Arctic Lemming

The Arctic lemming (Dicrostonyx groenlandicus) belongs to the order Rodentia, family Cricetidae, and is the sole species of its genus adapted to the high Arctic. It inhabits the tundra biome across northern Canada, Alaska, Greenland, and the Siberian coast, where it lives in dense vegetation and under seasonal snow cover. In summer its fur is brownish‑gray, turning pure white in winter to provide camouflage against snow. Its large hind feet are covered with dense fur, acting as snowshoes that enable it to move across deep snow. Arctic lemmings construct complex burrow systems that provide shelter from predators and extreme temperatures. They play a crucial role in tundra ecosystems as primary herbivores and as a key prey item for Arctic foxes, snowy owls, and ermines. The species is classified as Least Concern by the IUCN due to its wide distribution and large, fluctuating populations, although local declines have been recorded in areas experiencing rapid climate change.

Arctic lemmings exhibit dramatic population cycles, with numbers peaking every three to five years before crashing dramatically. During peak phases they form large colonies that can cover several hundred square meters, while in low phases individuals become more solitary. They are primarily crepuscular, foraging at dawn and dusk to avoid peak predator activity. Territories are defended by scent marking using specialized glands on the flanks, and brief chirps or squeaks are used to signal alarm. Seasonal migrations occur when snow depth exceeds the lemmings’ ability to move, prompting mass movements across the tundra that have historically been misinterpreted as “lemming suicides”. Their social structure is fluid, with dominant males gaining access to the best burrows and females during the breeding season.

The Arctic lemming is a strict herbivore, feeding primarily on the vegetative parts of tundra plants. Its diet consists of grasses (e.g., Poa spp.), sedges (Carex spp.), mosses, lichens, and the leaves and stems of dwarf shrubs such as Salix arctica and Betula nana. During the brief Arctic summer, lemmings may also consume seeds and the occasional insect when plant material is scarce. They consume roughly 5–10% of their body weight each day, which translates to 1.5–3 grams of fresh plant material for an average adult. Foraging occurs both above and below ground; lemmings often pull vegetation into their burrows to create a stored cache that sustains them during periods of heavy snowfall. Their incisors grow continuously, allowing them to gnaw through tough, fibrous plant tissues.

Arctic lemmings reach sexual maturity at 3–4 weeks of age. Breeding commences as soon as snow melts, typically from May to July, and may continue into early August if conditions remain favorable. The gestation period lasts about 21 days, after which females give birth to litters of 4–9 pups. Litter size is positively correlated with maternal body condition and food availability. Females can produce up to three litters per season, resulting in rapid population growth during peak phases. Newborns are altricial, blind and hairless, and are nursed for approximately three weeks before weaning. Parental care is limited to nursing; juveniles become independent shortly after weaning and disperse to establish their own burrows.

The IUCN lists the Arctic lemming as Least Concern, reflecting its extensive range and large overall population, estimated in the tens of millions. However, the species faces several emerging threats. Climate change is the most significant, as warming temperatures alter tundra vegetation composition, reduce snow cover depth, and increase the frequency of freeze‑thaw cycles that can damage burrow structures. Predation pressure from Arctic foxes, snowy owls, and ermines intensifies during population lows, sometimes leading to local extirpations. Human activities such as oil and gas exploration, road construction, and increased tourism can fragment habitat and disturb burrow systems. Although current population trends remain stable overall, localized declines have been documented in parts of Greenland and northern Siberia, prompting calls for continued monitoring and habitat protection measures.

• Arctic lemmings change fur color seasonally, turning white in winter for camouflage.
• Their large, fur‑covered hind feet act as natural snowshoes, allowing movement across deep snow.
• Population cycles can cause massive, synchronized migrations across the tundra.
• They are a keystone prey species, supporting predators like Arctic foxes and snowy owls.
• Despite popular myth, lemmings do not intentionally jump off cliffs; mass movements are driven by environmental pressures.