Arctic Ground Squirrel
   HOME

TheInfoList



OR:

The Arctic ground squirrel (''Urocitellus parryii'') (
Inuktitut Inuktitut ( ; , Inuktitut syllabics, syllabics ), also known as Eastern Canadian Inuktitut, is one of the principal Inuit languages of Canada. It is spoken in all areas north of the North American tree line, including parts of the provinces of ...
: ''ᓯᒃᓯᒃ, siksik'') is a
species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of
ground squirrel Ground squirrels are rodents of the squirrel family (Sciuridae) that generally live on the ground or in burrows, rather than in trees like the tree squirrels. The term is most often used for the medium-sized ground squirrels, as the larger ones ar ...
in the squirrel family
Sciuridae Squirrels are members of the family Sciuridae (), a family that includes small or medium-sized rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrel ...
that is native to the
Arctic The Arctic (; . ) is the polar regions of Earth, polar region of Earth that surrounds the North Pole, lying within the Arctic Circle. The Arctic region, from the IERS Reference Meridian travelling east, consists of parts of northern Norway ( ...
and
Subarctic The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of hemiboreal regions and covering much of Alaska, Canada, Iceland, the north of Fennoscandia, Northwestern Russia, Siberia, and the Cair ...
regions of the
Northern Hemisphere The Northern Hemisphere is the half of Earth that is north of the equator. For other planets in the Solar System, north is defined by humans as being in the same celestial sphere, celestial hemisphere relative to the invariable plane of the Solar ...
, mainly in
North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...
and
Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...
. For some people in
Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...
, particularly around the
Aleutian Islands The Aleutian Islands ( ; ; , "land of the Aleuts"; possibly from the Chukchi language, Chukchi ''aliat'', or "island")—also called the Aleut Islands, Aleutic Islands, or, before Alaska Purchase, 1867, the Catherine Archipelago—are a chain ...
, the
rodents Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are n ...
are known as "parka" squirrels, likely due to their pelts being used for the ruff on parkas and other cold-weather clothing.


Taxonomy

Subspecies listed alphabetically. *''U. p. ablusus'' Osgood, 1903 *''U. p. kennicottii'' Ross, 1861Barrow ground squirrel ( Northern Alaska, N.
Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...
and N.
Northwest Territories The Northwest Territories is a federal Provinces and territories of Canada, territory of Canada. At a land area of approximately and a 2021 census population of 41,070, it is the second-largest and the most populous of Provinces and territorie ...
) *''U. p. kodiacensis'' Ross, 1861
Kodiak Island Kodiak Island (, ) is a large island on the south coast of the U.S. state of Alaska, separated from the Alaska mainland by the Shelikof Strait. The largest island in the Kodiak Archipelago, Kodiak Island is the second largest island in the Un ...
ground squirrel *''U. p. leucostictus'' Brandt, 1844 *''U. p. lyratus'' Hall and Gilmore, 1932 – St. Lawrence Island ground squirrel *''U. p. nebulicola'' Osgood, 1903Shumagin Islands ground squirrel ( Aleutians East Borough; islands of Koniuji, Korovin, Nagai, Popof, Simeonof, Unga) *''U. p. osgoodi'' Merriam, 1900 – Osgood's Arctic ground squirrel (south of the
Brooks Range The Brooks Range (Gwich’in language, Gwich'in: ''Gwazhał'') is a mountain range in far northern North America stretching some from west to east across northern Alaska into Canada's Yukon Territory. Reaching a peak elevation of on Mount Isto, ...
in Alaska, near Fort Yukon and
Circle A circle is a shape consisting of all point (geometry), points in a plane (mathematics), plane that are at a given distance from a given point, the Centre (geometry), centre. The distance between any point of the circle and the centre is cal ...
) *''U. p. parryii'' Richardson, 1825 *''U. p. plesius'' Osgood, 1900 *''U. p. stejnegeri'' J. A. Allen, 1903


Description

The Arctic ground squirrel typically has a beige-tan pelage with a lightly-spotted backside. Similar to the related
prairie dog Prairie dogs (genus ''Cynomys'') are herbivorous burrowing Marmotini, ground squirrels native to the grasslands of North America. There are five recognized species of prairie dog: black-tailed prairie dog, black-tailed, white-tailed prairie dog ...
, it has a shorter face than the typical
arboreal Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally (scansorial), but others are exclusively arboreal. The hab ...
squirrels–due to its lifestyle of burrowing–as well as smaller ears, with a dark tail and white markings around the eyes. During the brief boreal summer, Arctic ground squirrels undergo an annual molting (coat shedding/re-growth) cycle in preparation for the onset of colder weather; this is seen in other Arctic species, as well, such as the white winter coat of the
Arctic fox The Arctic fox (''Vulpes lagopus''), also known as the white fox, polar fox, or snow fox, is a small species of fox native to the Arctic regions of the Northern Hemisphere and common throughout the Tundra#Arctic tundra, Arctic tundra biome. I ...
,
Arctic The Arctic (; . ) is the polar regions of Earth, polar region of Earth that surrounds the North Pole, lying within the Arctic Circle. The Arctic region, from the IERS Reference Meridian travelling east, consists of parts of northern Norway ( ...
and snowshoe hares, ermine (stoat), and even some birds, such as the
rock ptarmigan The rock ptarmigan (''Lagopus muta'') is a medium-sized game bird in the grouse family. It is known simply as the ptarmigan in Europe. It is the official bird for the Canadian territory of Nunavut, where it is known as the ''aqiggiq'' (ᐊᕿ ...
. Summer coats include reddish and yellow colorations along the cheeks and sides of the body; in the fall, these red patches are shed and replaced by a more silvery color. The lighter coloration in winter helps the ground squirrels to camouflage against the often snow-white ground and better evade predators, such as snowy owls or foxes. The average length of an Arctic ground squirrel is approximately . Since Arctic ground squirrels undergo drastic seasonal changes in body mass, it is difficult to give an average mass; adult females are close to , while males may weigh nearly heavier.


Distribution and habitat

The Arctic ground squirrel can be found in parts of western
Northern Canada Northern Canada (), colloquially the North or the Territories, is the vast northernmost region of Canada, variously defined by geography and politics. Politically, the term refers to the three Provinces_and_territories_of_Canada#Territories, terr ...
, from the
Arctic Circle The Arctic Circle is one of the two polar circles, and the northernmost of the five major circle of latitude, circles of latitude as shown on maps of Earth at about 66° 34' N. Its southern counterpart is the Antarctic Circle. The Arctic Circl ...
to the
Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...
, northern
British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...
and the
Northwest Territories The Northwest Territories is a federal Provinces and territories of Canada, territory of Canada. At a land area of approximately and a 2021 census population of 41,070, it is the second-largest and the most populous of Provinces and territorie ...
; west into
Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...
, the
Aleutian Islands The Aleutian Islands ( ; ; , "land of the Aleuts"; possibly from the Chukchi language, Chukchi ''aliat'', or "island")—also called the Aleut Islands, Aleutic Islands, or, before Alaska Purchase, 1867, the Catherine Archipelago—are a chain ...
archipelago, and across to the
Russian Far East The Russian Far East ( rus, Дальний Восток России, p=ˈdalʲnʲɪj vɐˈstok rɐˈsʲiɪ) is a region in North Asia. It is the easternmost part of Russia and the Asia, Asian continent, and is coextensive with the Far Easte ...
(
Siberia Siberia ( ; , ) is an extensive geographical region comprising all of North Asia, from the Ural Mountains in the west to the Pacific Ocean in the east. It has formed a part of the sovereign territory of Russia and its predecessor states ...
), including the
Kamchatka Peninsula The Kamchatka Peninsula (, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and western coastlines, respectively. Immediately offshore along the Pacific ...
. The St. Lawrence Island subspecies (''U. p. lyratus'') of Arctic ground squirrel is found on its namesake island in the
Bering Sea The Bering Sea ( , ; rus, Бе́рингово мо́ре, r=Béringovo móre, p=ˈbʲerʲɪnɡəvə ˈmorʲe) is a marginal sea of the Northern Pacific Ocean. It forms, along with the Bering Strait, the divide between the two largest landmasse ...
; the Kodiak Island subspecies (''U. p. kodiacensis'') is found on the
Alaska Peninsula The Alaska Peninsula (also called Aleut Peninsula or Aleutian Peninsula, ; Sugpiaq language, Sugpiaq: ''Aluuwiq'', ''Al'uwiq'') is a peninsula extending about to the southwest from the mainland of Alaska and ending in the Aleutian Islands. T ...
, namely Kodiak. The Arctic ground squirrel has evolved with and is found on the North American Arctic
tundra In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic ...
; depending on the subspecies, its preferred habitats are typically hillside or mountain slopes,
riparian A riparian zone or riparian area is the interface between land and a river or stream. In some regions, the terms riparian woodland, riparian forest, riparian buffer zone, riparian corridor, and riparian strip are used to characterize a ripar ...
areas (such as river flats, banks or lake shores) or tundra ridges. Arctic ground squirrels prefer to live in sandy soil due to its ease of manipulation for burrowing, and its superior drainage as opposed to richer soils. Arctic ground squirrels make shallow tunnels and burrows in locations where the
permafrost Permafrost () is soil or underwater sediment which continuously remains below for two years or more; the oldest permafrost has been continuously frozen for around 700,000 years. Whilst the shallowest permafrost has a vertical extent of below ...
will not prevent them from digging. The more southerly subspecies typically inhabit open meadows and open tundra habitats.Animal Diversity Web
/ref>


Fossil record

The Arctic ground squirrel has an extensive
fossil record A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
from the
Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...
. During the
Last Glacial Maximum The Last Glacial Maximum (LGM), also referred to as the Last Glacial Coldest Period, was the most recent time during the Last Glacial Period where ice sheets were at their greatest extent between 26,000 and 20,000 years ago. Ice sheets covered m ...
, it was abundant in areas such as the Klondike region where it is currently rare or absent. Fossilised Arctic ground squirrel nests and caches have also been used for palaeoenvironmental reconstruction; ''Calamagrostis canadensis'', ''Carex albonigra,'' and ''Koeleria'' sp. are common in caches from Late Pleistocene Alaska, indicating the presence of an aerially extensive mammoth steppe ecosystem in the region at this time.


Behaviour

The diurnal Arctic ground squirrel lives on the tundra, where it may fall prey to the Arctic and the
red fox The red fox (''Vulpes vulpes'') is the largest of the true foxes and one of the most widely distributed members of the order Carnivora, being present across the entire Northern Hemisphere including most of North America, Europe and Asia, plus ...
,
wolverine The wolverine ( , ; ''Gulo gulo''), also called the carcajou or quickhatch (from East Cree, ''kwiihkwahaacheew''), is the largest land-dwelling species, member of the family Mustelidae. It is a muscular carnivore and a solitary animal. The w ...
,
Canada Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
and
Eurasian lynx The Eurasian lynx (''Lynx lynx'') is one of the four wikt:extant, extant species within the medium-sized wild Felidae, cat genus ''Lynx''. It is widely distributed from Northern Europe, Northern, Central Europe, Central and Eastern Europe to Cent ...
,
brown bear The brown bear (''Ursus arctos'') is a large bear native to Eurasia and North America. Of the land carnivorans, it is rivaled in size only by its closest relative, the polar bear, which is much less variable in size and slightly bigger on av ...
, snowy owls and
eagle Eagle is the common name for the golden eagle, bald eagle, and other birds of prey in the family of the Accipitridae. Eagles belong to several groups of Genus, genera, some of which are closely related. True eagles comprise the genus ''Aquila ( ...
s. It is one of the few Arctic mammal species which hibernates in the winter, similarly to the
little brown bat The little brown bat or little brown myotis (''Myotis lucifugus'') is an endangered species of mouse-eared bat, mouse-eared microbat found in North America. It has a small body size and glossy brown fur. It is similar in appearance to several ...
and the closely-related
marmot Marmots are large ground squirrels in the genus ''Marmota'', with 15 species living in Asia, Europe, and North America. These herbivores are active during the summer, when they can often be found in groups, but are not seen during the winter, w ...
. In the summer, it forages for
tundra In physical geography, a tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. There are three regions and associated types of tundra: #Arctic, Arctic, Alpine tundra, Alpine, and #Antarctic ...
plant Plants are the eukaryotes that form the Kingdom (biology), kingdom Plantae; they are predominantly Photosynthesis, photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with c ...
s,
seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...
s, and
fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...
to increase
body fat Adipose tissue (also known as body fat or simply fat) is a loose connective tissue composed mostly of adipocytes. It also contains the stromal vascular fraction (SVF) of cells including preadipocytes, fibroblasts, Blood vessel, vascular endothel ...
for its winter hibernation. By late summer, the male Arctic ground squirrel begins to store food in its cache so that, come springtime, it will have a food source until the any new vegetation has grown. Their burrows are lined with
lichen A lichen ( , ) is a hybrid colony (biology), colony of algae or cyanobacteria living symbiotically among hypha, filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualism (biology), m ...
s,
leaves A leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, ...
, grasses, and muskox hair, amongst other animal fibers they may find. Communication between squirrels is done through both vocal and physical means. When they meet, nose to nose contact is made or other body parts are pressed together. The "tsik-tsik" calls are made in response to threats and vary as between different predators. Deep guttural sounds are used to indicate land-based predators while short "band whistle" chatter indicates danger from the air.


Hibernation

The Arctic ground squirrel hibernates over winter from early August to late April in adult females and from late September to early April for adult males, at which time it can reduce its body temperatures from to as little as . During hibernation, its core body temperature reaches temperatures down to and its heart rate drops to about one beat per minute.
Peripheral A peripheral device, or simply peripheral, is an auxiliary hardware device that a computer uses to transfer information externally. A peripheral is a hardware component that is accessible to and controlled by a computer but is not a core compo ...
, colonic, and blood temperatures become subzero. The best theory as to why the squirrel's blood doesn't freeze is that the animal is able to cleanse their bodies of ice nucleators which are necessary for the development of ice crystals. In the absence of ice nucleators, body fluids can remain liquid while in supercooled state. This process is being studied with the hope that mechanism present in arctic ground squirrels may provide a path for better preservation of human organs for transplant. The connections between brain cells also wither away in this state. The damage should have resulted in death, but research on related species show that these connections regrow after waking up. In the warmer months, the squirrel is active during the day.


Diet

This squirrel feeds on grasses,
sedges The Cyperaceae () are a family of graminoid (grass-like), monocotyledonous flowering plants known as sedges. The family is large; botanists have described some 5,500 known species in about 90 generathe largest being the "true sedges" (genu ...
, mushrooms, bog rushes, bilberries,
willow Willows, also called sallows and osiers, of the genus ''Salix'', comprise around 350 species (plus numerous hybrids) of typically deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions. Most species are known ...
s, roots, stalks, leaves, leaf buds, flowers,
catkins A catkin or ament is a slim, cylindrical flower cluster (a spike), with inconspicuous or no petals, usually wind-pollinated (anemophilous) but sometimes insect-pollinated (as in ''Salix''). It contains many, usually unisexual flowers, arranged cl ...
, and seeds. They will also eat insects and, occasionally, even supplement their diet with
carrion Carrion (), also known as a carcass, is the decaying flesh of dead animals. Overview Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters (or scavengers) include crows, vultures ...
(such as mice,
snowshoe hare The snowshoe hare (''Lepus americanus''), also called the varying hare or snowshoe rabbit, is a species of hare found in North America. It has the name "snowshoe" because of the large size of its hind feet. The animal's feet prevent it from sink ...
s and
caribou The reindeer or caribou (''Rangifer tarandus'') is a species of deer with circumpolar distribution, native to Arctic, subarctic, tundra, boreal, and mountainous regions of Northern Europe, Siberia, and North America. It is the only represe ...
) as well as juvenile Arctic ground squirrels. Sometimes these squirrels carry food back to their den in their cheeks.


Reproduction

During the mating season, males engage in male-male aggressive encounters for mating rights. Arctic ground squirrels live individually in burrow systems. Mating occurs between mid-April and mid-May (depending on
latitude In geography, latitude is a geographic coordinate system, geographic coordinate that specifies the north-south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from −90° at t ...
) after winter hibernation. Mating includes male-male competition for access to females, and litters are typically sired by multiple males.
Gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregn ...
is approximately 25 days, and results in a litter of 5 to 10, hairless pups. After six weeks, the pups are weaned and this is followed by rapid growth to prepare for the upcoming winter.


Conservation

Although Environment Yukon has not estimated their population size, their conservation status is currently said to be "secure" (Environment Yukon 2013). The Arctic ground squirrel is classified as least concern (LC) on the IUCN Red List (Arkive 2013).Arkive, 2013. Arctic Ground Squirrel. nternet ited November 7th 2013 Available from: http://www.arkive.org/arctic-ground-squirrel/spermophilus-parryii/image-G78548.html


References


Further reading

* Hall, E. Raymond (1981). ''The Mammals of North America.'' 2 volumes. Ronald Press. * * Thorington, R. W. Jr. and R. S. Hoffman (2005). Family Sciuridae. pp. 754–818 in ''Mammal Species of the World a Taxonomic and Geographic Reference.'' D.E. Wilson and D.M. Reeder eds. Johns Hopkins University Press, Baltimore.


External links

* * {{Authority control Urocitellus Mammals of the Arctic Arctic land animals Mammals described in 1825 Mammals of Russia Mammals of Siberia Rodents of the United States Rodents of Canada Fauna of the Holarctic realm Taxa named by John Richardson (naturalist)