Foxes

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 North America. They are intelligent predators with extremely sharp senses of sight, smell and hearing (a fox can hear a mouse squeal at about 150 feet).

Gray Fox. Photo courtesy US Fish and Wildlife Service.

Foxes are swift runners and can swim if they have to. Both reds and grays are mainly nocturnal. The grays 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.

Resource: Wildlife Notes: Foxes By Chuck Fergus. Pennsylvania Game Commission - State Wildlife Management Agency

Red fox. Photo courtesy US Fish & Wildlife Service.

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.

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 10-12 years is possible, however.

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.

Movements in gray and red fox populations are basically of two types. The first is dispersal, or the movement of young in late summer or early fall. Dispersal spreads the population out, with each young fox moving several miles -- occasionally 50 miles or more -- to set up its own home territory. The second type of movement is displacement, which is caused by habitat changes and predation. There are also localized movements, the travels of individual within their home territory or range. From tracking studies, biologists estimate that a fox travels an average of five miles in search of food on a winter night.

Populations also fluctuate and shift, often as a result of human activities such as logging, farming, construction and hunting. Disease also plays a role. In areas where mange outbreaks occur, red fox populations are often severely impacted. But foxes are very resilient. Both species seem to readily rebound from disease and other limiting factors, so long as the area they inhabit can provide food, escape cover and safe havens.

Foxes are often blamed for decreasing game populations, but most of the time the number of game birds and animals taken by foxes and other predators is insignificant compared to other natural losses.
When all facts are considered, habitat change is most often found to be the main contributor to lower small game populations. It's true that foxes take grouse, pheasants, rabbits and other game, but these are usually "surplus" individuals, those animals that would likely die from other causes -- accidents, disease, starvation, etc. -- before the next breeding season.

Resource: Wildlife Notes: Foxes By Chuck Fergus. Pennsylvania Game Commission - State Wildlife Management Agency

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