The gray fox is a small canine predator. Scientific genus name — Urocyon was given by the American naturalist Spencer Byrd. Urocyon cinereoargenteus is the main species, of the two existing, it lives on the American mainland.
Origin of the species and description
Urocyon means tailed dog. Gray fox — a mammal of the family Canidae from North, Central and northern South America. Its closest relative is found in the Channel Islands — Urocyon littoralis. These two species are very similar to each other, but island animals are much smaller in size, but very similar in appearance and habits.
These dogs appeared in North America during the Middle Pliocene, about 3,600,000 years ago. The first fossil remains were found in Arizona, Graham County. Fang analysis confirmed that the gray fox is a different genus from the common fox (Vulpes). Genetically, the gray fox is closer to two other ancient lines: Nyctereutes procyonoides — East Asian raccoon dog and Otocyon megalotis — African big-eared fox.
Video: Gray fox
Found remains in two caves in northern California confirmed the presence of this animal in the late Pleistocene era. It has been proven that gray foxes migrated to the northeastern United States after the Pleistocene, due to climatic changes, the so-called medieval warming. There are also divergences into different but related taxa of gray foxes in western and eastern parts of North America.
The foxes of the Channel Islands are believed to have descended from mainland gray foxes. In all likelihood, they got there by swimming or on some objects, perhaps they were brought by man, since these islands were never part of the mainland. They appeared there about 3 thousand years ago, from different, at least 3-4 founders on the maternal side. The gray fox genus is considered the most basal of living canids, along with the wolf (Canis) and the rest of the foxes (Vulpes). This division occurred in North America about 9,000,000 years ago, during the late Miocene period.
Appearance and features
The gray fox is similar in appearance to its red distant relatives, but its coat has a gray color. The second binomial name is cinereoargenteus, which translates as ash silver.
The size of the animal is about the size of a domestic cat, but the long fluffy tail makes it look somewhat larger than it really is. The gray fox has rather short legs, giving it a stocky appearance. The body with the head is approximately 76 to 112 cm, and the tail – from 35 to 45 cm. Hind legs 10-15 cm, height at the withers & # 8212; 35 cm, and weight 3.5-6 kg.
There are significant regional and individual differences in size. Gray foxes in the northern part of their range tend to be somewhat larger than those in the south. Males are usually 5-15% larger than females. It is believed that individuals from the northern regions of the range are more colorful than those from the southern territories.
Subspecies of the gray fox from the island territories — Urocyon littoralis is smaller than mainland ones. Their length is 50 cm, height is 14 cm at the withers, tail is 12-26 cm. These subspecies have fewer vertebrae on the tail. The largest is found on Catalina Island, and the smallest on Santa Cruz Island. This is the smallest fox in the USA.
The upper body looks gray, due to the fact that individual hairs are black, white, gray. The lower part of the neck and abdomen are white, and the transition is indicated by a reddish edging. The top of the tail is gray with a black stripe of coarse hairs, like a mane, running down to the end. Paws are white, gray with red spots.
The muzzle is gray above, blacker on the nose. The coat under the nose and on the sides of the muzzle is white, contrasting with the black whiskers. A black stripe extends from the eye to the side. The color of the iris varies, with adults being gray or greyish-brown, and some may be blue.
Difference between foxes:
- reds have a white tail end, grays – black;
- greys have a shorter muzzle than redheads;
- redheads have slit-like pupils, while grays have oval ones;
- greys do not have “black stockings” on paws like red foxes.
Where does the gray fox live?
These canids are widely distributed in forested, shrubby, and rocky areas found in temperate, semi-arid, and tropical regions of North America and in the northernmost highlands of South America. The gray fox is increasingly found near human dwellings, despite the fact that it is very shy.
The habitat of the animal extends from the southern edge of central and eastern Canada to the states of Oregon, Nevada, Utah and Colorado in the United States, in the south & # 8212; to northern Venezuela and Colombia. From west to east, it is found from the Pacific coast of the United States to the shores of the Atlantic. This species is not found in the northern Rocky Mountains of the United States or the Caribbean watersheds. For several decades, mammals have expanded their range to habitats and areas that were previously unoccupied or where they were destroyed earlier.
In the east of the North. America, these foxes live in deciduous, pine forests, where there are old fields and woodlands. In the west of the North, they are found in mixed forests and farmland, in thickets of dwarf oak (chaparral forest), along the banks of reservoirs in the bush. They have adapted to the semi-arid climate of the southwestern United States and northern Mexico, where there is plenty of shrubs.
There are six different subspecies of the gray fox in the six Channel Islands. They easily get used to humans, often domesticated, used for pest control.
What does the gray fox eat?
These omnivorous predators, the diet changes depending on the season and the availability of animal prey, insects and plant matter. They mainly feed on small mammals, including mice, shrews, and voles.
In some areas the Florida rabbit as well as the Californian rabbit are the most important food items. In other regions where there are no or fewer rabbits, the American hare forms the basis of the menu of this predator, especially in winter. Gray foxes also prey on birds such as hazel grouse, reptiles and amphibians. This species also consumes carrion, such as deer killed in winter. Insects such as grasshoppers, beetles, butterflies and moths, these invertebrates are part of the diet of foxes, especially in summer.
Gray foxes are the most omnivorous canids in the Americas, relying more than eastern coyotes or red foxes on plant material year-round, but especially in summer and fall. Fruits and berries (such as: common strawberries, apples and blueberries), nuts (including acorns and beechnuts) are a large part of the plant-based items on the menu.
In some areas of the western United States, gray foxes are mostly parts of insectivorous and herbivorous animals. The same can be said about the island subspecies.
Character and lifestyle features
These mammals are active during all seasons. Like other species of North American foxes, the gray brother leads an active life at night. These animals typically have a daytime resting area in a tree or densely vegetated area, allowing them to forage at dusk or at night. Predators may also hunt during the day, with activity levels usually dropping sharply at dawn.
Gray foxes are the only canids (other than Asiatic raccoon dogs) that can climb trees with ease.
Unlike red foxes, gray foxes — agile climbers, although not as skilled as raccoons or cats. Gray foxes climb trees to forage, rest and escape from predators. Their ability to climb trees depends on their sharp, curved claws and the ability to rotate their front paws more than other canids. This gives them good grip when climbing tree trunks. The gray fox can climb inclined trunks and jump from branch to branch to a height of up to 18 meters. An animal descends along the trunk, for example, like domestic cats, or jumping over branches.
A fox’s lair is made, depending on the habitat and the availability of a food base. It is common for these animals to mark their homes with urine and feces to demonstrate their status in the area. Hiding its prey, the predator puts marks. Mammals make shelters in hollow trees, stumps or burrows. Such lairs can be located nine meters above the ground.
Some researchers note that these foxes are secretive and very shy. Others, on the contrary, say that animals show tolerance for humans and come quite close to housing, changing their behavior, adapting to the environment.
Grey foxes communicate with each other using various vocalizations, these are:
Most of the time adults make a hoarse bark, while youngsters — shrill screams, screams.
Social structure and reproduction
Gray foxes breed once a year. They are monogamous, like other North American foxes. For offspring, animals arrange shelters in hollow tree trunks or in the hollows of logs, also in windbreaks, shrubbery, rocky crevices, under stones. They can climb into abandoned dwellings or outbuildings, and also occupy abandoned burrows of marmots and other animals. They choose a place for a lair in clean wooded places, near water bodies.
Gray foxes mate from late winter to early spring. The time period varies depending on the geographic latitude of habitat and altitude. Breeding occurs earlier in the south and later in the north. In Michigan it may be early March, in Alabama mating peaks in February. There is no studied data on the duration of pregnancy, it is approximately equal to 53-63 days.
Cubs appear in late March or April, average litter size — four puppies, but can vary from one to seven, their weight is not more than 100 g. They are born blind, they see on the ninth day. They feed exclusively on mother’s milk for three weeks, then switch to mixed feeding. Completely stop sucking milk at six weeks. During the transition to another food, parents, most often the mother, bring the cubs another food.
At the age of three months, the young leave the den, starting to practice their skills in jumping and tracking, hunting with their mother. By four months, young foxes become independent. From the breeding season until the end of summer, parents with young children live as one family. In autumn, young foxes become almost adults. At this time, they have permanent teeth, and they can already hunt on their own. Families are falling apart. Young males become sexually mature. Maturity in females occurs after 10 months. Fertility of males lasts longer than that of females.
When the family breaks up, young males can retire in search of free territory for 80 km. Bitches are more inclined to the place where they were born and, as a rule, they do not go further than three kilometers.
Animals can use the lair at any time of the year for rest during the day, but more often, during childbirth and nursing offspring. Gray foxes live in the wild for six to eight years. The oldest recorded animal living in the wild was ten years old at the time of capture.
Natural enemies of gray foxes
This animal species has few enemies in the wild. Sometimes they are hunted by large eastern coyotes, red bobcats, virgin eagle owls, golden eagles, hawks. The ability of this animal to climb trees allows it to avoid meeting with other predators, which can be reached for lunch. This property also allows the gray fox to inhabit the same places as the eastern coyotes, sharing with them not only the territory, but also the food base. Predatory birds attacking from above represent a great danger. Lynxes mainly prey on babies.
The main enemy of this predator — human. Hunting and trapping of the animal is permitted in most of its range, and in many areas it is the main cause of death. In New York State, the gray fox — one of ten animal species that can be hunted for their fur. Hunting is permitted from October 25 to February 15 at any time of the day or night using firearms, bows or crossbows, but a hunting license is required. Gray fox hunters do not submit reports on the results, and therefore the number of animals killed is not taken into account in any way.
Disease is a less important factor in mortality than human exposure. Unlike the red fox, the gray fox has a natural resistance to sarcoptic mange (a debilitating skin disease). Rabies among this species is also rare. The main disease is canine distemper and canine parovirus. Of the parasites, trematodes are dangerous for the gray fox & # 8212; Metorchis conjunctus.
Population and species status
This species is stable throughout its range. Often foxes become casual victims of hunters, as their fur is not very valuable. Countries where the gray fox is found: Belize, Bolivar, Venezuela, Guatemala, Honduras, Canada, Colombia, Costa Rica, Mexico, Nicaragua, Panama, United States, El Salvador. This is the only species whose natural range covers part of North and part of South America. The population is distributed throughout the range with uneven density, there are areas with very high abundance, especially where ecological landscape conditions favor it.
Animals are universal in terms of their habitat. And they can live in different places, but they prefer forest areas more than steppes and other open spaces. The gray fox species is rated as Least Concern, and its range has increased over the past half century.
Due to the lack of reporting requirements for hunting results, it is difficult to estimate the number of gray foxes killed by hunters. However, 2018 New York state surveys of amateur game hunters showed a total of 3,667 gray foxes killed.
Among the island species, the population of three subspecies of the northern islands is declining. On the island of San Miguel, their number is a few individuals, and in 1993 there were several hundred (about 450). Golden eagles and animal diseases have played a large role in the decline in the population, but they do not fully explain the reasons for this decline in numbers. Breeding measures have been taken to save these species. On Santa Rosa Island, where in 1994 the number of foxes numbered more than 1,500, by 2000 it had dropped to 14.
On San Clement Island, just 200 km south of San Miguel, U.S. conservation authorities have almost eradicated another insular subspecies of the gray fox. This was done by accident, while fighting other predators that preyed on the endangered species of shrike. Fox numbers have fallen from 2,000 adults in 1994 to less than 135 in 2000
In many ways, the decline in the population is associated with golden eagles. The so-called golden eagle replaced the bald or bald eagle on the islands, the main food of which was fish. But it was destroyed earlier due to the use of DDT. The golden eagle first hunted wild pigs, and after their extermination, switched to gray foxes. Four subspecies of island foxes have been protected under US federal law as an endangered species since 2004.
These are island animals:
- Santa Cruz;
- Santa -Rosa;
- San Miguel;
- Santa Catalina.
Measures are now being taken to increase the population and restore the ecosystems of the Channel Islands. To track animals, radio collars are attached to them, which helps to determine the location of individuals. These efforts have brought some success.
The gray fox as a whole has a stable population and is not a cause for concern, it is worth taking care that the rarer subspecies of this animal are treated with care and anthropogenic impact would not lead to disaster .