Found across the Arctic tundra of northern Canada, and ranging around the top of the world from Alaska to Scandinavia and Russia, the Arctic fox is the smallest of the wild dogs that make their home in the far North. Despite its name, it is a close relative of the red fox and the other true foxes, sharing their pointed muzzle and bushy tail. A dense double coat, short rounded ears, a compact body, and thickly furred pads on the soles of its feet all help the little animal hold on to warmth in a place where few mammals could survive. Prized for its winter pelt, the Arctic fox was once heavily trapped across much of the North.

The Arctic fox's most distinctive feature is a coat that changes with the seasons. Through the long winter the fur grows thick and pure white, hiding the fox against the snow; in summer it thins and turns a brown or grey that blends with bare rock and tundra. Few natural fibres trap heat as well. The two sexes are almost impossible to tell apart, though the males run a little larger and heavier than the females. Even the youngest cubs carry a warm coat within weeks of leaving the den.