North American Brown Lemming

The North American Brown Lemming, Lemmus trimucronatus, is a species of lemming found in North America. The lemming is found in the tundra areas of northern Canada (Nunavut, Northwest Territories, Yukon) and Alaska. It is also found on the west coast of British Columbia almost as far south as Vancouver Island. They live underground.

The lemming is brown in color, with a reddish-brown back and rump, while the head and shoulder are grey. In the winter the coat becomes longer and grayer. The female averages 5.7 inches and weighs 2.4 ounces, while the male averages 5.9 inches and weighs 2.7 ounces. Like other lemmings they have small ears, short legs and a very short tail. The feet are adapted for burrowing as it toes and soles are covered with bristles.

Lemmings feed mainly on grass shoots, but may also take in tundra grass, sedge, moss, bark, berries, lichens and roots. Predators include most carnivores and preying birds. Evidence also suggests that caribou have consumed lemmings as well. In years when lemming populations are low, some predators, such as the Arctic Fox, are unable to reproduce.

Lemmings live underground, in colonies, and may produce up to three litters each year, including under the snow in winter. With a gestation period of 23 days the female will give birth from four to nine young. These creatures are non-migratory and will fight other lemmings in conditions where overpopulation exists.