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Lemmus trimucronatus

Nearctic Brown Lemming

Order: Rodentia
Family: Cricetidae

Image of Lemmus trimucronatus
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Conservation Status: Least Concern.

Unlike Norwegian Lemmings, Nearctic Brown Lemmings do not migrate en masse when they overpopulate their homes in the treeless regions of the north, but they do tend to wander. These are stout-bodied, herbivorous rodents with extremely short tails. Their fur is tawny brown to cinnamon, and a rusty-colored patch can be seen on older adults.Nearctic Brown Lemmings are most abundant in low-lying, wet habitats with sedges, grasses, and mosses. They cannot eat dried, dead plants; they must have living ones, so what they eat changes with the seasons. During winter months, they feed heavily on mosses, which are not very digestible. Brown Lemmings have to spend many hours in a 24-hour winter day feeding to get enough nourishment. Arctic predators, including snowy owls, least weasels, and Arctic Foxes rely on Nearctic Brown Lemming, and when Nearctic Brown Lemming are in short supply, these predators usually do not breed successfully.

Also known as:
Siberian Lemming, Brown Lemming

Sexual Dimorphism:
Males are larger than females.

Average: 150 mm
Range: 130-180 mm

Average: 80 g
Range: 45-130 g


In Linnaeus, C. (translated and revised by R. Kerr), 1792. The animal kingdom; or, zoological system of the celebrated Sir Charles Linnaeus. Class I. Mammalia and Class II. Birds. Being a translation of that part of the Systema Naturae, as lately published with great improvements by Professor Gmelin, together with numerous additions from more recent zoological writers and illustrated with copperplates, p. 241.  J. Murray, London, 644 pp.


Mammal Species of the World

Distribution of Lemmus trimucronatus

Image of Lemmus trimucronatus
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