Wintering Grounds - Caribou Activities

November to February

During winter, caribou switch to a diet primarily of lichens. Their favorite lichens grow on the ground in the boreal forest, sometimes in dense mats. Occasionally, lichens are also found on alpine tundra slopes. Caribou can smell lichens even under deep snow. Often, all the snow in a valley becomes cratered by caribou digging for lichens. Lichens are generally less abundant on the arctic tundra, which explains in part why Porcupine Herd caribou migrate south for the winter. Lichens are very rich in carbohydrates, which the caribou need for energy. However, lichens are very poor in protein, which animals need for growth. Consequently, caribou tend to loose weight all winter.

Caribou hair is excellent insulation. Caribou also have other adaptations that help them cope with the bitter temperatures of arctic winters. They use their specially adapted, shovel-shaped hooves to paw away snow to get at lichens. Still, winter is a hard time. Deep or crusty snow can make it difficult for caribou to move and feed, while the same conditions make it easier for wolves to run across the surface of the snow to hunt and kill caribou. Old, sick, or weak caribou often don't survive to spring.