the species and subspecies level that was not recognized by taxonomic authorities since revisions in the mid-20th Century (see Reindeer: Taxonomy). Genetic data were brought together with morphological, ecological, behavioral and archaeological data, resulting in a new revision of Rangifer. Major changes for caribou in Canada were: (1) resurrection of previous names for Arctic and Woodland caribou; (2) woodland caribou diverged from other species of Rangifer not by isolation in the last glacial maximum (LGM) but deep in the Pleistocene about 357,000 years ago; (3) Canadian barren-ground caribou and Eurasian tundra reindeer, although both of recent (late Pleistocene) Beringian-Eurasian ancestry, clustered separately with genetic distance, private vs. shared haplotypes and alleles indicating they are distinct species; (4) the four western montane ecotypes in Canada and Alaska that had been subsumed under woodland caribou were found to be of Beringian-Eurasian ancestry, but distantly (they diverged > 60,000 years ago, before modern tundra reindeer/barren-ground caribou had evolved; see Reindeer: Evolution), (5) the extinct Dawson caribou is also of Beringian-Eurasian ancestry, (6) R. a. granti was rediscovered when specimens from the original, limited range were found to cluster genetically apart from all other Alaskan caribou,Mager KH, Colson KE, Groves P, Hundertmark KJ (2014) Population structure over a broad spatial scale driven by nonanthropogenic factors in a wide-ranging migratory mammal, Alaskan caribou. Molecular Ecology 23: 6045-6057. with no interbreeding with nearby ecotypes.Colson KE, Mager KH, Hundertmark KJ (2014) Reindeer introgression and the population genetics of caribou in southwestern Alaska. Journal of Heredity 105: 585-596. (7) Stone's caribou, R. a. stonei, was confirmed as of Beringian-Eurasian ancestry, but clusters apart from osborni, granti, and arcticus; resulting in resurrection of this subspecies.
The Porcupine caribou herd of barren-ground caribou, named for a river that flows from Yukon into Alaska, was originally named R. ogilviensis Millais, 1915 for its winter range in the Ogilvie mountains, but morphological and genetic analyses showed it to be nearly indistinguishable from other barren-ground caribou; after the revision, it reverted to R. arcticus arcticus.
In the new taxonomy, nine subspecies of Rangifer are represented in Canada, most of which line up with COSEWIC's designatable units. Woodland caribou, R. caribou, has three subspecies: the nominate subspecies, boreal woodland caribou DU6, (R. c. caribou), Labrador caribou DU4, (R. c. caboti), and Newfoundland caribou DU5 (R. c. terraenovae). Arctic caribou, R. arcticus, has eight living subspecies and one extinct in Canada: the nominate subspecies, barren-ground caribou DU3, R. a. arcticus; Peary caribou DU1 (R. a. pearyi); Osborn's caribou "Northern Mountain" DU7, R. a. osborni; Rocky Mountain caribou "Central Mountain" DU8, R. a. fortidens; and Mountain caribou "Southern Mountain population of southern mountain caribou" DU9, R. a. montanus; and the extinct Dawson's caribou DU12 of Haida Gwaii, R. a. dawsoni. The Dolphin and Union "herd" DU2, is a unique and genetically distinct ecotype of barren-ground caribou, R. a. arcticus, that migrates from winter range on the Barrenlands across Dolphin and Union Strait; it should probably be a named subspecies of R. arcticus but has not been formally described. Likewise, the Atlantic-Gaspésie caribou DU11 is genetically distinct enough for subspecies designation but has not been described. The Torngat Mountains caribou DU10 is a non-migratory ecotype of Labrador caribou, R. c. caboti. The above caribou names and those in following sections reflect a recent revision, but may not be in common use until international organizations adopt the new taxonomy.
Four subspecies are found in Inuit Nunangat.
For purposes of management and conservation, caribou populations are further divided into the boreal population in Yukon, Northwest Territories, British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, Quebec, Newfoundland and Labrador which includes the George River caribou and the Leaf River caribou, the Atlantic-Gaspésie caribou population in Quebec, the Dolphin-Union caribou in the Northwest Territories and Nunavut, the barren-ground population in Yukon, Northwest Territories, Nunavut, Alberta, Saskatchewan, and Manitoba which includes the large migratory herds such as the Ahiak herd, the Baffin Island herds, the Bathurst herd, the Beverly herd (Beverly Lake in western Nunavut),The Beverly Caribou Herd's headlong rush to extinction February 22, 2016 Don Jaque the Bluenose East herd (southwest of Kugluktuk), the Bluenose West herd, the Porcupine herd, the Qamanirjuaq herd, Lorillard herd, Wager Bay herd, Pen Islands herd, Cape Churchill herd, Southampton Island Herd, and Tuktoyaktuk Peninsula Herd. Porcupine caribou herd, Bluenose west herd, and the Dolphin Union herd, the Central Mountain population in British Columbia and Alberta, the Southern Mountain population in British Columbia, the Eastern Migratory population of Manitoba, Ontario, Quebec, Newfoundland and Labrador, and the Torngat Mountains population of Nunavut, Quebec, Newfoundland and Labrador, the Newfoundland population in Newfoundland and Labrador and the Northern Mountain population in Yukon, Northwest Territories, and British Columbia, Eastern Migratory in Newfoundland, Northern Mountain in British Columbia, Dolphin and Union, and Peary caribou.
In the following sections, to avoid confusion, Latin name reflect the international consensus before the recent revision.
Woodland caribou, R. t. caribou
Boreal woodland The boreal forest of Canada is the vital habitat of the endangered subspecies, the boreal caribou. The survival of boreal caribou depends on maintaining "large unbroken swaths" of the forest to protect the animals from their predators. The boreal forest—which is not monolithic but a patchwork—sweeps through parts of all provinces and territories except Nova Scotia and Prince Edward Island. It covers approximately 25% of Canada's total landmass——and consists of "swamps, bogs, meadows, forests of different types — including hardwoods and conifers — and the rivers and lakes that tie them all together". It represents 75 per cent of the nation's forests.
The boreal woodland caribou are half again the size (males average 180 kg, up to 272 kg) of barren-ground caribou (males average 110 kg, up to 153 kg) and smaller than the three western montane ecotypes. They have dark colored fur (only the Selkirk mountain caribou is darker) and their boreal forest habitat stretches from Newfoundland to British Columbia in an irregular distribution. Most boreal woodland caribou are not migratory. The Labrador caribou, which interbred in ancient times with barren-ground caribou, migrate long distances, while and the Torngat Mountains population of Nunavut, Quebec, Newfoundland and Labrador, and the Atlantic-Gaspésie caribou, move with the seasons to different elevations.