(Vulpes vulpes Desmarest)
From: Saunders, D. A. 1988. Adirondack Mammals. State University of New York, College of Environmental Science and Forestry. 216pp.
The red fox has a long, bushy tail, a narrow, pointed muzzle, and thick, soft fur. The tip of the tail, lower regions of the face and muzzle, throat, chest, and belly are white. The slender legs, feet, nose, and backs of the pointed, erect ears are black. The upper parts of the body, head, and tail except for the tip, are yellowish or reddish orange. Blackish, brownish, or grayish color phases occur but are uncommon. The eyes are yellowish with dark, elliptical pupils. The toes have blunt claws. Adults are approximately 92-107 cm (36-42 in) in total length, the tail accounting for slightly more than one-third of its length. Weight varies from 3.6-7.7 kg (8-17 lb) but most adults weigh 4.5-5.0 kg (10-11 lb). Males are heavier than females.
Range and Habitat: In North America, the red fox occurs throughout Canada, and most of the U.S., except for parts of the Southwest, the extreme Southeast, and the Great Plains. This species occupies all terrestrial habitats in the Adirondack Park, from the lowest to the highest elevations, but prefers meadows, agricultural lands, forest openings, brushy fields, and forest and woodland edges.
The red fox often rests or sleeps in thick cover on a prominence such as a wooded ridge or hilltop, but uses dens in wet weather and for raising young. Dens may be in hollow logs or rocky crevices. However most are in ground burrows that a red fox may dig, or in most cases, remodels after the previous owners, e.g., a woodchuck or striped skunk, have abandoned them. Fox dens tend to be on slopes, ridges, or knolls with good drainage and loose soils. Extensive alterations of pre-existing burrows may result in a system of tunnels 7.6-22.9 m (25-75 ft) in length, 0.9-1.2 m (3-4 ft) in depth, and with two or more entrances 20.3-38.1 cm (8-15 in) in diameter. Red fox dens usually have mounds of soil near the entrances and open areas closeby where the young socialize. Accumulations of parts of prey, feces, and urine are another characteristic of den sites.
Food and Feeding Behavior: The omnivorous red fox scavenges carrion, gleans fruits, berries, and seeds, and actively hunts animals. Raspberries, wild strawberries, beechnuts, acorns, corn, apples, and grapes are a few of the plant foods it eats. Birds and their eggs, the young of many wild mammals, woodchucks, muskrats, chipmunks, insects, turtles and their eggs constitute red fox prey. Mice, voles, eastern cottontails, and snowshoe hares are staples in the diet. The red fox hunts by coursing back and forth over an area, detecting prey by scent and sound. The fox may then rush and grab its quarry or creep close enough to pounce on its victim, trapping the animal. Family groups and pairs may sometimes hunt cooperatively, ambushing or surrounding prey. Each red fox requires 0.5 kg (1 lb) of food per 24 hour period, and this rather large quantity may explain why foxes cache prey, either storing it in their den or burying it in the ground. Surplus stores provide nutrition when prey is scarce.
Activity and Movement: The red fox is active during all seasons, and most of its activity takes place at night or at twilight, but occasionally during daylight. Foraging during the day is more frequent when adults are hunting food for their young. This species swims well, but most of its travel is on land along well-defined trails. The normal manner of locomotion is by walking or trotting, but for brief periods a red fox can run, attaining a speed of about 42 km/h (26 mph).
Reproduction: Red foxes breed from late December until the end of March, with most matings taking place in January and February. In March or April, occasionally later, a female bears her annual litter in a grass-lined chamber of the den. Litter size varies from 1-11, but averages 6. Newborn red foxes are blind, weigh about 96 g (3.4 oz), and are covered with fine-textured gray fur. By 9 days of age, the eyes begin to open. At 28-35 days, the young make their first trips to the den entrance where they play with each other, and with the remains of prey and other items the adults carry to the den entrance. (Often, the adults move the young to a nearby den, sometimes dividing the litter between 2 dens). The young are weaned by 12 weeks of age, and then accompany their parents on foraging trips. In late summer and early autumn, the litter disperses; the males leaving first and traveling farther. Both sexes are sexually mature at 10 months, although they may not breed until yearlings. The red fox has a potential life span of 15 years but few wild foxes survive more than 4 to 6 years.
Predators: Adult red foxes have few natural predators except for the coyote. Many carnivorous animals including larger birds of prey may kill the young. Diseases, rather than predators, or hunters and trappers who take this species for its pelt, appear to keep populations depressed. Although the red fox is a vector of rabies, canine distemper and, especially, sarcoptic mange are more important sources of mortality.
- Social system - Adults form pair bonds during the breeding season. Pairs may involve the same mates from previous years or new ones. Some males are polygamous (paired with more than one female simultaneously) although the frequency of this mating system is not known. Non-breeding yearling females may function as “helpers” by guarding and hunting prey for their parents’ young. Males exhibit parental care by bringing food to their mates and later by provisioning the young with food and in teaching them to hunt. The red fox has a home range, which for individuals, varies in size with such factors as the availability of food and den sites, and possibly with the density of the local fox population. Estimates of home range size from studies conducted throughout the range of this species vary from 57.5 ha to 768 ha (142-1920 acre). A pair may share a home range but avoid each other (solitary) except during the reproductive period. Home ranges of pairs usually do not overlap; a male may exclude other red foxes from a core area or “territory” around the natal den. In agricultural lands, the average density is 1.6 red foxes per 256 ha (640 acre).
- Communication - A musk gland, located on the upper surface and near the base of the tail, produces substances that aid in individual recognition. Anal and local glands are present. Urine and feces, deposited on the perimeter of the home range and near dens and trails function to advertise occupancy. Red foxes vocalize with yips, barks, screeches, and other shrill sounds that function in long distance communication, e.g., to maintain contact between mates. Ritualized postures and stereotyped motion patterns serve as signals between individuals in close proximity. Tail and ear positions play a key role in these visual signals.
Ables, E.D. 1974. Ecology of the red fox in North America. Pp. 148-163 in M.W. Fox, editor. The wild canids. Van Nostrand Reinhold Co., New York, 508pp.
Shelden, W.G. 1949. Reproductive behavior of foxes in New York State. Journal of Mammalogy, 30:236-246.
Storm, G.L., R.D. Andrews, R.L. Phillips, R.A. Bishop, D.B. Siniff, and J.R. Tester. 1976. Morphology, reproduction, dispersal and mortality of Midwestern red fox populations. Wildlife Monographs, 49:1-82.
Tullar, B.F., Jr. and L.T. Berchielli, Jr. 1982. Comparison of red foxes and gray foxes in central New York with respect to certain features of behavior, movement, and mortality. New York Fish and Game Journal, 29:127-133.