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, was described as a small, pale form endemic to the west end of the
Alaska Peninsula and nearby islands. 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, also synonymized
stonei with subspecies of woodland caribou,
R. t. caribou.
2022 revision Since 1986, 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, with no interbreeding with nearby ecotypes. (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. 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. 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. This includes the spatial configuration, quantity, quality of habitat that local population need to survive. In 2008, there were "57 recognized local populations or units of analysis for Boreal caribou in Canada." The George River caribou are one of four subpopulations of Labrador caribou in
northern Canada. The herd's range extends through Labrador and Northern Quebec (Labrador Woodland Caribou Recovery Team, 2004). In southern Labrador and northeastern Quebec, the range of three herds of the sedentary boreal woodland caribou,
R. t. caribou, the Lac Joseph herd (LJH) , the Red Wine Mountains herd (RWMH) , and the
Mealy Mountains herd (MMH) is bounded on the north by the George River herd. In the winter the multiple herds intermingle when the George River herd enters the outer portions of the sedentary caribou ranges. In 2014, COSEWIC assessed the status of Newfoundland caribou as Special Concern.
Barren-ground caribou, R. t. groenlandicus The most abundant caribou with are the migratory barren-ground caribou which consist of huge herds that migrate annually to and from their natal grounds taking routes that are usually predictable. Because they migrate to the tundra, both the Leaf River herd and
George River herd have sometimes been included with the barren-ground caribou, but genetic and other data show them to be woodland caribou that acquired some barren-ground caribou genes early in the Holocene (see
Reindeer: Taxonomy).
Bluenose East-Bathurst caribou The Bluenose East-Bathurst caribou, (southwest of
Kugluktuk), are cross-border caribou herds, with migrations that bring them into both
Nunavut and the
Northwest Territories. In 2016, the Nunavut Wildlife Management Board with the endorsement of the Government of Nunavut developed a "community-based caribou plan" for
Kugluktuk that limited harvest to 340 caribou. In 2019, government representatives from
Nunavut, the
Northwest Territories, Kugluktuk MLA Mila Kamingoak, biologists from the Nunavut and N.W.T., representatives from N.W.T. First Nations groups, Nunavut hunters and trappers organizations including Kugluktuk Hunters and Trappers Organization (HTO) worked together to improve management of the Bluenose East-Bathurst caribou herds. In 2016, although both Nunavut and N.W.T. governments opposed mining exploration on Bluenose East caribou calving grounds, the project went ahead. The Bathurst caribou herd has suffered a dramatic decline from a record number of about 470,000 in the mid-1980s to only 8,200 in 2018. By 2003 there were 186,000 and by 2009 there were 32,000. "Between 2015 and 2018, the number of breeding cows dropped by almost 40 per cent to about 3,000 animals." In 2019, the governments of Canada and the Northwest Territories pledged $61 million towards the construction of a 640 kilometre-long road "connecting Yellowknife to the Arctic Coast to open up mining in the Arctic". The
Bureau of Land Management (BLM) draft 2018 Environmental Impact Statement (EIS) said that in order to reduce the vulnerability of the Porcupine Caribou Herd (PCH) and Central Arctic Herds (CAH) adaptive mitigation had to be undertaken in "[a]ll lands in the Arctic Refuge Coastal Plain are recognized as habitat of the PCH and CAH and would be managed to ensure unhindered movement of caribou through the area." Caribou calves are born in the first week of June and they are at their most vulnerable from their primary predators on the calving ground – golden eagles, grizzly bears and wolves – during the first three weeks when they are dependent on milk from their mothers. About one quarter of them die during this period. In February 2019, veteran researchers Don Russell and Anne Gunn, submitted their commissioned report to the Governments of Canada, Yukon Territory and the Northwest Territories—signatories to the 1987 International Treaty for the Porcupine herd. They undertook a "science-based risk assessment for how vulnerable the Porcupine Caribou herd (PCH)" is to the proposed oil and gas development of 1002 lands (Coastal Region) in the Alaska National Wildlife Refuge." Porcupine caribou's annual land migration between their winter range in the boreal forests of Alaska and northwest Canada over the mountains to the coastal plain and their calving grounds on the
Beaufort Sea coastal plain, The herd's annual range is contained within the
Arctic National Wildlife Refuge, established in 1980 by the US Congress. The Alaska National Interest Lands Conservation Act (ANILCA) included Section 1002 which "identified a need to assess the oil and gas potential as well as the wildlife values". The 1.57 million acres Coastal Plain had not been included in the ANWR's wilderness designation. In this report we refer to the area covered by Section 1002 of ANILCA as "1002" lands. Southampton Island caribou numbers "declined from about 30,000 caribou in 1997 to 7,800 caribou in 2011, representing a drop of almost 75%." In July 2012, the Government of Nunavut set an "annual harvest limit of 1,000 caribou" in response to an urgent request from the Coral Harbour Hunters and Trappers Organization (HTO). The hunt has become unsustainable as orders for caribou from the island was being flown as country food to places like Iqaluit. It is Designated Unit (DU) 9 in COSEWIC assignment of ecotypes. The cross boundary South Selkirk mountain caribou, of distant Beringian-Eurasian lineage (see above), had roamed the southern end of the
Selkirk Mountains crossing the border between
British Columbia, Canada and northern
Idaho, eastern
Washington, in the United States. They were the last naturally occurring caribou herd in the
contiguous United States. In 2009 the herd of 50 animals was declining, by April 2018, only three remained, Meanwhile, the Revelstoke maternity pen, beset with adult and calf mortality, was closed the same year and remaining animals moved to another temporary holding facility. In British Columbia "Herd plans are currently being developed for each of the 54 herds in B.C." These plans include local populations of Selkirk Mountain caribou, Rocky Mountain caribou and Osborn's caribou. Three related western montane ecotypes that have been found to be of the Beringian-Eurasian lineage are Stone's caribou of Alaska and just into south-eastern Yukon; Osborn's caribou of northern British Columbia and southern Yukon (DU7 in COSEWIC parlance); and Rocky Mountain caribou of the east slope of the Rocky Mountains in British Columbia and Alberta (DU8) (originally described as
R. fortidens Hollister, 1912). Dawson's caribou of Haida Gwaii was also of the Beringian-Eurasian lineage. These were all formerly considered ecotypes of woodland caribou,
R. tarandus caribou. ==Herds==