SUNY ESF
Gray Fox
Grizzled gray upperparts, a blackish band on each side of the muzzle, and a black-tipped tail are some of the characters by which the gray fox differs from the red fox. Other differences include coarser fur, a shorter muzzle and legs, dark brown eyes, and a mane of stiff, black hairs on the dorsal surface, or on top, of the tail. The gray fox has a white throat and belly. The chest and lower sides of the body, undersurface of the tail, backs of the ears, parts of the legs, feet and neck are reddish or yellowish brown. The claws are sharp, and on the forefeet recurved. Adults are 89-105 cm (35.0-41.3 in) in length. The tail comprises about one- third of this length. Weight varies from 3.2-6.4 kg (7-14 lbs); males are slightly heavier than females.
(Urocyon cinereoargentues Schreber)
From: Saunders, D. A. 1988. Adirondack Mammals. State University of New York, College of Environmental Science and Forestry. 216pp.
Order: Carnivora
Family: Canidae
Range and Habitat
The range is from the northern tip of South America northward to the extreme southern portions of the eastern Canada, and to the Great Basin and northern Rocky Mountains in the western U.S. The gray fox is a relatively common and wide-spread resident of the Adirondack Park, occurring to elevations of at least 915 m (3000 ft) (Mark Brown, pers. Comm.), but is less abundant that the red fox. The earliest record of the gray fox in the Adirondacks are from the present century, especially the period, 1930-40. These records reflect a general northern expansion of the range of the gray fox that began about 1900. Archaeological evidence, however, suggests that the gray fox was formerly present throughout New York State.
Unlike the red fox which prefers forest openings, meadows, and farmlands, the gray fox favors deciduous forests and brushy, rocky woodlands, but inhabits mixed forests and forest-farmland edges as well. These habitats are most abundant in the lowlands, lower elevations, and periphery of the Adirondack Park.
The gray fox may rest in the open ar in dens located in the abandoned barrows of other mammals, but are more often in hollow logs and trees, brush piles, and under or among rocks. Dens may contain bedding of the feathers and fur of prey, shredded bark, dried leaves and grass.
Food and Feeding Behavior
The diet of this opportunistic omnivore reflects the seasonal abundance of small to medium-sized mammals, birds and their eggs, large seeds, fruits, insects, reptiles and amphibians. Cottontails, mice, and voles are major prey items. The gray fox, which forages on the ground and in trees, consumes a greater amount of fruit and birds than the red fox.
Activity and Movement
The gray fox is active throughout the year, and leaves its den at twilight or night to forage, but may hunt during the day, too. The usual manner of travel is by walking or trotting, but when necessary, a gray fox gallops or runs, attaining a top speed of 32.2-45.1 km/h (20-28 mph). Unlike the red fox, this species frequently ascends trees by leaping into branches near the ground, or by shinnying up trunks. The back legs power the climb as the front limbs reach upward to grasp the bark. After climbing a tree, a gray fox may leap or hop from one branch to another, eventually descending by backing or running down the trunk head first. Arboreal activities, besides searching for prey, include escaping danger, sunning and entering dens.
Reproduction
Gray foxes mate from late January to May, with the peak of breeding occurring in March. The gestation period is 51-63 days (average 53 days). The female bears an annual litter of 2-7 (average 3-5). Most litters are born in late March or April. The newborn are blind, weigh approximately 86g (3 oz), and are covered with fine textured black fur. The eyes open at 9-12 days; weaning takes place at 56-70 days. At 3 months of age, the young leave the den to hunt with the female, and by four months of age, they become independent. Young gray foxes breed at ten months of age. Gray foxes in the wild seldom live more than 6 years, although captives may survive to 14-15 years.
Predators
The gray fox has few natural predators. Bobcats, coyotes, great horned owls, and golden eagles may occasionally prey upon young gray foxes.
Social Behavior
- Social system - The gray fox is monogamous, possible maintaining permanent pair bonds although adults are solitary except when breeding and caring for young. Habitat structure and available food are important determinants or home range size and shape. Home range size varies from 75-653 ha (188-1633 acre). Densities are 1.2-2.1 gray foxes per square kilometer (247 acre).
- Communication - The gray fox uses vocal, chemical, tactile, and visual signals in social encounters. During the breeding season, individuals give sharp “barks” or “yips.” Chuckles, growls, and squeals are other vocalizations. A musk gland, the largest among North American canids, extends along approximately one half the upper surface of the tail. Products from this gland probably play a role in individual recognition. Gray foxes mark their home ranges with urine and feces which advertise ownership and sexual status. In some social contexts, gray foxes groom each other. Ritualized motor patterns and postures occur in aggressive, submissive, threat, and sexual contexts.
Additional References
Fritzell and K. J. Haroldson. 1982. Urocyon cinereoargenteus. Mammalian Species, 189:1-8
Seagears, C. B. 1944. The fox in New York. New York State Conservation Department, Albany, NY 85pp