Reindeer, known as caribou in North America, are large herbivores adapted to cold northern environments. These animals are a single species, Rangifer tarandus, and are characterized by their sturdy build and unique antlers, which are grown by both males and many females.
Global Distribution of Wild Reindeer
Wild reindeer populations primarily inhabit circumpolar regions. Their range extends across North America, including Alaska and Canada, and Eurasia, encompassing countries like Norway, Finland, Siberia, and Greenland. These animals are found in two main biomes: the treeless arctic tundra and the northern boreal forests. Historically, their distribution was even wider, reaching as far south as the northern contiguous United States and parts of Europe, but wild populations have largely disappeared from these southern areas.
Reindeer Subspecies and Their Habitats
The distinct habitats of various reindeer subspecies highlight their adaptation to specific environments.
North American Subspecies
In North America, Woodland Caribou prefer mature to old-growth coniferous forests and peatlands, finding abundant lichens for winter forage. These caribou are found across Canada, from Yukon to Labrador, and south to Lake Superior in Ontario, generally staying within their forest ranges without extensive migrations. In contrast, Barren-Ground Caribou inhabit the open arctic tundra for calving and summer grazing, migrating to subarctic forests (taiga) for winter. Their range extends from Alaska across northern Canada to western Greenland, with major herds like the Porcupine and Western Arctic.
Eurasian Subspecies
Eurasian Tundra Reindeer are widespread in Russia, often forming large migratory herds in open tundra landscapes. Mountain Reindeer, primarily found in central and southern Norway, inhabit mountainous terrain; the Hardangervidda plateau in southern Norway is home to a notable population. A unique island population, the Svalbard Reindeer, is found exclusively on Norway’s Svalbard archipelago. These are the smallest subspecies, adapted to the harsh arctic desert climate, residing in non-glaciated areas.
Domesticated Reindeer Herding
Reindeer are also found in managed herds, distinguishing these populations from their wild counterparts. Reindeer herding occurs in northern Scandinavia (Norway, Sweden, Finland) and Russia, as well as in parts of Greenland, Alaska, Mongolia, China, Canada, and a small herd in Scotland. This practice has ancient origins and is central to the cultural and economic lives of many indigenous peoples, such as the Sámi in Fennoscandia. Domesticated reindeer are managed within specific herding areas, often spanning vast territories that include both tundra and taiga regions. While these reindeer are semi-domesticated, they still graze freely for much of the year and migrate between seasonal pastures under human guidance.
Seasonal Migrations and Movement Patterns
Reindeer populations undertake extensive annual migrations. Many wild populations, particularly those inhabiting the tundra, move between summer and winter ranges. During spring, reindeer move northward to coastal or mountainous calving grounds in the tundra to give birth and access nutritious vegetation. These migrations can cover hundreds of miles, making them among the longest terrestrial mammal migrations.
As autumn approaches, these herds migrate southward to winter ranges, often within the boreal forests, where snow cover is less deep and lichens, a primary winter food source, are more accessible. Factors influencing these movements include food availability, snow depth, and avoidance of insects and predators. While spring migrations tend to be consistent, the timing of fall migrations can vary based on weather conditions, such as colder temperatures and the first snowfall.