North American Brown Lemming

North American Brown Lemming
North American Brown Lemming, young
Conservation status
Least Concern (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Rodentia
Family:	Muridae
Genus:	Lemmus
Species:	L. trimucronatus
Binomial name
Lemmus trimucronatus (Richardson, 1825)

The North American brown lemming, Lemmus trimucronatus, is a small North American lemming. Originally called the Siberian Brown Lemming Lemmus sibiricus it was later decided that they formed two distinct species.

The lemming is brown in colour, with a reddish-brown back and rump, while the head and shoulder are grey. In the winter the coat becomes longer and greyer. The female averages 12.5 cm (5.7 in) and weighs 58 g (2.4 oz) while the male averages 13 cm (5.9 in) and weighs 68 g (2.7 oz). Like other lemmings they have small ears, short legs and a very short tail. The feet, both the soles and toes are covered with bristles, are adapted for burrowing.

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 feed mainly on grass shoots and will also eat tundra grass, sedge, moss, bark, berries, lichens and roots. Predators include most carnivores and certain birds and there has been some evidence to suggest that caribou may sometimes eat them. In years when the brown lemming is scarce some predators, such as the Arctic fox may be unable to reproduce.

They 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. The brown lemming is not migratory and when overpopulated (and during mating season) they will fight amongst themselves.

References

1. ^ Linzey, A.V. (2008). Lemmus trimucronatus. In: IUCN 2008. IUCN Red List of Threatened Species. Downloaded on 5 June 2009. Database entry includes a brief justification of why this species is of least concern.

• NatureServe
• Terrestrial Mammals of Nunavut by Ingrid Anand-Wheeler. ISBN 1-55325-035-4