Last modified on 6 March 2013, at 21:41

Field Guide/Mammals/Gray Fox

urocyon cineroargenteus (Grey Fox)
Family: Canidae
Size: 76-112.5 cm (30-44.3 inches) in total length. Weighs approximately 3.6-7 kg (7.9-15 lbs.) Male and Females look the same except females may be slightly smaller in size than male counterparts.
Description: The gray fox is medium sized with a stocky body, moderately short legs and medium-sized ears. It can be distinguished from the grizzled grey and red coat with dark points around the nose top of the head and back with a black tipped tail. The undercoat is gray. The Grey fox can be distinguished from other candid's by its widely separated temporal ridges which create a U shape.[1]

Range: The gray fox is widespread in forest, woodland, brushland, shrubland, and rocky habitats in temperate and tropical regions of North America, and in northern regions of South America.
Habitat: In eastern North America, the gray fox is most commonly lives where there are deciduous/southern pine forests interspersed with some old fields and woodlands. In western North America, it is commonly found in mixed agricultural/woodland landscapes, and shrub habitats. The species occupies forested areas and thick brush habitats in Central America, and forested montane habitats in South America. They may also occur in semi-arid areas of the south-western U.S. and northern Mexico where cover is sufficient.[2]
Diet: The gray fox is a solitary hunter and is primarily omnivorous. It will readily prey upon the eastern cottontail, voles, shrews, and birds in the eastern United States. In California, the gray fox primarily eats rodents, followed by other rabbit species such as jack rabbit, and the brush rabbit. In some parts of the Western United States the gray fox is primarily insectivorous and herbivorous. Fruit is also an important component of urocyon cinereogenteus’s diet and they seek whatever fruits are readily available, generally eating more vegetable matter and is therefore more omnivorous than any other fox species[3]
Activity: Grey foxes are nocturnal creatures meaning that they are primarily do their hunting/ foraging at night and dens in hollow trees, stumps or burrows during the day. Its ability to climb trees is shared only with the Asian Raccoon dog among canids. The grey fox has strong, hooked claws that allow it to climb up trees to escape predators such as the domestic dog or the coyote or to reach arboreal food sources. It descends primarily by jumping from branch to branch, or by descending slowly backwards as a house cat would do.[4]

Reproduction: During parturition and pup rearing, gray foxes use earthen dens, either dug themselves or modified from burrows of other species. They will also den in wood and brush piles, rock crevices, hollow logs, hollows under shrubs, and under abandoned buildings. Gray foxes may even den in hollows of trees up to nine meters above the ground. Den use diminishes greatly during non- reproductive seasons when gray foxes typically use dense vegetation for diurnal resting locations. Gray foxes reach sexual maturity at 10 months of age, although not all females breed in their first year. Breeding typically occurs from January to April with gestation lasting about 60 days. Litter size ranges from 1–10 and averages around four pups. Eyes of pups open at about 10–12 days. Pups accompany adults on foraging expeditions at three months and forage independently at four months. Females appear to be responsible to provision pups, although there is some evidence that males may also contribute to care of pups. Juveniles reach adult size and weight at about 210 days.[5]
Lifespan: It is rare for a gray fox to live longer than 4–5 years, although it has been reported that some individuals could live 14–15 years if kept in proper conditions in captivity.

Notes: The Grey Fox is unique from other candids because of the fact that they can climb trees easily using their back legs to quickly propel themselves up tree trunks. This unique behavior characteristic has given them the nicknames "tree fox" and "racoon dog". While their fur in the past has some value for fur trade, because of their duller gray coat color,grey foxes were never as highly sought after for fur trade as the red fox.
urocyon cineroargenteus Grey Fox

  1. "Urocyon Cinereoargenteus", Mammalian Species (189): 283-294., 1979, http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/i0076-3519-189-01-0001.pdf, retrieved October 10, 2012 
  2. "Urocyon Cinereoargenteus", Mammalian Species (189): 283-294., 1979, http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/i0076-3519-189-01-0001.pdf, retrieved October 10, 2012 
  3. [:http://www.iucnredlist.org/details/22780/0 Urocyon Cinereoargenteus], 2011,
    http://www.iucnredlist.org/details/22780/0, retrieved October 10, 2012 
  4. [:http://www.iucnredlist.org/details/22780/0 Urocyon Cinereoargenteus], 2011,
    http://www.iucnredlist.org/details/22780/0, retrieved October 10, 2012 
  5. "Grey Fox", Canids: Foxes, Wolves, Jackals, and Dogs: 92-98., 1982, http://www.carnivoreconservation.org/files/actionplans/canids.pdf, retrieved October 10, 2012