What is the Arctic tundra?

The Arctic tundra is the treeless ecosystem covering Canada's far north above the tree line, where temperatures are too cold and growing seasons too short for trees. The Canadian tundra covers about 2.6 million square kilometres, roughly 26 per cent of Canada's land area, including the Arctic Archipelago, the northern mainland coast from the Beaufort Sea east to Hudson Bay, the eastern coast of Hudson Bay, and the northern parts of Quebec and Labrador. The tree line runs roughly from the Mackenzie Delta southeast to northern Manitoba and across northern Quebec to Labrador.

The tundra environment is characterised by mean annual temperatures below freezing, summer temperatures averaging 5 to 12 degrees Celsius, winter temperatures regularly below minus 30 degrees Celsius, low precipitation (200 to 400 millimetres per year, mostly as snow), permafrost beneath the surface, and a growing season of 60 to 100 days. Vegetation includes about 600 species of low-growing plants: lichens, mosses, sedges, grasses, willows (dwarf), birches (dwarf), Arctic poppy, mountain avens (the Northwest Territories' floral emblem), purple saxifrage, Labrador tea, blueberry, and bearberry.

The tundra supports a small number of well-adapted vertebrates. Large mammals include barren-ground caribou (major herds include the Bathurst, Beverly, Qamanirjuaq, Lorillard, and Porcupine caribou herds, with combined populations historically of more than 2 million but declining significantly since 2000), muskoxen, polar bears (in coastal areas), Arctic wolves, Arctic foxes, lemmings, Arctic hares, and ermine. Birds include snowy owls, ptarmigan (Newfoundland and Labrador's provincial bird), snow geese, brant, plovers, and gyrfalcon. Marine mammals in adjacent waters include polar bears, narwhal, beluga, bowhead, ringed seal, bearded seal, and walrus.

The tundra is the homeland of the Inuit (in coastal areas) and the northern Dene, Innu, and Inuit ancestors of the Pre-Dorset, Dorset, and Thule cultures. About 65,000 Inuit live in 53 communities across Inuit Nunangat (the four Inuit regions of Canada). Climate change is rapidly altering the tundra: shrubs (willows and dwarf birches) are expanding into formerly grass-and-sedge areas, the tree line is moving north, sea ice is retreating, permafrost is thawing, and the timing of plant blooming and animal migration is shifting. The Canadian tundra is protected by Auyuittuq, Sirmilik, Quttinirpaaq, Aulavik, Tuktut Nogait, Wapusk, and Ukkusiksalik national parks (totaling about 100,000 square kilometres), and many National Wildlife Areas, Migratory Bird Sanctuaries, and Inuit Owned Lands.