There is no fox better equipped to handle chilly weather than the Arctic fox—a.k.a. the white fox. Canada’s smallest canid may weigh as little as 3 lbs, but it’s hardy enough to withstand temperatures as low as -50°C. It’s literally built for the cold, with a heavy white coat in the winter, a compact body, and a bushy tail that makes up about 30 per cent of its total body length. The Arctic fox uses that tail like a shawl to wrap around itself when sleeping.
In Canada, the Arctic fox’s range stretches from the northern tip of Ellesmere Island to the southern tip of James Bay. A carnivore, it survives mostly on a diet of lemmings. Foxes with whelps to feed will hunt up to 15 times per night—usually between 4 p.m. and mid-morning the next day. In open areas of tundra, adults catch their prey by chasing and pouncing. But an Arctic fox is smart enough to know how to locate an underground lemming nest, and will dig through the snow to get at it.
What do the foxes do when there are no lemmings?
Since an Arctic fox is so dependent on its lemming food source, the species’ numbers fluctuate with the lemming population. And the lemming population is known to “crash” and then peak. In a crash year, foxes will leave their usual hunting territories and wander for hundreds of kilometres, nomad-like, searching for food. This makes them vulnerable to fatigue and extreme cold—no den to hunker down inside—not to mention, starvation. Consequently, when lemming numbers are low, so are Arctic fox numbers.
White foxes are sometimes blue
The Arctic fox only keeps its snowy-white coat for the winter (just like the snowshoe hare). By May, it begins to shed its heavy fur in place of a thinner, two-tone brown outfit. Some Arctic foxes have a blue-toned coat in the winter; they shed that for a blue-grey coat in the summer. “Blue” foxes appear in almost every Arctic fox population. In Canada, they make up about five per cent of the population; in Greenland, meanwhile, about 50 per cent of white foxes are blue foxes. So…the foxes in Greenland are blue? Huh. Ironic.