Reindeer
The reindeer or caribou[a] (Rangifer tarandus)[5] is a species of deer with circumpolar distribution, native to Arctic, subarctic, tundra, boreal, and mountainous regions of Northern Europe, Siberia, and North America.[2] It is the only representative of the genus Rangifer. More recent studies suggest the splitting of reindeer and caribou into six distinct species over their range.
For other uses, see Reindeer (disambiguation).
Reindeer occur in both migratory and sedentary populations, and their herd sizes vary greatly in different regions. The tundra subspecies are adapted for extreme cold, and some are adapted for long-distance migration.
Reindeer vary greatly in size and color from the smallest, the Svalbard reindeer (R. (t.) platyrhynchus), to the largest, Osborn's caribou (R. t. osborni). Although reindeer are quite numerous, some species and subspecies are in decline and considered vulnerable. They are unique among deer (Cervidae) in that females may have antlers, although the prevalence of antlered females varies by subspecies.
Reindeer are the only successfully semi-domesticated deer on a large scale in the world. Both wild and domestic reindeer have been an important source of food, clothing, and shelter for Arctic people from prehistorical times. They are still herded and hunted today.[6] In some traditional Christmas legends, Santa Claus's reindeer pull a sleigh through the night sky to help Santa Claus deliver gifts to good children on Christmas Eve.
Description
Names follow international convention[7][8] before the recent revision[9] (see Taxonomy below). Reindeer/caribou (Rangifer) vary in size from the smallest, the Svalbard reindeer (R. (t.) platyrhynchus), to the largest, Osborn's caribou (R. t. osborni). They also vary in coat color and antler architecture.
The North American range of caribou extends from Alaska through the Yukon, the Northwest Territories and Nunavut throughout the tundra, taiga and boreal forest and south through the Canadian Rocky Mountains.[10] Of the eight subspecies classified by Harding (2022) into the Arctic caribou (R. arcticus), the migratory mainland barren-ground caribou of Arctic Alaska and Canada (R. t. arcticus), summer in tundra and winter in taiga, a transitional forest zone between boreal forest and tundra; the nomadic Peary caribou (R. t. pearyi) lives in the polar desert of the High Arctic Archipelago and Grant's caribou (R. t. granti) lives in the western end of the Alaska Peninsula and the adjacent islands; the other four subspecies, Osborn's caribou (R. t. osborni), Stone's caribou (R. t. stonei), the Rocky Mountain caribou (R. t. fortidens) and the Selkirk Mountains caribou (R. t. montanus) are all montane. The extinct insular Queen Charlotte Islands caribou (R. t. dawsoni), lived on Graham Island in Haida Gwaii (formerly known as the Queen Charlotte Islands).
The boreal woodland caribou (R. t. caribou), lives in the boreal forest of northeastern Canada: the Labrador or Ungava caribou of northern Quebec and northern Labrador (R. t. caboti), and the Newfoundland caribou of Newfoundland (R. t. terranovae) have been found to be genetically in the woodland caribou lineage.[11][12]
In Eurasia, both wild and domestic reindeer are distributed across the tundra and into the taiga. Eurasian mountain reindeer (R. t. tarandus) are close to North American caribou genetically and visually, but with sufficient differences to warrant division into two species. The unique, insular Svalbard reindeer inhabits the Svalbard Archipelago. The Finnish forest reindeer (R. t. fennicus) is spottily distributed in the coniferous forest zones from Finland to east of Lake Baikal: the Siberian forest reindeer (R. t. valentinae, formerly called the Busk Mountains reindeer (R. t. buskensis) by American taxonomists) occupies the Altai and Ural Mountains.
Male ("bull") and female ("cow") reindeer can grow antlers annually, although the proportion of females that grow antlers varies greatly between populations.[7] Antlers are typically larger on males. Antler architecture varies by species and subspecies and, together with pelage differences, can often be used to distinguish between species and subspecies (see illustrations in Geist, 1991[13] and Geist, 1998).[14]
Status
About 25,000 mountain reindeer (R. t. tarandus) still live in the mountains of Norway, notably in Hardangervidda.[15] In Sweden there are approximately 250,000 reindeer in herds managed by Sami villages.[16] Russia manages 19 herds of Siberian tundra reindeer (R. t. sibiricus) that total about 940,000.[17] The Taimyr herd of Siberian tundra reindeer is the largest wild reindeer herd in the world,[18][19] varying between 400,000 and 1,000,000; it is a metapopulation consisting of several subpopulations — some of which are phenotypically different[20] — with different migration routes and calving areas.[21][22] The Kamchatkan reindeer (R. t. phylarchus), a forest subspecies, formerly included reindeer west of the Sea of Okhotsk which, however, are indistinguishable genetically from the Jano-Indigirka, East Siberian taiga and Chukotka populations of R. t. sibiricus.[23] Siberian tundra reindeer herds have been in decline but are stable or increasing since 2000.[17]
Insular (island) reindeer, classified as the Novaya Zemlya reindeer (R. t. pearsoni) occupy several island groups: the Novaya Zemlya Archipelago (about 5,000 animals at last count, but most of these are either domestic reindeer or domestic-wild hybrids), the New Siberia Archipelago (about 10,000 to 15,000), and Wrangel Island (200 to 300 feral domestic reindeer).[24]
What was once the second largest herd is the migratory Labrador caribou (R. t. caboti)[9] George River herd in Canada, with former variations between 28,000 and 385,000. As of January 2018, there are fewer than 9,000 animals estimated to be left in the George River herd, as reported by the Canadian Broadcasting Corporation.[25] The New York Times reported in April 2018 of the disappearance of the only herd of southern mountain woodland caribou in the contiguous United States, with an expert calling it "functionally extinct" after the herd's size dwindled to a mere three animals.[26] After the last individual, a female, was translocated to a wildlife rehabilitation center in Canada, caribou were considered extirpated from the contiguous United States.[27] The Committee on Status of Endangered Wildlife in Canada (COSEWIC) classified both the Southern Mountain population DU9 (R. t. montanus) and the Central Mountain population DU8 (R. t. fortidens) as Endangered and the Northern Mountain population DU7 (R. t. osborni) as Threatened.[28]
Some species and subspecies are rare and three subspecies have already become extinct: the Queen Charlotte Islands caribou (R. t. dawsoni) from western Canada, the Sakhalin reindeer (R. t. setoni) from Sakhalin and the East Greenland caribou from eastern Greenland,[29][30][31] although some authorities believe that the latter, R. t. eogroenlandicus Degerbøl, 1957, is a junior synonym of the Peary caribou.[32][33][9] Historically, the range of the sedentary boreal woodland caribou covered more than half of Canada[34] and into the northern states of the contiguous United States from Maine to Washington. Boreal woodland caribou have disappeared from most of their original southern range and were designated as Threatened in 2002 by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).[35] Environment Canada reported in 2011 that there were approximately 34,000 boreal woodland caribou in 51 ranges remaining in Canada (Environment Canada, 2011b),[36] although those numbers included montane populations classified by Harding (2022) into subspecies of the Arctic caribou.[9] Siberian tundra reindeer herds are also in decline, and Rangifer as a whole is considered to be Vulnerable by the IUCN.
Naming
Charles Hamilton Smith is credited with the name Rangifer for the reindeer genus,[37] which Albertus Magnus used in his De animalibus, fol. Liber 22, Cap. 268: "Dicitur Rangyfer quasi ramifer". This word may go back to the Sámi word raingo.[38] Carl Linnaeus chose the word tarandus as the specific epithet, making reference to Ulisse Aldrovandi's Quadrupedum omnium bisulcorum historia fol. 859–863, Cap. 30: De Tarando (1621). However, Aldrovandi and Conrad Gessner[39] thought that rangifer and tarandus were two separate animals.[40] In any case, the tarandos name goes back to Aristotle and Theophrastus.
The use of the terms reindeer and caribou for essentially the same animal can cause confusion, but the International Union for Conservation of Nature clearly delineates the issue: "Reindeer is the European name for the species of Rangifer, while in North America, Rangifer species are known as Caribou."[2][41] The word reindeer is an anglicized version of the Old Norse words hreinn (“reindeer”) and dýr (“animal”) and has nothing to do with reins.[42] The word caribou comes through French, from the Mi'kmaq qalipu, meaning "snow shoveler", and refers to its habit of pawing through the snow for food.[43]
Because of its importance to many cultures, Rangifer and some of its species and subspecies have names in many languages. Inuvaluit of the western Canadian Arctic and Inuit of the eastern Canadian Arctic, who speak different dialects of Inuktitut, both call the barren-ground caribou tuktu.[44][45][46] The Wekʼèezhìi people, a Dene (Athapascan) group, call the Arctic caribou Ɂekwǫ̀ and the boreal woodland caribou tǫdzı.[47] The Gwichʼin (also a Dene group) have over 24 distinct caribou-related words.[48]
Reindeer are also called tuttu by the Greenlandic Inuit[49] and hreindýr, sometimes rein, by the Icelanders.
Evolution
The "glacial-interglacial cycles of the upper Pleistocene had a major influence on the evolution" of Rangifer species and other Arctic and sub-Arctic species. Isolation of tundra-adapted species Rangifer in Last Glacial Maximum refugia during the last glacial – the Wisconsin glaciation in North America and the Weichselian glaciation in Eurasia – shaped "intraspecific genetic variability" particularly between the North American and Eurasian parts of the Arctic.[5]
Reindeer/caribou (Rangifer) are in the subfamily Odocoileinae, along with roe deer (Capreolus), Eurasian elk/moose (Alces), and water deer (Hydropotes). These antlered cervids split from the horned ruminants Bos (cattle and yaks), Ovis (sheep) and Capra (goats) about 36 million years ago.[50] The Eurasian clade of Odocoileinae (Capreolini, Hydropotini and Alcini) split from the New World tribes of Capreolinae (Odocoileini and Rangiferini) in the Late Miocene, 8.7–9.6 million years ago.[51] Rangifer “evolved as a mountain deer, ...exploiting the subalpine and alpine meadows...”.[14] Rangifer originated in the Late Pliocene and diversified in the Early Pleistocene, a 2+ million-year period of multiple glacier advances and retreats. Several named Rangifer fossils in Eurasia and North America predate the evolution of modern tundra reindeer.
Archaeologists distinguish “modern” tundra reindeer and barren-ground caribou from primitive forms — living and extinct — that did not have adaptations to extreme cold and to long distance migration. They include a broad, high muzzle to increase the volume of the nasal cavity to warm and moisten the air before it enters the throat and lungs, bez tines set close to the brow tines, distinctive coat patterns, short legs and other adaptations for running long distances, and multiple behaviors suited to tundra, but not to forest (such as synchronized calving and aggregation during rutting and post-calving).[52] As well, many genes, including those for vitamin D metabolism, fat metabolism, retinal development, circadian rhythm, and tolerance to cold temperatures, are found in tundra caribou that are lacking or rudimentary in forest types.[53][54] For this reason, forest-adapted reindeer and caribou could not survive in tundra or polar deserts. The oldest undoubted Rangifer fossil is from Omsk, Russia, dated to 2.1-1.8 Ma.[55] The oldest North American Rangifer fossil is from the Yukon, 1.6 million years before present (BP).[56] A fossil skull fragment from Süßenborn, Germany, R. arcticus stadelmanni,[57] (which is probably misnamed) with “rather thin and cylinder-shaped” antlers, dates to the Middle Pleistocene (Günz) Period, 680,000-620,000 BP.[58] Rangifer fossils become increasingly frequent in circumpolar deposits beginning with the Riss glaciations, the second youngest of the Pleistocene Epoch, roughly 300,000–130,000 BP. By the 4-Würm period (110,000–70,000 to 12,000–10,000 BP), its European range was extensive, supplying a major food source for prehistoric Europeans.[59] North American fossils outside of Beringia that predate the Last Glacial Maximum (LGM) are of Rancholabrean age (240,000–11,000 years BP) and occur along the fringes of the Rocky Mountain and Laurentide ice sheets as far south as northern Alabama; and in Sangamonian deposits (~100,000 years BP) from western Canada.[60]
A R. t. pearyi-sized caribou occupied Greenland before and after the LGM and persisted in a relict enclave in northeastern Greenland until it went extinct about 1900 (see discussion of R. t. eogroenlandicus below). Archaeological excavations showed that larger barren-ground-sized caribou appeared in western Greenland about 4,000 years ago.[61]
The late Valerius Geist (1998)[14] dates the Eurasian reindeer radiation dates to the large Riss glaciation (347,000 to 128,000 years ago), based on the Norwegian-Svalbard split 225,000 years ago.[62] Finnish forest reindeer (R. t. fennicus) likely evolved from Cervus [Rangifer] geuttardi Desmarest, 1822, a reindeer that adapted to forest habitats in Eastern Europe as forests expanded during an interglacial period before the LGM (the Würmian or Weichsel glaciation);.[58] The fossil species geuttardi was later replaced by R. constantini, which was adapted for grasslands,[63] in a second immigration 19,000–20,000 years ago when the LGM turned its forest habitats into tundra, while fennicus survived in isolation in southwestern Europe.[58] R. constantini was then replaced by modern tundra/barren-ground caribou adapted to extreme cold, probably in Beringia, before dispersing west (R. t. tarandus in the Scandinavian mountains and R. t. sibiricus across Siberia) and east (R. t. arcticus in the North American Barrenlands) when rising seas isolated them. Likewise in North America, DNA analysis shows that woodland caribou (R. caribou) diverged from primitive ancestors of tundra/barren-ground caribou not during the LGM, 26,000–19,000 years ago, as previously assumed, but in the Middle Pleistocene around 357,000 years ago.[64][65] At that time, modern tundra caribou had not even evolved. Woodland caribou are likely more related to extinct North American forest caribou than to barren-ground caribou. For example, the extinct caribou Torontoceros [Rangifer] hypogaeus, had features (robust and short pedicles, smooth antler surface, and high position of second tine) that relate it to forest caribou.[66]
Humans started hunting reindeer in both the Mesolithic and Neolithic Periods, and humans are today the main predator in many areas. Norway and Greenland have unbroken traditions of hunting wild reindeer from the Last Glacial Period until the present day. In the non-forested mountains of central Norway, such as Jotunheimen, it is still possible to find remains of stone-built trapping pits, guiding fences and bow rests, built especially for hunting reindeer. These can, with some certainty, be dated to the Migration Period, although it is not unlikely that they have been in use since the Stone Age.
Cave paintings by ancient Europeans include both tundra and forest types of reindeer.[14]
A 2022 study of ancient environmental DNA from the Early Pleistocene (2 million years ago) Kap Kobenhavn Formation of northern Greenland identified preserved DNA fragments of Rangifer, identified as basal but potentially ancestral to modern reindeer. This suggests that reindeer have inhabited Greenland since at least the Early Pleistocene. Around this time, northern Greenland was 11–19 °C warmer than the Holocene, with a boreal forest hosting a species assemblage with no modern analogue. These are among the oldest DNA fragments ever sequenced.[67][68]
Conservation
Current status
While overall widespread and numerous, some reindeer species and subspecies are rare and three subspecies have already become extinct.[29][30] As of 2015, the IUCN has classified the reindeer as Vulnerable due to an observed population decline of 40% over the last +25 years.[2] According to IUCN, Rangifer tarandus as a species is not endangered because of its overall large population and its widespread range.[2]
In North America, the Queen Charlotte Islands caribou[204][30][29] and the East Greenland caribou both became extinct in the early 20th century, the Peary caribou is designated as Endangered, the boreal woodland caribou is designated as Threatened and some individual populations are endangered as well. While the barren-ground caribou is not designated as Threatened, many individual herds — including some of the largest — are declining and there is much concern at the local level.[205] Grant's caribou, a small, pale subspecies endemic to the western end of the Alaska Peninsula and the adjacent islands,[90] has not been assessed as to its conservation status.
The status of the Dolphin-Union "herd" was upgraded to Endangered in 2017.[206] In NWT, Dolphin-Union caribou were listed as Special Concern under the NWT Species at Risk (NWT) Act (2013).
Both the Selkirk Mountains caribou (Southern Mountain population DU9) and the Rocky Mountain caribou (Central Mountain population DU8) are classified as Endangered in Canada in regions such as southeastern British Columbia at the Canada–United States border, along the Columbia and Kootenay Rivers and around Kootenay Lake. Rocky Mountain caribou are extirpated from Banff National Park,[207] but a small population remains in Jasper National Park and in mountain ranges to the northwest into British Columbia. Montane caribou are now considered extirpated in the contiguous United States, including Washington and Idaho. Osborn's caribou (Northern Mountain population DU7) is classified as Threatened in Canada.
In Eurasia, the Sakhalin reindeer is extinct (and has been replaced by domestic reindeer) and reindeer on most of the Novaya Zemlya islands have also been replaced by domestic reindeer, although some wild reindeer still persist on the northern islands.[24] Many Siberian tundra reindeer herds have declined, some dangerously, but the Taymir herd remains strong and in total about 940,000 wild Siberian tundra reindeer were estimated in 2010.[17]
There is strong regional variation in Rangifer herd size. By 2013, many caribou herds in North America had "unusually low numbers" and their winter ranges in particular were smaller than they used to be.[205] Caribou numbers have fluctuated historically, but many herds are in decline across their range.[179] There are many factors contributing to the decline in numbers.[180]
Boreal woodland caribou
Ongoing human development of their habitat has caused populations of boreal woodland caribou to disappear from their original southern range. In particular, boreal woodland caribou were extirpated in many areas of eastern North America in the beginning of the 20th century. Professor Marco Musiani of the University of Calgary said in a statement that "The woodland caribou is already an endangered subspecies in southern Canada and the United States...[The] warming of the planet means the disappearance of their critical habitat in these regions. Caribou need undisturbed lichen-rich environments and these types of habitats are disappearing."[208]
Boreal woodland caribou were designated as Threatened in 2002 by the Committee on the Status of Endangered Wildlife in Canada, (COSEWIC).[35] Environment Canada reported in 2011 that there were approximately 34 000 boreal woodland caribou in 51 ranges remaining in Canada (Environment Canada, 2011b).[36] "According to Geist, the "woodland caribou is highly endangered throughout its distribution right into Ontario."[7]
In 2002, the Atlantic-Gaspésie population DU11 of the boreal woodland caribou was designated as Endangered by COSEWIC. The small isolated population of 200 animals was at risk from predation and habitat loss.
Peary caribou
In 1991, COSEWIC assigned "endangered status" to the Banks Island and High Arctic populations of the Peary caribou. The Low Arctic population of the Peary caribou was designated as Threatened. In 2004, all three were designated as "endangered."[204] In 2015, COSEWIC returned the status to Threatened.
Milking
Crossing frozen water
Drawing a wagon
Drawing a one-man sled
Reindeer-mounted cavalry
