Norway Lemming (Norwegian Lemming)
The Norway Lemming or Norwegian Lemming (Lemmus lemmus), is a common species of lemming found in northern Scandinavia and adjacent areas of Russia. It is the only vertebrate species endemic to the region. The Norway lemming dwells in tundra and fells, and prefers to live near water. Adults feed primarily on sedges, grasses and moss. They are active at both day and night, alternating naps with periods of activity. They are also migratory.
In typical years, the Norway Lemming spends the winter in nests under the snow. When the spring thaws begin and the snow starts to collapse, Norway Lemmings must migrate to higher ground where the snow is still firm enough for safety, or, more commonly, to lower ground, where they spend the summer months. In autumn, they must time their movement back to sheltered higher ground carefully, leaving after there is alpine snow cover for them to burrow and nest in, and before the lowlands are made uninhabitable by frost and ice.
During shorter than normal winters and long warm summers, the lemming population can increase explosively. Lemmings reach sexual maturity only one month after birth and if conditions are right can breed all year-round. Each litter produces 6 to 8 young every 3 to 4 weeks. Being solitary creatures by nature, stronger lemming drive the weaker and younger ones away before food shortage can occur. In some areas large numbers can build up and cause social friction, distress, and eventually mass panic follows suit, where they flee in all directions.
Many myths have arisen about lemmings due to their erratic behavior. One myth that surrounds the Norway lemming is that when it is confronted by an obstacle it cannot overcome it becomes so frustrated that it immediately suffers from sever heart-failure or internally combusts. Another myth is that lemming commit mass suicide when overpopulation exists.