Arctic ground squirrel
| Arctic ground squirrel | |
|---|---|
.jpg) |
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| Conservation status | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Subphylum: | Vertebrata |
| Class: | Mammalia |
| Order: | Rodentia |
| Family: | Sciuridae |
| Genus: | Spermophilus |
| Species: | S. parryii |
| Binomial name | |
| Spermophilus parryii Richardson, 1825 |
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| Subspecies | |
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10 ssp., see text |
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| Synonyms | |
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Urocitellus parryii |
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The Arctic ground squirrel (Urocitellus parryii) is a species of ground squirrel native to the Arctic. People in Alaska, particularly around the Aleutians, refer to them as "Parka" (pronounced "par'kee") squirrels. probably because their pelt is good for making the fur edging on the hoods of Parka style jackets. [2]
Contents |
Subspecies [edit]
Listed alphabetically.[3]
- S. p. ablusus Osgood, 1903
- S. p. kennicottii Ross, 1861 – Barrow ground squirrel (northern Alaska, northern Yukon, and northern Northwest Territories)
- S. p. kodiacensis Ross, 1861
- S. p. leucostictus Brandt, 1844
- S. p. lyratus Hall and Gilmore, 1932
- S. p. nebulicola Osgood, 1903
- S. p. osgoodi Merriam, 1900
- S. p. parryii Richardson, 1825
- S. p. plesius Osgood, 1900
- S. p. stejnegeri J. A. Allen, 1903
Background [edit]
The diurnal Arctic ground squirrel lives on the tundra and is prey to the Arctic Fox, the Red Fox, wolverine, lynx, the Grizzly Bear, and eagles. It is one of the few Arctic animals, along with their close relatives the marmots[4] and the un-related little brown bat that hibernate.[5] In the summer it forages for tundra plants, seeds, and fruit to increase body fat for its winter hibernation. By late summer the male arctic ground squirrel begins to store food in its burrow so that in the spring[6] it will have edible food until the new vegetation has grown. The burrows are lined with lichens, leaves, and muskox hair.
During hibernation, its brain drops to just above freezing, its core body temperature reaches temperatures down to -2.9°C[7] and its heart rate drops to ~1BPM. Peripheral, colonic, and blood temperatures become subzero by means of supercooling.
Geographic range [edit]
The Arctic ground squirrel can be found in regions of Northern Canada ranging from the Arctic Circle to northern British Columbia, and down to the southern border of the Northwest Territories, as well as Alaska and Siberia.[1]
Habitat [edit]
The Arctic ground squirrel inhabits dry Arctic tundra and open meadows in the most southern habitats of this species.[8]
Physical description [edit]
The Arctic ground squirrel has a beige and tan coat with a white-spotted back. This squirrel has a short face, small ears, a dark tail and white markings around its eyes. Arctic ground squirrels undergo a coat change from summer to winter. Summer coats include red/yellow colorations along the cheeks and sides of the animal. In fall, these red patches are replaced with silvery fur. The average length of an Arctic ground squirrel is approximately 39 cm (15 in). Since arctic ground squirrels undergo drastic seasonal changes in body mass, it is difficult[9] to give an average mass, but for adult females it is close to 750 g (26 oz), however, males generally are around 100 g (3.5 oz) heavier than females.[8]
Reproduction [edit]
Arctic ground squirrels live individually in burrow systems. Mating occurs between mid-April and mid-May (depending on latitude) after winter hibernation. Mating includes male-male competition for access to females, and litters are typically sired by multiple males. Gestation is approximately 25 days, and results in a litter of 5 to 10, 10 g (0.35 oz) hairless pups. After 6 weeks the pups are weaned and this is followed by rapid growth to prepare for the upcoming winter.[8]
Behaviour [edit]
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,[10] at which time it can reduce its body temperatures from 37 °C (99 °F) to as little as −3 °C (27 °F).[11] In the warmer months, the squirrel is active during the day time.
During the mating season, males engage in male-male aggressive encounters for the mating rights.[12]
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.[8]
Food habits [edit]
This squirrel feeds on grasses, sedges, mushrooms, bog rushes, bilberries, willows, roots, stalks, leaves, flowers, and seeds. Sometimes this squirrel carries food back to its den in its cheeks.[8]
References [edit]
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Wikimedia Commons has media related to: Arctic ground squirrel |
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Wikispecies has information related to: Arctic ground squirrel |
- ^ a b Linzey, A. V. (2008). Urocitellus parryii. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 8 January 2009.
- ^ http://togiak.fws.gov/wildlife/squirrels.htm
- ^ Spermophilus parryii, MSW3
- ^ Alaska Marmot
- ^ The Long Sleep: Which Animals Hibernate?
- ^ Arctic Ground Squirrel, Environment Yukon
- ^ Liu Y, Hu W, Wang H, Lu M, Shao C, Menzel C, Yan Z, Ying L, Zhao S, Khaitovich P, Liu M, Chen W, Barnes BM, and Yan J: Genomic analysis of miRNAs in an extreme mammalian hibernator, the Arctic Ground Squirrel. Physiological Genomics 42A:39-51. (2010)
- ^ a b c d e Animal Diversity Web
- ^ Buck, C.L.; Barnes, B.M. (1999). "Annual cycle of body composition and hibernation in free-living arctic ground squirrels". Journal of Mammology 80 (2): 430–442.
- ^ Buck, C.L.; Breton, A., Kohl, F., Toien, O., Barnes, B.M. (2008). "Overwinter body temperature patterns in free-living Arctic Ground Squirrels (Spermophilus parryii)". Hypometabolism in Animals: Hibernation, Torpor and Cryobiology: 317–326.
- ^ Barnes, Brian M. (1989-06-30). "Freeze Avoidance in a Mammal: Body Temperatures Below 0°C in an Arctic Hibernator". Science (American Association for the Advancement of Science) 244: 1593–1595. doi:10.1126/science.2740905. PMID 2740905. Retrieved 2009-08-12.
- ^ Buck, C.L.; Barnes, B.M. (2003). "Androgen in free-living arctic ground squirrels: seasonal changes and influence of staged male-male aggressive encounters". Hormones and Behavior (43): 318–326.
Further reading [edit]
- Barnes, Brian M. (1989-06-30). "Freeze Avoidance in a Mammal: Body Temperatures Below 0°C in an Arctic Hibernator". Science (American Association for the Advancement of Science) 244: 1593–1595. doi:10.1126/science.2740905. PMID 2740905. Retrieved 2009-08-12.
- Hall, E. Raymond. 1981. The Mammals of North America. 2 volumes. Ronald Press.
- Helgen, K. M., F. R. Cole, L. E. Helgen, and D. E. Wilson. 2009. Generic revision in the Holarctic ground squirrel genus Spermophilus. Journal of Mammalogy, 90:270-305.
- 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.
