Least chipmunk

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Least chipmunk
Tamias minimus.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Sciuridae
Genus: Neotamias
Species:
N. minimus
Binomial name
Neotamias minimus
(Bachman, 1839)
Tamias minimus distribution map.png
Distribution of the least chipmunk
Synonyms
  • Tamias minimus
  • Eutamias minimus

The least chipmunk (Neotamias minimus) is the smallest species of chipmunk [2] and the most widespread in North America.

Description

It is the smallest species of chipmunk, measuring about 15.7–25 cm (6.2–9.8 in) in total length with a weight of 25–66 g (0.88–2.33 oz). [3] The body is gray to reddish-brown on the sides, and grayish white on the underparts. The back is marked with five dark brown to black stripes separated by four white or cream-colored stripes, all of which run from the nape of the neck to the base of the tail. Two light and two dark stripes mark the face, running from the tip of the nose to the ears. The bushy tail is orange-brown in color, and measures 10–11 cm (3.9–4.3 in) long. [4] In some areas, where range overlap with the yellow-pine chipmunk occurs, it may be difficult or impossible to distinguish the two species in the field; laboratory examination of skeletal structures may be required. [5]

As in other chipmunks, there are four toes on each of the forefeet and five on the hindfeet. Females have eight teats. The brain to body mass ratio for least chipmunks is lower than that for other species of chipmunk living in the same area, suggesting that they prefer less complex environments. [6]

Distribution and habitat

Least chipmunks are found through most of the western United States from northern New Mexico and western North and South Dakota to eastern California, Oregon and Washington, and throughout much of southern and western Canada from Yukon and southeastern British Columbia [7] to central Ontario, and into the Upper Peninsula of Michigan and neighboring parts of Wisconsin and Minnesota. Throughout this range, as many as 21 subspecies have been identified. [4] Less arboreal than other chipmunks, [4] least chipmunks are commonly found in sagebrush habitats and coniferous woodland, and along rivers, but they also occur in alpine meadows, and on the edges of the northern tundra. [1]

Behavior

Least chipmunks are diurnal and eat seeds, berries, nuts, fruits and insects. They mark areas depleted of suitable food with urine, and do not return to such patches afterwards. [8] Home ranges vary widely, and have been reported to vary from 0.1 ha (0.25 acres) in northern Michigan [4] to as much as 5.5 ha (14 acres) in Colorado. [9] Because of their small size, least chipmunks are generally subordinate to yellow-pine chipmunks, which are able to drive them away from food resources where food is plentiful. However, because they need to eat less food in order to survive, least chipmunks are more numerous where resources are scarce. [10] They are agile animals, and have been recorded running at speeds of up to 7.7 km/h (4.8 mph) in natural conditions. [11]

Predators include hawks, owls, and mustelids.[ citation needed ]

Least chipmunks spend the winter in burrows and also scatter-hoard food in numerous concealed pits beneath logs and similar cover. Burrows consist of a single chamber about 15 cm (5.9 in) across and tunnels 7.5 cm (3.0 in) in diameter, averaging 1.7 m (5 ft 7 in) in length. They have two to four entrances, often concealed by nearby rocks, and are typically about 18 cm (7.1 in) below the surface. [4] During the summer they may construct temporary nests in trees from leaves and grass, [12] or appropriate hollows made by woodpeckers. [4]

Least chipmunks do not hibernate, or put on excess fat in the fall. Instead, they survive the winter by entering torpor for long stretches of time, waking to eat food cached in the burrow. How much of each winter they spend below ground in this manner depends on the latitude, varying from late November to mid March in Michigan to mid October to late April in northern Manitoba. [4]

Reproduction

Females enter estrus within a week of emerging from their burrow in the spring, and mating typically takes place between March and May. Gestation lasts 28 to 30 days, with a single litter of three to seven young being born each year; females who lose their first litter soon after birth may, however, sometimes be able to breed again in the same year. The young are born hairless and blind, measuring about 5 cm (2.0 in) in length, and weighing 6 g (0.21 oz). They are able to stand and open their eyes at 27 days, and are weaned at 36 days. They are sexually mature at one year, but do not always breed until their second year. They can live for up to six years in captivity. [4]

Related Research Articles

<span class="mw-page-title-main">Chipmunk</span> Tribe of mammals (rodent (marmot))

Chipmunks are small, striped rodents of Sciuridae, the squirrel family; specifically, they are ground squirrels (Marmotini). Chipmunks are found in North America, with the exception of the Siberian chipmunk which is found primarily in Asia.

<span class="mw-page-title-main">Ground squirrel</span> Type of ground-dwelling rodent

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 are more commonly known as marmots or prairie dogs, while the smaller and less bushy-tailed ground squirrels tend to be known as chipmunks.

<span class="mw-page-title-main">Desert woodrat</span> Species of rodent

The desert woodrat is a species of pack rat native to desert regions of western North America.

<span class="mw-page-title-main">Siberian chipmunk</span> Species of mammal

The Siberian chipmunk, also called common chipmunk, is native to northern Asia from central Russia to China, Korea, and Hokkaidō in northern Japan. It was imported from South Korea and introduced in Europe as a pet in the 1960s.

<span class="mw-page-title-main">Alpine chipmunk</span> Species of rodent

The alpine chipmunk is a species of chipmunk native to the high elevations of the Sierra Nevada of California.

<span class="mw-page-title-main">Yellow-pine chipmunk</span> Species of rodent

The yellow-pine chipmunk is a species of order Rodentia in the family Sciuridae. It is found in parts of Canada and the United States.

<span class="mw-page-title-main">Gray-footed chipmunk</span> Species of rodent in the family Sciuridae

The gray-footed chipmunk is a terrestrial and forest-dwelling species of chipmunk and rodent in the family Sciuridae. It is endemic to New Mexico and in the Sierra Diablo and Guadalupe Mountains in the Trans-Pecos region of Texas in the United States. Its natural habitat are coniferous forests. First discovered in 1902, they are distinguished by the unique gray dorsal colouring on the hind feet, hence the common name. They demonstrate sexual dimorphism, and the female is larger than the male.

<span class="mw-page-title-main">Gray-collared chipmunk</span> Species of rodent

The gray-collared chipmunk is a species of rodent in the family Sciuridae. It is endemic to Arizona and New Mexico in the United States.

<span class="mw-page-title-main">Merriam's chipmunk</span> Species of rodent

Merriam's chipmunk is a species of rodent in the family Sciuridae. It is found in central and southern California in the United States and a small area in northern Baja California, Mexico.

<span class="mw-page-title-main">Yellow-cheeked chipmunk</span> Species of rodent

The yellow-cheeked chipmunk, also known as the redwood chipmunk, is a species of rodent in the squirrel family, Sciuridae. It is endemic to areas near the coast of northern California in the United States where it inhabits coastal coniferous forest.

<span class="mw-page-title-main">Palmer's chipmunk</span> Species of rodent

Palmer's chipmunk is a species of rodent in the family Sciuridae, endemic to Nevada. Its natural habitat is temperate forests. It is threatened by habitat loss. It is named after Theodore Sherman Palmer, an American botanist and zoologist.

<span class="mw-page-title-main">Colorado chipmunk</span> Species of rodent

The Colorado chipmunk is a species of chipmunk in the squirrel family Sciuridae. It is endemic to Colorado, Utah, Arizona and New Mexico in the United States.

<span class="mw-page-title-main">Red-tailed chipmunk</span> Species of rodent

The red-tailed chipmunk is a species of rodent in the family Sciuridae. It is found in Alberta and British Columbia in Canada and Montana, Idaho and Washington in the United States.

<span class="mw-page-title-main">Allen's chipmunk</span> Species of rodent

Allen's chipmunk, also known as the shadow chipmunk, is a species of chipmunk native to the western United States. Occurring in California, Oregon, and Nevada, it is a common species of the Sierra Nevada.

The Siskiyou chipmunk is a species of rodent in the family Sciuridae. It is endemic to northern California and central Oregon in the United States.

<span class="mw-page-title-main">Sonoma chipmunk</span> Species of rodent

The Sonoma chipmunk is a species of rodent in the squirrel family Sciuridae. It is endemic to northwestern California in the United States. Members of Neotamias are characterized by having two premolars. N. sonomae has two subspecies: N. s. alleni and N. s. sonomae.

<span class="mw-page-title-main">Lodgepole chipmunk</span> Species of rodent

The Lodgepole chipmunk is a species of rodent in the family Sciuridae. It is found in the U.S. state of California at elevations from 1,500 to 3,000 metres. The Lodgepole chipmunk has a variety of common names including: Tahoe chipmunk, Sequoia chipmunk, Mt. Pinos chipmunk, and San Bernardino chipmunk.

<span class="mw-page-title-main">Uinta chipmunk</span> Species of rodent

The Uinta chipmunk or hidden forest chipmunk, is a species of chipmunk in the family Sciuridae. It is endemic to the United States. Formerly known as Tamias umbrinus, phylogenetic studies have shown it to be sufficiently distinct from the eastern chipmunk as to be placed in a separate genus, Neotamias. The same studies have also suggested that Palmer's chipmunk may actually be a subspecies of Uinta chipmunk, although the two are still generally regarded as separate species.

<i>Neotamias</i> Genus of rodents

Neotamias is a genus of chipmunks within the tribe Marmotini of the squirrel family. It contains 23 species, which mostly occur in western North America. Along with Eutamias, this genus is often considered a subgenus of Tamias.

<span class="mw-page-title-main">Ezo chipmunk</span> Subspecies of mammal

The Ezo chipmunk is a subspecies or local population of the Siberian chipmunk; it is found in what was once known as Ezo, namely Hokkaidō, Japan, and Sakhalin and the Southern Kuriles, Russia.

References

  1. 1 2 Cassola, F. (2017) [errata version of 2016 assessment]. "Neotamias minimus". IUCN Red List of Threatened Species . 2016: e.T42572A115190804. doi: 10.2305/IUCN.UK.2016-3.RLTS.T42572A22267269.en . Retrieved 19 February 2022.
  2. William Henry Burt (1980). A Field Guide to the Mammals: North America North of Mexico. Houghton Mifflin Harcourt. pp. 110–. ISBN   0-395-91098-6.
  3. Least chipmunk (Tamias minimus) Archived 2013-10-15 at the Wayback Machine , Arkive
  4. 1 2 3 4 5 6 7 8 Verts, B.J.; Carraway, L.N. (2001). "Tamias minimus" (PDF). Mammalian Species. 653: 1–10. doi:10.1644/1545-1410(2001)653<0001:tm>2.0.co;2. S2CID   36836203. Archived from the original (PDF) on 2015-06-06.
  5. Naughton, Donna (2012). The Natural History of Canadian Mammals. Canadian Museum of Nature and University of Toronto Press. p. 60. ISBN   978-1-4426-4483-0.
  6. Budeau, D.A.; Verts, B.J. (1986). "Relative brain size and structural complexity of habitats of chipmunks". Journal of Mammalogy. 67 (3): 579–581. doi:10.2307/1381291. JSTOR   1381291.
  7. Nagorsen, David W. (2005). Rodents & lagomorphs of British Columbia. The mammals of British Columbia. Victoria: Royal BC Museum. ISBN   978-0-7726-5232-4. OCLC   60669537.
  8. Devenport L, et al. (1999). "The role of urine marking in the foraging behaviour of least chipmunks". Animal Behaviour. 57 (3): 557–563. doi:10.1006/anbe.1998.1026. PMID   10196045. S2CID   33186159.
  9. Bergstrom, B.J. (1988). "Home ranges of three species of chipmunks (Tamias) as assessed by radiotelemetry and grid trapping". Journal of Mammalogy. 69 (1): 190–193. doi:10.2307/1381774. JSTOR   1381774.
  10. Sheppard, D.H. (1971). "Competition between two chipmunk species (Eutamias)". Ecology. 52 (2): 320–329. doi:10.2307/1934591. JSTOR   1934591.
  11. Smith, R.J. (1995). "Harvest rates and escape speeds in two coexisting species of montane ground squirrels". Journal of Mammalogy. 76 (1): 189–195. doi:10.2307/1382327. JSTOR   1382327.
  12. Broadbrooks, H.E. (1974). "Tree nests of chipmunks with comments on associated behavior and ecology". Journal of Mammalogy. 55 (3): 630–639. doi:10.2307/1379551. JSTOR   1379551.