Mexican fox squirrel

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Mexican fox squirrel
Chiricahua fox squirrel.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Rodentia
Family: Sciuridae
Genus: Sciurus
Species:
S. nayaritensis
Binomial name
Sciurus nayaritensis
Subspecies [2]
  • S. n. nayaritensis - Nayarit fox squirrel
  • S. n. apache - Apache fox squirrel
  • S. n. chiricahuae - Chiricahua fox squirrel
Mexican fox squirrel range map.png
Mexican fox squirrel's range

The Mexican fox squirrel (Sciurus nayaritensis) is a species of tree squirrel found throughout the Sierra Madre Occidental of Mexico as far south as Jalisco — and northward into the Chiricahua Mountains of southeastern Arizona, U.S. [3]

This species, or its subspecies, is sometimes called the Nayarit, Apache, or Chiricahua fox squirrel. [3] It has been evaluated as an IUCN Red List Least Concern species.

Description

Physical

The Mexican fox squirrel has a grizzled brown back with a yellow to rufous underside, and a charcoal tail frosted with white. Two molts occur each year; the winter pelage is more rufous and the scrotum is often ringed with white. [4] Mass is approximately 700 grams (25 oz). [5]

Behavior

Mexican fox squirrels are diurnal, non-territorial, [6] and do not hibernate during the winter months. [7]

Food sources

The Mexican fox squirrel forages extensively on the ground and in the forest canopy for tree seeds, flowers, and fungi. Seeds from the cones from pine, Douglas fir, and true firs are extracted by removing individual cone scales. Acorns and walnuts are also eaten when available, along with a variety of other tree seeds, hypogeous and occasionally epigeous fungi, and insects. [8] Mexican fox squirrels occasionally cache large seeds by scatter-hoarding them in leaf litter and topsoil. [4]

The ecology of the Mexican fox squirrel has not been studied thoroughly, particularly outside the United States. Densities are often very low. [9] Large raptors, canids, felids, procyonids and snakes are likely the major predators. [10]

Mexican fox squirrels typically produce a single small litter of 1 or 2 young in late spring or summer. [9] Mexican fox squirrels nest in ball-shaped dreys composed of sticks and leaves in trees; cavities within large trees are occasionally used, especially by nursing females. They are known to communally nest at times. Mexican fox squirrels are notably silent and appear to prefer to seek cover and remain motionless. If startled, they may bark and chuck from safe locations in trees. [4]

Habitat

Mexican fox squirrels are found in forests ranging from low elevation (~1,500 metres [ 4,900 ft ]) Madrean forests with a mixture of pine and oak to higher elevation mixed conifer forests < 2,700 metres [ 8,900 ft ]. [11] Riparian areas with large cottonwoods and sycamores often harbor the highest densities. In the United States, the squirrel lives only in the Chiricahua Mountains of southeastern Arizona. [12]

The Mexican fox squirrel inhabits forests that were historically maintained by frequent, low-severity fire, and uses areas with open understory and large trees that are typical of such forests. [13]

Subspecies

There are three subspecies: [4]

See also

Related Research Articles

<span class="mw-page-title-main">Sciurinae</span> Subfamily of rodents

Sciurinae is a subfamily of squirrels, uniting the flying squirrels with certain related tree squirrels. Older sources place the flying squirrels in a separate subfamily (Pteromyinae) and unite all remaining sciurids into the subfamily Sciurinae, but this has been strongly refuted by genetic studies.

<span class="mw-page-title-main">Western gray squirrel</span> Species of rodent

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<span class="mw-page-title-main">Fox squirrel</span> Species of mammal

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<span class="mw-page-title-main">American red squirrel</span> Species of pine squirrel found in North America

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<i>Sciurus</i> Genus of rodents

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

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<span class="mw-page-title-main">Bolivian squirrel</span> Species of rodent

The Bolivian squirrel is a tree squirrel that is endemic to South America. Little is known of the species, which may represent a species complex.

<span class="mw-page-title-main">Amazon dwarf squirrel</span> Species of rodent

The Amazon dwarf squirrel is a chipmunk-sized tree squirrel native to South America.

<span class="mw-page-title-main">Mexican gray squirrel</span> Species of rodent

The Mexican gray squirrel is a tree squirrel in the genus Sciurus native to Guatemala and eastern and southern Mexico. It has been introduced to the Florida Keys.

<span class="mw-page-title-main">Caucasian squirrel</span> Species of rodent

The Caucasian squirrel or Persian squirrel, is a tree squirrel in the genus Sciurus found in temperate broadleaf and mixed forests in south-western Asia.

<span class="mw-page-title-main">Arizona gray squirrel</span> Species of rodent

The Arizona gray squirrel is a tree squirrel, in the genus Sciurus, endemic to the canyons and valleys surrounded by deciduous and mixed forests in eastern Arizona and northern Mexico.

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

Collie's squirrel is a tree squirrel in the genus Sciurus endemic to Mexico.

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

Deppe's squirrel is a species of tree squirrel in the genus Sciurus native to Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua.

<span class="mw-page-title-main">Fiery squirrel</span> Species of rodent

The fiery squirrel is a rodent in the family Sciuridae. The taxon is endemic to the area south of the Orinoco River in the state of Bolívar, Venezuela.

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

Peters's squirrel is a tree squirrel in the genus Sciurus endemic to Mexico. It was first described by the German naturalist and explorer Wilhelm Peters in 1863. Three subspecies are recognised. It is a common species, and the IUCN has rated its conservation status as being of "least concern".

Sanborn's squirrel is or was a little known tree squirrel described in 1944 from the skin and skeleton of a single female specimen collected in Peru in 1941. Subsequently, over the proceeding years only a handful of either specimens were collected, or observations were recorded, in the regions of Madre de Dios and northern Puno in Peru, and Pando department in Bolivia. The 2019 IUCN assessment describes it as endemic to Peru. In 2015 this taxon was synonymised with Notosciurus pucheranii ssp. boliviensis. Its habitat is tropical dry broadleaf forests at elevations up to 570 m. It is considered possibly rare and potentially vulnerable to deforestation, but its population trend is not established.

<span class="mw-page-title-main">Variegated squirrel</span> Species of rodent

The variegated squirrel is a tree squirrel in the genus Sciurus found in Costa Rica, El Salvador, Guatemala, Honduras, southern Mexico, Nicaragua, and Panama. Fifteen subspecies are recognised. It is a common squirrel and the International Union for Conservation of Nature has rated it a "least-concern species". Variegated squirrels kept as pets in Germany have been implicated in the transmission of a bornavirus to humans from which three people have died.

<span class="mw-page-title-main">Yucatan squirrel</span> Species of rodent

The Yucatan squirrel, originally named the Yucatan gray squirrel, also once named the Campeche squirrel, is a tree squirrel in the genus Sciurus found in the Yucatán Peninsula and adjacent areas. It is native to northern Belize, northeastern Guatemala, and southeast Mexico.

<span class="mw-page-title-main">Mearns's squirrel</span> Subspecies of rodent

Mearns's squirrel is a subspecies of the Douglas squirrel endemic to Mexico. It is endangered and occurs in low densities, and is threatened by habitat loss. It is possibly also threatened by competition from the eastern gray squirrel, which was introduced to the range of Mearns's squirrel in 1946, but may not be present anymore. It is closely related to other subspecies of the Douglas squirrel, but far less is known about its behavior, which was first studied in detail in 2004. It is named for the 19th-century American naturalist Edgar Mearns.

<span class="mw-page-title-main">John L. Koprowski</span> American biologist

John L. Koprowski, Dean and Professor, Haub School of Environment & Natural Resources, University of Wyoming, mammalogist, conservation biologist, and leading expert on the ecology and conservation of wildlife, especially squirrels, was born in 1961 in Lakewood, Ohio.

References

  1. Linzey, A. V.; Koprowski, J. & Roth, L. (2008). "Sciurus nayaritensis". IUCN Red List of Threatened Species . 2008. Retrieved 6 January 2009.
  2. Thorington, R.W. Jr.; Hoffmann, R.S. (2005). "Family Sciuridae". In Wilson, D.E.; Reeder, D.M (eds.). Mammal Species of the World: a taxonomic and geographic reference (3rd ed.). The Johns Hopkins University Press. pp. 754–818. ISBN   978-0-8018-8221-0. OCLC   26158608.
  3. 1 2 Best, T.L. (1995) Sciurus nayaritensis. Mammalian Species 492, 1-5.
  4. 1 2 3 4 Thorington, R.W., Jr., Koprowski, J.L., Steele, M.A., and Whatton, J. (2012) Squirrels of the World. Johns Hopkins University Press, Baltimore, 472 pp.
  5. Pasch, B.S., Koprowski, J.L. (2006a) Annual cycles in body mass and reproduction of Chiricahua fox squirrels (Sciurus nayaritensis chiricahuae). Southwest. Nat. 51, 531-535.
  6. Pasch, B.S., Koprowski, J.L. (2006b) Sex differences in space use of Chiricahua fox squirrels. J. Mammal. 87, 380-386.
  7. Koprowski, J.L., Corse, M.C. (2005) Time budgets, activity periods, and behavior of Mexican fox squirrels. J. Mammal. 86, 947-952.
  8. Koprowski, J.L., Corse, M.C. (2001) Food habits of the Chiricahua fox squirrel (Sciurus nayaritensis chiricahuae). Southwest. Nat. 46, 62-65.
  9. 1 2 Pasch, B.S., Koprowski, J.L. (2005) Correlates of vulnerability in Chiricahua fox squirrels, in: Gottfried, G.J., Gebow, B.S., Eskew, L.G., Edminster, C.B. (Eds.), Proceedings: Connecting mountain islands and desert seas: biodiversity and management of the Madrean archipelago II. USDA Forest Service, Gen. Tech. Rep. RMRS-P-36, Rocky Mountain Research Station, Fort Collins, CO, pp. 426-428.
  10. Kneeland, M.C., Koprowski, J.L., and Corse, M.C. (1995) Potential predators of chiricahua fox squirrels (Sciurus nayaritensis chiricahuae). Southwest. Nat. 40, 340-342.
  11. Hoffmeister, D.F. (1986) Mammals of Arizona. The University of Arizona Press, pp. 212-213.
  12. Brown, D.E. (1984) Arizona's tree squirrels. Arizona Game and Fish Department, pp. 39-61.
  13. Doumas, Sandra L.; Koprowski, John L. (2013). "Return of Fire as a Restoration Tool: Long-Term Effects of Burn Severity on Habitat Use by Mexican Fox Squirrels". Restoration Ecology. 21: 133–139. doi:10.1111/j.1526-100X.2012.00864.x. S2CID   53664867.