GrayFox Rando

Gray Fox

Urocyon cinereoargenteus
Chuck Fergus

Red and gray foxes are small, agile carnivores belonging to the same family (Canidae) as the dog, coyote and wolf. Both red and gray foxes are found throughout Pennsylvania. They are intelligent predators with extremely sharp senses of sight, smell and hearing (A fox can hear a mouse squeal at about 150 feet).

Biology

The gray fox (Urocyon cinereoargenteus) is 21 to 29 inches in length, plus an 11- to 16-inch tail, and weighs 7 to 13 pounds. Foxes look like they are heavier than these weights, an impression created by their full, thick fur. The gray fox has a grizzled gray coat, somewhat coarser than the red’s, with buff-colored under-fur. The gray’s tail is also long and bushy, with a black streak running down its length and a black tip. Foxes are swift runners and can swim if they have to. Both reds and grays are mainly nocturnal. The gray can climb trees —it is the only member of the canine family with this ability. Foxes are “opportunists” when it comes to feeding. This means they will eat whatever is most easily obtained. Foods include mice, rats, rabbits, woodchucks, opossums, porcupines, domestic cats, chickens, insects, squirrels, game birds, songbirds, bird eggs, fruits and grasses. Foxes are also scavengers, feeding on road-killed animals and winter kills. Diets of both reds and grays are essentially the same, but different food preferences, behavior patterns and preferred habitat often result in different types and amounts of food eaten. Both species cache uneaten food by burying it in loose earth. Males are called “dog” foxes and females “vixens.” In late winter, foxes can be heard barking at night, making their presence known to members of the opposite sex. Breeding usually takes place in February. Young are born following a 51-day gestation period for red foxes and a 63-day period for grays. Litters range from 4 to 10 young, with 6 the average. Young are born in dens. The red fox usually enlarges a woodchuck burrow or may den in a hollow log; the gray may also den beneath the ground or in crevices in rocky ledges. Underground dens for both species usually have several entrances. Fox pups weigh about eight ounces at birth, and their eyes are closed for the first 8 to 10 days. They are nursed by the female in the den for around a month. When the pups emerge, both mother and father keep them supplied with solid food until they are completely weaned after two or three months. They leave the den area in mid-July or August and may forage with their parents for another month until the family disbands. Foxes trapped in the fall are often young ones, on their own for the first time and establishing new territories. Both males and females are sexually mature at 10 months and may breed during their first winter. Grays often hole up for three or four days at a time during severe weather. Foxes may be afflicted with many parasites, including ticks, fleas, lice, mites, flukes and worms. Reds seem to be more susceptible to mange than gray foxes. Both species can contract rabies. Diseases and parasites strike foxes the hardest when they overpopulate an area; this is nature’s way of managing an excessive population. Wildlife researchers have live-trapped foxes, tagged and released them. These studies have shown that foxes, especially young adults, are susceptible to many limiting factors, including trapping, hunting, highway mortality and coyote predation. A life span of 10 to 12 years is possible, however.

Habitat

Red and gray foxes generally favor different types of habitat. The gray fox is more commonly found in brushy areas, swampy lands and rugged, mountainous terrain. But both species are very adaptable and can be found throughout the state, sometimes in areas not considered prime habitat. Red foxes seem less bothered by people than grays and often inhabit heavily populated areas, although they are rarely seen due to their nocturnal habits.  Grays are usually more aggressive than reds and where the ranges of the two overlap, the gray is typically the dominant species. But there are exceptions to every broad statement made about wildlife. Knowing that, you can figure somewhere out there are places where reds rule or where the two species coexist without problem.

Population

Fox populations are affected by availability of food, habitat suitability, coyote predation and hunting and trapping pressure. Pennsylvania studies have documented that some high-use agricultural areas — with little cover for either prey or predators — had only one fox per 300 acres, or 2.1 foxes per square mile. Wooded and less heavily farmed areas had one fox per 50 acres or 12.8 per square mile, a high concentration. Fox populations can be measured by different methods, including counting droppings on the snow, den reconnaissance and tracking studies. The gray fox has much larger toe pads and a smaller foot than the red, so the two can often be distinguished by their tracks.

URCI 01

PrintEmail

Pennsylvania Game Commission
Bureau of Wildlife Management
Attn: Mammal Atlas Coordinator
2001 Elmerton Avenue
Harrisburg, PA 17110
MammalAtlas@pa.gov
Pennsylvania Game Commission
Bureau of Wildlife Management
717-787-5529