Gray fox

The gray fox (Urocyon cinereoargenteus), or grey fox, is an omnivorous mammal of the family Canidae, widespread throughout North America and Central America. This species and its only congener, the diminutive island fox (Urocyon littoralis) of the California Channel Islands, are the only living members of the genus Urocyon, which is considered to be genetically sister to all other living canids.

It was once the most common fox in the eastern United States, and though still found there, human advancement and deforestation allowed the red fox to become the predominant fox-like canid. Despite this post-colonial competition, the gray fox has been able to thrive in urban and suburban environments, one of the best examples being southern Florida. The Pacific States and Great Lakes region still have the gray fox as their prevalent fox.

Etymology

The name of the gray fox's genus, Urocyon, comes from Ancient Greek words for "tail" and "dog." The species name cinereoargenteus combines words meaning "ashen" and "silver," which describes the color of the fox's tail. This name helps scientists and animal lovers identify and study this interesting creature.

Description

The gray fox is different from other similar animals because it has a mix of gray and black fur, a black stripe down its tail, and a strong neck. It also has a black tip on its tail. Unlike the red fox, the gray fox does not have black around its legs. It has white fur on its ears, throat, chest, belly, and hind legs, and black around its eyes, lips, and nose.

Gray foxes have longer, curved claws and can weigh between 3.6 to 7 kg, but some can be as heavy as 9 kg. They have a special kind of vision with oval-shaped pupils, unlike the slit-shaped pupils of red foxes. Their fur is shorter, making them look smaller than red foxes even though they can weigh about the same.

Origin and genetics

The gray fox first appeared in North America during the mid-Pliocene epoch, about 3.6 million years ago. Fossils have been found in Graham County, Arizona, alongside ancient animals like the giant sloth and early horses such as Nannippus and Equus.

Genetic studies show that the gray fox belongs to its own genus, Urocyon, which is closely related to all other living canids. It is also related to the raccoon dog of east Asia and the bat-eared fox of Africa. The gray fox has 66 chromosomes in its cells. Its smaller relative, the island fox, likely came from gray foxes that ancient humans carried to islands off the coast of California.

Distribution and habitat

The gray fox lives in many rocky, wooded, and brushy areas across the southern half of North America, from southern Canada (like Manitoba and southeastern Quebec) all the way down to parts of northern South America, including Venezuela and Colombia. It avoids the mountains in the northwestern United States. These foxes like places that mix woods with farms, such as juniper forests and ponderosa pine areas in the west, and deciduous forests in the east. They are the only fox species found in both North and South America. In some places, they are often seen near areas with lots of bushes and bluffs, and in southeastern Mexico, they like living close to human roads and settlements.

Behavior

The gray fox is very good at climbing trees. It has strong, hooked claws that help it climb tall trees to escape predators like the domestic dog or the coyote. It can climb up to 18 metres (59 feet) and jump between branches. During the day, it rests in hollow trees, stumps, or burrows, sometimes as high as 30 feet off the ground.

Before many people lived in North America, gray foxes lived mainly in forests with many deciduous trees. Today, gray foxes often live near places where humans are active, like areas with hardwood trees or roads. They prefer the edges of forests for moving around and hunting, and these areas also help them escape from larger predators like bobcats.

Interspecies competition

Gray foxes often hunt for the same prey as bobcats and coyotes in the same regions. To avoid competition, gray foxes have developed behaviors such as staying within their own hunting ranges and choosing different habitats. For example, in California, they live in chaparral where there are fewer competitors and the landscape helps them escape danger.

Even with these strategies, gray foxes are sometimes killed by bobcats and coyotes. These larger predators often leave the gray fox carcasses uneaten, showing that the gray foxes are victims of predation rather than food. Gray foxes are considered mesopredators, meaning they are mid-level predators, while coyotes act as apex predators in areas where larger predators like wolves are absent. This difference in their positions on the food chain influences how gray foxes behave around coyotes.

Reproduction

The gray fox is thought to be monogamous, like other foxes. Its breeding season changes depending on where it lives; in Michigan, it mates in early March, while in Alabama, breeding peaks in February. After a gestation period of about 53 days, a litter of one to seven kits is born, with an average of about four kits per female.

Kits become sexually mature around ten months old and start hunting with their parents at three months. By four months, they have their full set of teeth and can forage on their own. The family stays together until autumn, when the young males leave to find new territories, while females usually stay close to their birth den. Adult gray foxes typically live between six and ten years. They use logs, trees, rocks, burrows, or even old buildings as dens, especially during the time they have their kits.

Diet

The gray fox is an omnivorous hunter, meaning it eats both plants and animals. At night, it hunts alone and looks for food such as eastern cottontails, voles, shrews, birds, rodents like deer mice and woodrats, and sometimes jackrabbits. Gray foxes also eat fruits, nuts, and insects like grasshoppers and beetles, especially in the spring. When they find extra food, they may cache it, hiding it in a spot they can remember later.

Ecosystem role

Gray foxes help control the numbers of small rodents like woodrats, cotton rats, and mice, which are a big part of their diet.

Gray foxes can also carry parasites such as fleas, lice, nematodes, and tapeworms. In the United States, one common parasite is the flea Pulex simulans). Scientists have found new types of parasites in Mexico, and a warming climate might cause these parasites to move northward to new areas.

Hunting

Gray foxes are hunted in the U.S., especially when their fur is valuable. During the 1970s, the price of their pelts went up a lot, and the number of foxes hunted grew quickly. Today, it is reported that over 500,000 gray foxes are killed each year for their fur.

Main article: [Pelts]

Subspecies

The gray fox has 16 recognized subspecies. These subspecies live in different parts of North and Central America, such as New England, southern California, the eastern United States, Costa Rica, and many other regions. Each subspecies has a unique name that reflects where it is found.

Parasites

Gray foxes can carry several types of parasites. One common parasite is a type of worm called Metorchis conjunctus. In Texas, scientists found gray foxes with various tapeworms, such as Mesocestoides litteratus and Taenia pisiformis, as well as roundworms like Ancylostoma caninum. The tapeworm Taenia pisiformis was found most often and could affect the fox's health.