So-called "Suicidal March to the Sea" about every 3-4 years. Populations "cycle," increasing greatly approximately every 3-4 years. When this happens, lemmings may migrate in large numbers from densely populated areas in the mountains down to birch forests, searching for food. Encountering natural obstacles, including bodies of water, causes panic and a "flight response." This behavior sometimes takes them into the sea, and large numbers may die. So, they may die in this individual quest for food, but they aren't committing suicide for the sake of the rest of the population.
Predators of the lemming include the snowy owl, grouse buzzard, ermine, and arctic fox.
Perception Channels: tactile ; chemical
Many live in areas of little agricultural importance to humans. Not pests. Not endangered. Highly varying population density (see "Other Comments"). Clearing of forests by humans has increased habitat.
IUCN Red List of Threatened Species: least concern
Some harbor vectors of disease, such as plague.
Social behavior studied by many.
Herbivorous, diet consisting largely of berries, leaves, grasses, bark, lichens, roots, green part of plants, bulbs, mosses, pine needles. Forage both day and night. Graze and dig for roots.
Norway, Sweden, Finland, extreme north west Europe.
Biogeographic Regions: palearctic (Native )
Alpine, tundra, steppe, temperate grasslands, scrub, open forest, rocks.
Terrestrial Biomes: tundra ; savanna or grassland ; mountains
Average lifespan
Status: captivity: 2.0 years.
Other Physical Features: endothermic ; bilateral symmetry
Average mass: 70 g.
Average basal metabolic rate: 1.071 W.
Gestation 16- 28 days. Reach sexual maturity early (females: 2-3 weeks old, males: 6-8 weeks old). Very fecund. Breed in summer and winter. Length of breeding season varies. Mated female may fail to conceive or may abort if exposed to a strange male. Litter size may vary from 1-12 or more litters per year. Some females genetically programmed to bear only female offspring.
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 3.8 g.
Average gestation period: 19 days.
Average number of offspring: 7.
Average age at sexual or reproductive maturity (male)
Sex: male: 44 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 24 days.
