Arizona gray squirrel

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Arizona gray squirrel
Arizona Gray Squirrel Sciurus arizonensis.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. arizonensis
Binomial name
Sciurus arizonensis
Coues, 1867
Subspecies [2]
  • S. a. arizonensis
  • S. a. catalinae
  • S. a. huachuca
Sciurus arizonensis range map.svg
Arizona gray squirrel range

The Arizona gray squirrel (Sciurus arizonensis) 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.

It is threatened by habitat loss. The only other large squirrel that is within its range is Abert's squirrel, which has ear tufts and lives in pine forests. Although they act and look like other gray squirrels, the Arizona gray squirrel is actually more closely related to the fox squirrel.

Phylogeny and description

Sciurus arizonensis is a member of the order Rodentia and the family Sciuridae. It is distinguishable from Sciurus aberti by its longer flatter skull, broader rostrum, and having only one molar instead of two. S. arizonensis also has smaller ears with no tufts and a red/black stripe on the underside of their tail. Some sexual dimorphism can be seen in these squirrels, but it varies with some populations having larger males, and other populations having larger females. [3]

Distribution and habitat

Sciurus arizonensis or the Arizona gray squirrel can be found in parts of Arizona, New Mexico and Sonora, Mexico. [3] They live in the mountains [4] at mid-elevations in riparian habitats, usually broadleaf riparian habitats. [5] The Arizona gray squirrel has had no recent expansion or reduction in the size of their range in New Mexico, though there has been some population decline. This is due to habitat loss and the introduction of Abert’s squirrel, which has in some cases outcompeted the Arizona gray squirrel for resources. [5]

Diet

The Arizona gray squirrel's diet consists mainly of pine cones, acorns, and other nuts. They also eat seeds and berries.

Reproduction

Arizona gray squirrels have large variations in their diet, which has led to reproduction rates that vary year by year. Not all females breed each year, which can be seen by a lack of placental scarring. The timing of Arizona gray squirrel mating correlates with the prime time for flowers, which are a high energy food source for the energetically expensive costs of mating. [3] Because mating is so energetically expensive, optimal reproduction timing is very important to ensure that offspring and parent will survive. This timing can differ between sexes and is largely dependent on the environmental change present in their habitat, which can often be fluctuating throughout the year and from year to year. [6] Differences in the parental investment and a lack of food are responsible for shifts in male and female ranges. The opposite sexes have ranges that overlap with each other and during good mating conditions or season these ranges will expand and overlap more. [7] These squirrels have been observed in mating chases with many males chasing one female. [3] An important conservation strategy for the survival of the Arizona gray squirrel is to protect their nesting habitat. This means maintaining large trees with closed canopies that allow access to resources and protection from predators. [3]

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">Eastern gray squirrel</span> Tree squirrel native to eastern and central North America

The eastern gray squirrel, also known, particularly outside of North America, as simply the grey squirrel, is a tree squirrel in the genus Sciurus. It is native to eastern North America, where it is the most prodigious and ecologically essential natural forest regenerator. Widely introduced to certain places around the world, the eastern gray squirrel in Europe, in particular, is regarded as an invasive species.

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

The fox squirrel, also known as the eastern fox squirrel or Bryant's fox squirrel, is the largest species of tree squirrel native to North America. Despite the differences in size and coloration, it is sometimes mistaken for American red squirrels or eastern gray squirrels in areas where the species co-exist.

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

The American red squirrel is one of three species of tree squirrels currently classified in the genus Tamiasciurus, known as the pine squirrels. The American red squirrel is variously known as the pine squirrel or piney squirrel, North American red squirrel, chickaree, boomer, or simply red squirrel. The squirrel is a small, 200–250 g (7.1–8.8 oz), diurnal mammal that defends a year-round exclusive territory. It feeds primarily on the seeds of conifer cones, and is widely distributed across much of the United States and Canada wherever conifers are common, except in the southwestern United States, where it is replaced by the formerly conspecific southwestern red squirrel, and along the Pacific coast of the United States, where its cousin the Douglas squirrel is found instead.

<i>Sciurus</i> Genus of rodents

The genus Sciurus contains most of the common, bushy-tailed squirrels in North America, Europe, temperate Asia, Central America and South America.

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

Abert's squirrel or the tassel-eared squirrel is a tree squirrel in the genus Sciurus native to the southern Rocky Mountains from the United States to the northern Sierra Madre Occidental of Mexico, with concentrations found in Arizona, New Mexico, and southwestern Colorado. It is closely associated with, and largely confined to, mature ponderosa pine forests. It is named in honor of the American naturalist John James Abert; nine subspecies are recognised. It is recognizable by its tufted ears, gray color, pale underparts and rufous patch on the lower back. The squirrel feeds on the seeds and cones of the Mexican pinyon and the ponderosa pine when they are available, but will also take fungi, buds, bark, and carrion. Breeding normally occurs in summer, with a spherical nest being built high in the canopy.

<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">Pallid bat</span> Species of bat

The pallid bat is a species of bat that ranges from western Canada to central Mexico. It is the sole species of its genus and is closely related to Van Gelder's bat, which is sometimes included in Antrozous. Although it has in the past been placed in its own subfamily (Antrozoinae) or even family (Antrozoidae), it is now considered part of the subfamily Vespertilioninae and the tribe Antrozoini.

<span class="mw-page-title-main">Brush mouse</span> Species of rodent

The brush mouse is a species of rodent in the family Cricetidae. It is found in mountainous areas of Mexico and the western United States at altitudes over 2,000 m (6,600 ft).

<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.

The common yellow-toothed cavy is a species of rodent in the family Caviidae, closely related to the domesticated guinea pig. It is found in Argentina, Bolivia, Chile, and Peru. Its karyotype has 2n = 68 and FN = 136. G. musteloides is the most common and widely found member of Galea, and is present at elevations ranging from 20 to 5000 m above sea level. It has yellow teeth.

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

The Santander dwarf squirrel is a small tree squirrel endemic to Colombia.

<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">Mexican fox squirrel</span> Species of rodent

The Mexican fox squirrel 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.

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

Richmond's squirrel is a poorly known tree squirrel in the genus Sciurus endemic to Nicaragua, which is likely a synonym of the red-tailed squirrel. It is locally known as the ardilla del rama.

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

The Mexican ground squirrel is a species of rodent in the family Sciuridae. It is found in Mexico and the United States. One of its closest relatives is the thirteen-lined ground squirrel.

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

The rock squirrel is a species of rodent in the family Sciuridae. It is native to Mexico and the Southwestern United States, including southern Nevada, Utah, Colorado, Arizona, New Mexico, West Texas, and the panhandle of Oklahoma.

<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.

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

Sherman's fox squirrel is a subspecies of the fox squirrel. It lives in the U.S. states of Florida and Georgia in fire-prone areas of longleaf pine and wiregrass, especially around sandhills. A tree squirrel, Sherman's fox squirrel has lost much of its habitat to farming and development. This type of squirrel nests in oak trees using leaves and Spanish moss.

References

  1. Linzey, A.V.; Timm, R.; Álvarez-Castañeda, S.T.; Castro-Arellano, I.; Lacher, T. (2019). "Sciurus arizonensis". IUCN Red List of Threatened Species . 2019: e.T20005A22247935. doi: 10.2305/IUCN.UK.2019-3.RLTS.T20005A22247935.en . Retrieved 12 November 2021.
  2. Thorington, R.W. Jr.; Hoffmann, R.S. (2005). "Sciurus (Sciurus) arizonensis". 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   0-8018-8221-4. OCLC   26158608.
  3. 1 2 3 4 5 Best, Troy L. (June 23, 1995). "Sciurus arizonensis". Mammalian Species (496): 1–5. doi: 10.1644/0.496.1 . JSTOR   3504161. S2CID   253925558.{{cite journal}}: Unknown parameter |agency= ignored (help)
  4. Cudworth, Nichole L.; Koprowski, John. L. (September 2011). "Importance of Scale in Nest-Site Selection by Arizona Gray Squirrels". The Journal of Wildlife Management. 75 (7): 1668–1674. Bibcode:2011JWMan..75.1668C. doi:10.1002/jwmg.194. JSTOR   41418210. S2CID   53688725.
  5. 1 2 Frey, Jennifer K.; Hill, Michael T.; Christman, Bruce L.; Truett, Joe C.; MacDonald, Stephen O. (June 2008). "Distribution and Habitat of the Arizona Gray Squirrel (Sciurus arizonensis) in New Mexico". The Southwestern Naturalist. 53 (2): 248–255. doi:10.1894/0038-4909(2008)53[248:dahota]2.0.co;2. JSTOR   20424923. S2CID   85657187.
  6. Cudworth, Nichole L.; Koprowski, John L. (11 June 2013). "Foraging and reproductive behavior of Arizona gray squirrels (Sciurus arizonensis): impacts of climatic variation". Journal of Mammalogy. 94 (3): 683–690. doi: 10.1644/12-mamm-a-087.1 .
  7. Cudworth, Nichole L.; Korowski, John. L. (October 2010). "Influences of mating strategy on space use of Arizona gray squirrels". Journal of Mammalogy. 91 (5): 1235–1241. doi:10.1644/09-mamm-a-426.1. JSTOR   40925730. S2CID   53680929.