Northern Collared Lemming
Encyclopedia
The Northern Collared Lemming (Dicrostonyx groenlandicus), sometimes called the Peary Land Collared Lemming in Canada
, is a small North America
n lemming
. At one time, it was considered to be a subspecies of the Arctic Lemming
(Dicrostonyx torquatus). Some sources believe that several other species of collared lemming
s found in North America are actually subspecies of the Northern Collared Lemming.
It has a short chunky body covered with thick grey fur with a thin black stripe along its back and light grey underparts. It has small ears, short legs and a very short tail. It has a pale brown collar across its chest. In winter, its fur turns white (believed to be the only rodent
that does this) and it has large digging claws on its front feet. It is 14 cm long with a 1.5 cm tail and weighs about 40 g.
This animal is found in the tundra
of northern Canada
, Alaska
and Greenland
. It feeds on grass
es, sedge
s and other green vegetation in summer and twigs of willow
, aspen
and birch
es in winter. Predators include owl
s, gull
s, weasels
, the Arctic Fox
and the Polar Bear
.
Female lemmings have 2 or 3 litters of 4 to 8 young in a year. The young are born in a nest in an underground burrow or concealed in vegetation.
It is active year round, day and night. It makes runways through the surface vegetation and also digs underground burrows above the permafrost
. It burrows under the snow in winter. Lemming populations go through a 3 or 4 year cycle of boom and bust. When their population peaks, lemmings disperse from overcrowded areas.
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, is a small North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
n lemming
Lemming
Lemmings are small rodents, usually found in or near the Arctic, in tundra biomes. They are subniveal animals, and together with voles and muskrats, they make up the subfamily Arvicolinae , which forms part of the largest mammal radiation by far, the superfamily Muroidea, which also includes rats,...
. At one time, it was considered to be a subspecies of the Arctic Lemming
Arctic Lemming
The Arctic Lemming is a species of rodent in the family Cricetidae.It is found only in The Arctic Biomes in Russia and Canada.-References:...
(Dicrostonyx torquatus). Some sources believe that several other species of collared lemming
Collared lemming
Dicrostonyx is a genus of rodent in the family Cricetidae. It contains the collared lemmings.It contains the following species:* Northern Collared Lemming * Ungava Collared Lemming...
s found in North America are actually subspecies of the Northern Collared Lemming.
It has a short chunky body covered with thick grey fur with a thin black stripe along its back and light grey underparts. It has small ears, short legs and a very short tail. It has a pale brown collar across its chest. In winter, its fur turns white (believed to be the only rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....
that does this) and it has large digging claws on its front feet. It is 14 cm long with a 1.5 cm tail and weighs about 40 g.
This animal is found in the tundra
Tundra
In physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine...
of northern Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, Alaska
Alaska
Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...
and Greenland
Greenland
Greenland is an autonomous country within the Kingdom of Denmark, located between the Arctic and Atlantic Oceans, east of the Canadian Arctic Archipelago. Though physiographically a part of the continent of North America, Greenland has been politically and culturally associated with Europe for...
. It feeds on grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
es, sedge
Cyperaceae
Cyperaceae are a family of monocotyledonous graminoid flowering plants known as sedges, which superficially resemble grasses or rushes. The family is large, with some 5,500 species described in about 109 genera. These species are widely distributed, with the centers of diversity for the group...
s and other green vegetation in summer and twigs of willow
Willow
Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...
, aspen
Aspen
Populus section Populus, of the Populus genus, includes the aspen trees and the white poplar Populus alba. The five typical aspens are all native to cold regions with cool summers, in the north of the Northern Hemisphere, extending south at high altitudes in the mountains. The White Poplar, by...
and birch
Birch
Birch is a tree or shrub of the genus Betula , in the family Betulaceae, closely related to the beech/oak family, Fagaceae. The Betula genus contains 30–60 known taxa...
es in winter. Predators include owl
Owl
Owls are a group of birds that belong to the order Strigiformes, constituting 200 bird of prey species. Most are solitary and nocturnal, with some exceptions . Owls hunt mostly small mammals, insects, and other birds, although a few species specialize in hunting fish...
s, gull
Gull
Gulls are birds in the family Laridae. They are most closely related to the terns and only distantly related to auks, skimmers, and more distantly to the waders...
s, weasels
Mustelidae
Mustelidae , commonly referred to as the weasel family, are a family of carnivorous mammals. Mustelids are diverse and the largest family in the order Carnivora, at least partly because in the past it has been a catch-all category for many early or poorly differentiated taxa...
, the Arctic Fox
Arctic fox
The arctic fox , also known as the white fox, polar fox or snow fox, is a small fox native to Arctic regions of the Northern Hemisphere and is common throughout the Arctic tundra biome. The Greek word alopex, means a fox and Vulpes is the Latin version...
and the Polar Bear
Polar Bear
The polar bear is a bear native largely within the Arctic Circle encompassing the Arctic Ocean, its surrounding seas and surrounding land masses. It is the world's largest land carnivore and also the largest bear, together with the omnivorous Kodiak Bear, which is approximately the same size...
.
Female lemmings have 2 or 3 litters of 4 to 8 young in a year. The young are born in a nest in an underground burrow or concealed in vegetation.
It is active year round, day and night. It makes runways through the surface vegetation and also digs underground burrows above the permafrost
Permafrost
In geology, permafrost, cryotic soil or permafrost soil is soil at or below the freezing point of water for two or more years. Ice is not always present, as may be in the case of nonporous bedrock, but it frequently occurs and it may be in amounts exceeding the potential hydraulic saturation of...
. It burrows under the snow in winter. Lemming populations go through a 3 or 4 year cycle of boom and bust. When their population peaks, lemmings disperse from overcrowded areas.