# Brown Lemming (*Lemmus lemmus*)

> The brown lemming is a small, stocky rodent of the Arctic and alpine tundra of Scandinavia and Russia. Weighing only 30 to 112 g and measuring about 15 cm, it feeds on grasses, sedges, moss, and bark and stays active all winter beneath the snow. Lemmings are famous for dramatic population booms and crashes, and they live just one to two years. The species is listed as Least Concern.

- **Category:** Mammal
- **Conservation status (IUCN):** Least Concern
- **Range:** Arctic and alpine tundra of Scandinavia, Russia, Alaska, and Canada — brown lemming in Fennoscandia and Siberia.
- **Canonical page:** https://globalanimalguide.org/animals/lemming/
- **Last reviewed:** 2026-07-16

## Scientific classification

- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Mammalia
- **Order:** Rodentia
- **Family:** Cricetidae
- **Genus:** Lemmus

## Facts at a glance

| Attribute | Value |
| --- | --- |
| Scientific name | Lemmus lemmus |
| Diet | Herbivore — grasses, sedges, moss, and bark |
| Habitat | Arctic and alpine tundra of Scandinavia and Russia |
| Lifespan | 1–2 years in the wild (short-lived rodent) |
| Weight | 30–112 g (0.03–0.11 kg); varies with season |
| Top speed | Up to 8 km/h (5 mph); scurries through tundra runways |
| Conservation status | Least Concern (IUCN) |

## Size and appearance

The brown lemming is a small, round-bodied rodent with dense fur, short legs, tiny ears, and a very short tail, all adaptations for conserving heat in the cold. It weighs only 30 to 112 g and measures around 15 cm long, with its weight varying through the seasons. Its thick coat and compact shape reduce heat loss in the harsh tundra climate. Strong claws help it dig burrows and tunnels through soil and snow.

## Life on the tundra

Lemmings live in the treeless Arctic and alpine tundra of Scandinavia and Russia, among the harshest habitats any mammal endures. Rather than hibernating, they stay active all winter, tunnelling through the insulating layer of snow where the temperature is far milder than the air above. There they build nests of grass and continue to feed and even breed in favourable years. This ability to exploit the space beneath the snow is key to surviving the long polar winter.

## Diet and feeding

The brown lemming is a herbivore that eats grasses, sedges, moss, and bark, feeding almost constantly to fuel its fast metabolism. Because tundra plants are low in nutrients, a lemming must consume large amounts of vegetation each day relative to its size. In winter it gnaws on roots, shoots, and bark reached through its snow tunnels. Its intense grazing can strip patches of tundra during years when the population is high.

## Population booms and crashes

Lemmings are best known for their dramatic population cycles, in which numbers explode roughly every three to five years and then collapse just as sharply. Their rapid breeding, with several litters a year, allows the population to multiply quickly when food and conditions are good. When numbers peak, food runs short and many lemmings disperse in large movements to find new ground. This boom-and-bust pattern ripples through the whole tundra ecosystem.

## The myth of mass suicide

Contrary to popular belief, lemmings do not deliberately hurl themselves off cliffs to their deaths. The myth was cemented by a 1958 Disney film in which the animals were pushed off a ledge for the camera. What really happens is that during population peaks, huge numbers migrate in search of food and some drown while trying to cross rivers or lakes. The truth is a story of desperate dispersal, not deliberate self-destruction.

## Predators and conservation

As a small, abundant rodent, the lemming is a crucial food source for tundra predators such as Arctic foxes, snowy owls, skuas, and stoats. The breeding success of many of these predators rises and falls in step with the lemming cycle. The brown lemming itself is listed as Least Concern by the IUCN, being widespread and, in good years, extremely numerous. These short-lived rodents rarely survive beyond one to two years.

## Frequently asked questions

### Do lemmings really commit mass suicide?

No. The idea that lemmings deliberately jump off cliffs is a myth, popularised by a staged 1958 Disney film. In reality, large numbers migrate during population peaks and some accidentally drown while crossing rivers or lakes.

### What do lemmings eat?

Lemmings are herbivores that eat grasses, sedges, moss, and bark. They feed almost constantly to fuel a fast metabolism, and in winter they gnaw roots and shoots reached through their snow tunnels.

### Where do lemmings live?

The brown lemming lives in the Arctic and alpine tundra of Scandinavia and Russia. It stays active all winter, tunnelling beneath the snow where temperatures are milder than the freezing air above.

### Why do lemming populations rise and fall so dramatically?

Lemmings breed very fast, producing several litters a year, so their numbers can explode roughly every three to five years when conditions are good. When food runs short, the population crashes just as sharply.

### How big is a lemming?

The brown lemming is small, measuring about 15 cm long and weighing only 30 to 112 g. Its stocky body, dense fur, and short limbs all help it conserve heat in the cold tundra.

### How long do lemmings live?

Lemmings are short-lived rodents, typically surviving just one to two years in the wild. High predation and the boom-and-bust nature of their populations keep individual lifespans short.

## Sources

- [IUCN Red List — Lemmus lemmus.](https://www.iucnredlist.org/search?query=Lemmus%20lemmus&searchType=species)
- [Animal Diversity Web — Lemmus lemmus. University of Michigan Museum of Zoology.](https://animaldiversity.org/accounts/Lemmus_lemmus/)

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Source: Global Animal Guide (https://globalanimalguide.org/animals/lemming/). Licensed CC BY-NC 4.0 — free for non-commercial reuse with attribution.