Red Fox Temporal range: Mid-Pleistocene–Recent
European red fox (V. v. crucigera), British Wildlife Centre, Surrey
Conservation status
Least Concern (IUCN 3.1)[1]
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Family:	Canidae
Tribe:	Vulpini
Genus:	Vulpes
Species:	V. vulpes
Binomial name
Vulpes vulpes (Linnaeus, 1758)
Subspecies
45 ssp., see text
Distribution of the red fox (orange).

The red fox (Vulpes vulpes) is the largest of the true foxes and the most geographically spread member of the Carnivora, being distributed across the entire northern hemisphere from the Arctic Circle to North Africa, Central America and Asia. Its range has increased alongside human expansion, having been introduced to Australia, where it is considered harmful to native mammal and bird populations. Because of these factors, it is listed as Least Concern for extinction by the IUCN.^[1] It is included among the IUCN's list of the "world's 100 worst invasive species".^[2]

The red fox originated from smaller-sized ancestors from Eurasia during the Middle Villafranchian period,^[3] and colonised North America shortly after the Wisconsian glaciation.^[4] Among the true foxes, the red fox represents a more progressive form in the direction of carnivory.^[5] Apart from its large size, the red fox is distinguished from other fox species by its ability to adapt quickly to new environments and, unlike most of its cousins, is not listed as Endangered anywhere. Despite its name, the species often produces individuals with abnormal colourings, including albinos and melanists.^[6] Forty-five subspecies are currently recognised,^[7] which are divided into two categories: the large northern foxes, and the small, primitive southern foxes of Asia and the Middle East.^[8]

Red foxes are social animals, whose groups are led by a mated pair which monopolises breeding. Subordinates within a group are typically the young of the mated pair, who remain with their parents to assist in caring for new kits.^[9] The species primarily feeds on small rodents, though it may also target leporids, game birds, reptiles, invertebrates^[10] and young ungulates.^[11] Fruit and vegetable matter is also eaten on occasion.^[12] Although the red fox tends to displace or even kill its smaller cousins, it is nonetheless vulnerable to attack from larger predators such as wolves, coyotes, golden jackals and medium and large-sized felines.^[13]

The species has a long history of association with humans, having been extensively hunted as a pest and furbearer for centuries, as well as being prominently represented in human folklore and mythology. Because of its widespread distribution and large population, the red fox is one of the most important furbearing animals harvested for the fur trade.^[14]

Evolution[link]

Comparative illustration of skulls of red fox (left) and Rüppell's fox (right). Note the more developed facial area of the former

The red fox is considered a more specialised, progressive form of Vulpes than the Afghan, corsac and Bengal fox in the direction of size and adaptation to carnivory ; the skull displays much fewer neotenous traits than in other species, and its facial area is more developed.^[5] It is, however, not as maximally adapted for a carnivorous diet as the Tibetan fox is.^[15]

Origins[link]

The species is Eurasian in origin, and may have evolved from either Vulpes alopecoides or the related Chinese V. chikushanensis, both of which lived during the Middle Villafranchian.^[3] The earliest fossil specimens of Vulpes vulpes were uncovered in Barany, Hungary dating from between 3.4—1.8 million years ago.^[16] The ancestral species was likely smaller than the current one, as the earliest red fox fossils are smaller than modern populations.^[3] The earliest fossil remains of the modern species date back to the mid-Pleistocene in association with the refuse of early human settlements. This has led to the theory that the red fox was exploited by primitive humans as both a source of food and pelts.^[17]

Colonisation of North America[link]

Red foxes colonized the North American continent, in two waves: during or before the Illinoian glaciation, and during the Wisconsinan glaciation.^[18] In the far north, red fox fossils have been found in Sangamonian deposits in the Fairbanks District and Medicine Hat. Fossils dating from the Wisconsian are present in 25 sites in Arkansas, California, Colorado, Idaho, Missouri, New Mexico, Tennessee, Texas, Virginia and Wyoming. Although they ranged far south during the Wisconsian, the onset of warm conditions shrank their range toward the north, and have only recently reclaimed their former American ranges thanks to human induced environmental changes.^[4] Genetic testing indicates that there are two distinct red fox refugiums in North America, which have been separated since the Wisconsian. The northern (or boreal) refugium occurs in Alaska and western Canada, and consists of the large subspecies alascensis, abietorum, regalis and rubricosa. The southern (or montane) refugium occurs in the Rocky Mountain's subalpine parklands and alpine meadows, the Cascade Range and Sierra Nevada. It encompasses the subspecies macroura, cascadensis and necator. The latter clade has been separated from all other red fox populations since the last glacial maximum, and may possess unique ecological or physiological adaptations.^[18]

Subspecies[link]

As of 2005^[update],^[7] 45 subspecies are recognised. In 2010, another possible distinct subspecies was discovered in Sacramento Valley through mitochondrial haplotype studies.^[19]

Substantial gene pool mixing between different subspecies is known; British red foxes have crossbred extensively with foxes imported from Germany, France, Belgium, Sardinia, and possibly Siberia and Scandinavia.^[20] European foxes were introduced to portions of the USA in the 18th century, thus crossbreeding with local North American populations.^[21] Also, introduced eastern red foxes in California may be interbreeding with local V. vulpes necator populations.^[22] Red fox subspecies are divided into two categories:^[8]

• Northern foxes: Large, brightly coloured foxes.
• Southern grey desert foxes: Includes the Asian subspecies griffithi, pusilla and flavescens. These foxes display transitional features between northern red foxes and smaller fox species ; their skulls possess more primitive, neotenous traits than the northern forms^[15] and are also much smaller ; the maximum sizes attained by southern foxes are invariably less than the average sizes of northern foxes. Their limbs are also longer, and their ears larger.^[23]

Red foxes living in Middle Asia show physical traits intermediate to the northern and southern forms.^[24]

Description[link]

Build[link]

Red fox (left) and corsac fox (right) yawning

Red foxes have elongated bodies and relatively short limbs. The tail, which is longer than half the body length^[52] (70% of head and body length^[53]), is long, fluffy and reaches the ground when in a standing position. Their pupils are oval and vertically oriented.^[52] Nictitating membranes are present, but move only when the eyes are closed. The forepaws have five digits, while the hind feet have only four and lack dewclaws.^[54] They are very agile, being capable of jumping over 2 metre high fences and swim well.^[55] Vixens have three pairs of teats,^[52] though vixens with 7, 9 or 10 teats are not uncommon.^[54] The testes of males are smaller than those of Arctic foxes.^[56]

Their skulls are fairly narrow and elongated with small braincases. Their canine teeth are relatively long. Sexual dimorphism of the skull is more pronounced than in corsac foxes, with female red foxes tending to have smaller than average skulls than males, with wider nasal regions and hard palates, as well as having larger canines.^[57] Their skulls are distinguished from those of dogs by their narrower muzzles, less crowded premolars, more slender canine teeth and their concave rather than convex profiles.^[58]

Dimensions[link]

Red foxes are the largest species of the genus Vulpes.^[59] However, relative to dimensions, red foxes are much lighter than similarly sized dogs of the Canis genus. Their limb bones, for example, weigh 30% less per unit area of bone than expected for similarly sized dogs.^[60] They display significant individual, sexual, age and geographical variation in size. On average, adults measure 35–50 cm (14–20 in) high at the shoulder and 45 to 90 cm (18 to 35 in) in body length with tails measuring 30 to 63 in (760 to 1,600 mm). The ears measure 7.7–12.5 cm (3–5 in) and the hind feet 12–18.5 cm (5–7 in). They weigh 2.2 to 14 kg (4.9 to 31 lb), with vixens typically weighing 15–20% less than males.^[61] Adult dog-foxes have skulls measuring 129–167 mm, while those of vixens measure 128–159 mm.^[5] The forefoot print measures 60 mm in length and 45 mm in width, while the hind foot print measures 55 mm long and 38 mm wide. They trot at a speed of 6–13 km/h, and have a maximum running speed of 50 km/h. They have a stride of 25–35 cm when walking at a normal pace.^[62] North American red foxes are generally lightly built, with comparatively long bodies for their mass and have a high degree of sexual dimorphism. British red foxes are heavily built, but short, while continental European red foxes are closer to the general average among red fox populations.^[63] The largest red fox on record in Great Britain was a 17.2 kg (38.1 lbs), 1.4m long male, killed in Aberdeenshire, Scotland in early 2012.^[64]

Fur[link]

The winter fur is dense, soft, silky and relatively long. In northern foxes, the fur is very long, dense and fluffy, but is shorter, sparser and coarser in southern forms.^[52] Among northern foxes, the North American varieties generally have the silkiest guard hairs,^[65] while most Eurasian red foxes have coarser fur.^[66] There are three main colour morphs; red, silver/black and cross (see Mutations).^[53] In the typical red morph, their coats are generally bright reddish-rusty with yellowish tints. A stripe of weak, diffuse patterns of many brown-reddish-chestnut hairs occurs along the spine. Two additional stripes pass down the shoulder blades which, together with the spinal stripe, form a cross. The lower back is often a mottled silvery colour. The flanks are lighter coloured than the back, while the chin, lower lips, throat and front of the chest are white. The remaining lower surface of the body is dark, brown or reddish.^[52] During lactation, the belly fur of vixens may turn brick red.^[54] The upper parts of the limbs are rusty-reddish, while the paws are black. The frontal part of the face and upper neck is bright brownish-rusty red, while the upper lips are white. The backs of the ears are black or brownish-reddish, while the inner surface is whitish. The top of the tail is brownish-reddish, but lighter in colour than the back and flanks. The underside of the tail is pale grey with a straw coloured tint. A black spot, the location of the supracaudal gland, is usually present at the base of the tail. The tip of the tail is white.^[52]

Mutations[link]

Various red fox colour mutations

White morph red foxes may be distinguished from Arctic foxes by their 25% greater size, longer muzzles, and longer, pointed ears ^[67] This example shows the dark pigment of the eyes, nose, and lips that would not occur in an albino. Complete albinism in red foxes is rare and primarily occurs in southern forest zones. Typically, albinism is accompanied by deformations and usually develops in years of insufficient food.^[68]

Atypical colourations in red foxes usually represent stages toward full melanism,^[6] and mostly occur in cold regions.^[69]

Colour variant	Image	Description
Red		The typical colouration. See Fur
Grey		The rump and spine is brown or grey with light yellowish bands on the guard hairs. The cross on the shoulders is brown, rusty brown or brownish-reddish. The limbs are brown[6]
Cross		The fur has a darker colouration to the former. The rump and lower back are dark brown or dark grey, with varying degrees of silver on the guard hairs. The cross on the shoulders is black or brown, sometimes with light silvery fur. The feet and head are brown[6]
Blackish-brown		The melanistic form of the Eurasian red fox. Has blackish-brown or black skin with a light-brownish tint. The skin usually has an admixture of various amounts of silver. Reddish hairs are either completely absent or in small quantities[70]
Silver		The melanistic form of the North American red fox, but introduced to the Old World by the fur trade. Characterised by pure black colour with a variable admixture of silver (covering 25–100% of the skin area)[70]
Platinum		Distinguished from the silver morph by its late pale, almost silver-white fur with a bluish cast[71]
Amber
Samson		Distinguished by its woolly pelt which lacks guard hairs[67][72]

Senses[link]

Red foxes have binocular vision,^[54] but their sight reacts mainly to movement. Their auditory perception is acute, being able to hear black grouses changing roosts at 600 paces, the flight of crows at 1/4-1/2 km and the squeaking of mice at about 100 metres.^[73] They are capable of locating sounds to within one degree at 700–3,000 Hz, though less accurately at higher frequencies.^[55] Their sense of smell is good, but weaker than that of specialized dogs.^[73]

Scent glands[link]

Red foxes have a pair of anal sacs lined by sebaceous glands, both of which open through a single duct. The anal sacs act as fermentation chambers in which aerobic and anaerobic bacteria convert sebum into odorous compounds, including aliphatic acids. The oval-shaped caudal gland is 25 mm long and 13 mm wide, and reportedly smells of violets.^[54][74] The presence of foot glands is equivocal. The interdigital cavities are deep, with a reddish tinge and smell strongly. Sebaceous glands are present on the angle of the jaw and mandible.^[54]

Behaviour[link]

A pair of European red foxes at the British Wildlife Centre, Surrey, England

Social and territorial behaviour[link]

Red foxes either establish stable home ranges within particular areas or are itinerant with no fixed abode.^[75] They use their urine to mark their territories. Urine is also used to mark empty cache sites, as reminders not to waste time investigating them.^[76] Red foxes live in family groups sharing a joint territory. In favourable habitats and/or areas with low hunting pressure, subordinate foxes may be present in a range. Subordinate foxes may number 1-2, sometimes up to 8 in one territory. These subordinates could be formerly dominant animals, but are mostly young from the previous year, who act as helpers in rearing the breeding vixen's kits. Alternatively, their presence has been explained as being in response to temporary surpluses of food unrelated to assisting reproductive success. Non-breeding vixens will guard, play, groom, provision and retrieve kits,^[9] an example of kin selection. Red foxes may leave their families once they reach adulthood if the chances of winning a territory of their own are high. If not, they will stay with their parents, at the cost of postponing their own reproduction.^[77]

European red fox kit, still in dark, woolly neonatal fur

Reproduction and development[link]

A pair of Cascade mountain foxes (V. v. cascadensis) mating in Washington D.C.

Red foxes reproduce once a year in spring. Two months prior to oestrus (typically December), the reproductive organs of vixens change shape and size. By the time they enter their oestrus period, their uterine horns double in size, and their ovaries grow 1.5-2 times larger. Sperm formation in males begins in August–September, with the testicles attaining their greatest weight in December–February.^[78] The vixen's oestrus period lasts 3 weeks,^[79] during which the dog-foxes mate with the vixens for several days, often in burrows. Copulation is accompanied by a copulatory tie which may last for more than an hour. The gestation period lasts 49–58 days.^[80] Though foxes are largely monogamous, DNA evidence from one population indicated large levels of polygyny, incest and mixed paternity litters.^[79] Subordinate vixens may become pregnant, but usually fail to whelp, or have their kits killed postpartum by either the dominant female or other subordinates.^[81]

The average litter size consists of four to six kits, though litters of up to 13 kits have occurred.^[80] Large litters are typical in areas where fox mortality is high.^[82] Kits are born blind, deaf and toothless, with dark brown fluffy fur. At birth, they weigh 56–110 g and measure 14.5 cm in body length and 7.5 cm in tail length. At birth, they are short-legged, large-headed and have broad chests.^[83] Mothers remain with the kits for 2–3 weeks, as they are unable to thermoregulate. During this period, the fathers or barren vixens feed the mothers.^[81] Vixens are very protective of their kits, and have been known to even fight off terriers in their defence.^[84] If the mother dies before the kits are independent, the father takes over as their provider.^[85] The kit's eyes open after 13–15 days, during which time their ear canals open and their upper teeth erupt, with the lower teeth emerging 3–4 days later.^[83] Their eyes are initially blue, but change to amber at 4–5 weeks. Coat colour begins to change at 3 weeks of age, when the black eye streak appears. By one month, red and white patches are apparent on their faces. During this time, their ears erect and their muzzles elongate.^[81] Kits begin to leave their dens and experiment with solid food brought by their parents at the age of 3–4 weeks. The lactation period lasts 6–7 weeks.^[78] Their woolly coats begin to be coated by shiny guard hairs after 8 weeks.^[81] By the age of 3–4 months, the kits are long-legged, narrow-chested and sinewy. They reach adult proportions at the age of 6–7 months.^[83] Some vixens may reach sexual maturity at the age of 9–10 months, thus bearing their first litters at one year of age.^[78] In captivity, their longevity can be as long as 14 years, though in the wild they typically do not survive past 1.5 years of age.^[86]

Denning behaviour[link]

Outside the breeding season, most red foxes favour living in the open, in densely vegetated areas, though they may enter burrows to escape bad weather.^[9] Their burrows are often dug on hill or mountain slopes, ravines, bluffs, steep banks of water bodies, ditches, depressions, gutters, in rock clefts and neglected human environments. Red foxes prefer to dig their burrows on well drained soils. Dens built among tree roots can last for decades, while those dug on the steppes last only several years.^[87] They may permanently abandon their dens during mange outbreaks, possibly as a defence mechanism against the spread of disease.^[9] In the Eurasian desert regions, foxes may use the burrows of wolves, porcupines and other large mammals, as well as those dug by gerbil colonies. Compared to burrows constructed by Arctic foxes, badgers, marmots and corsac foxes, red fox dens are not overly complex. Red fox burrows are divided into a den and temporary burrows, which consist only of a small passage or cave for concealment. The main entrance of the burrow leads downwards (40–45°) and broadens into a den, from which numerous side tunnels branch. Burrow depth ranges from 0.5–2.5 metres, rarely extending to ground water. The main passage can reach 17 metres in length, standing an average of 5–7 metres. In spring, red foxes clear their dens of excess soil through rapid movements, first with the forepaws then with kicking motions with their hind legs, throwing the discarded soil over 2 metres from the burrow. When kits are born, the discarded debris is trampled, thus forming a spot where the kits can play and receive food.^[87] They may share their dens with woodchucks^[88] or badgers.^[89] Unlike badgers, which fastidiously clean their earths and defecate in latrines, red foxes habitually leave pieces of prey around their dens.^[90] The average sleep time of a captive red fox is said to be 9.8 hours per day.^[91]

Communication[link]

Body language[link]

A European red fox (V. vulpes crucigera) in an inquisitive posture

Red fox body language consists of movements of the ears, tail and postures, with their body markings emphasising certain gestures. Postures can be divided into aggressive/dominant and fearful/submissive categories. Some postures may blend the two together.^[77]

A pair of Wasatch mountain foxes (V. v. macroura) squabbling

Inquisitive foxes will rotate and flick their ears whilst sniffing. Playful individuals will perk their ears and rise on their hind legs. Male foxes courting females, or after successfully evicting intruders, will turn their ears outwardly, and raise their tails in a horizontal position, with the tips raised upward. When afraid, red foxes grin in submission, arching their backs, curving their bodies, crouching their legs and lashing their tails back and forth with their ears pointing backwards and pressed against their skulls. When merely expressing submission to a dominant animal, the posture is similar, but without arching the back or curving the body. Submissive foxes will approach dominant animals in a low posture, so that their muzzles reach up in greeting. When two evenly matched foxes confront each other over food, they approach each other sideways and push against each other's flanks, betraying a mixture of fear and aggression through lashing tails and arched backs without crouching and pulling their ears back without flattening them against their skulls. When launching an assertive attack, red foxes approach directly rather than sideways, with their tails aloft and their ears rotated sideways.^[77] During such fights, red foxes will stand on each other's upper bodies with their forelegs, using open mouthed threats. Such fights typically only occur among juveniles or adults of the same sex.^[92]

Vocalisations[link]

Red fox crying and gekkering

Red foxes have a wide vocal range, and produce different sounds spanning five octaves, which grade into each other.^[93] Recent analyses identify 12 different sounds produced by adults and 8 by kits.^[92] The majority of sounds can be divided into "contact" and "interaction" calls. The former vary according to the distance between individuals, while the latter vary according to the level of aggression.^[93]

• Contact calls: The most commonly heard contact call is a 3–5 syllable barking "wow wow wow" sound, which is often made by two foxes approaching one another. This call is most frequently heard from December to February (when they can be confused with the territorial calls of tawny owls). The "wow wow wow" call varies according to individual; captive foxes have been recorded to answer pre-recorded calls of their pen-mates, but not those of strangers. Kits begin emitting the "wow wow wow" call at the age of 19 days, when craving attention. When red foxes draw close together, they emit trisyllabic greeting warbles similar to the clucking of chickens. Adults greet their kits with gruff huffing noises.^[93]

• Interaction calls: When greeting one another, red foxes emit high pitched whines, particularly submissive animals. A submissive fox approached by a dominant animal will emit an ululating siren-like shriek. During aggressive encounters with conspecifics, they emit a throaty rattling sound, similar to a ratchet, called "gekkering". Gekkering occurs mostly during the courting season from rival males or vixens rejecting advances.^[93]

Another call which does not fit into the two categories is a long, drawn out, monosyllabic "waaaaah" sound. As it is commonly heard during the breeding season, it is thought to be emitted by vixens summoning males. When danger is detected, foxes emit a monosyllabic bark. At close quarters, it is a muffled cough, while at long distances it is sharper. Kits make warbling whimpers when nursing, these calls being especially loud when they are dissatisfied.^[93]

Ecology[link]

Diet, hunting and feeding behaviour[link]

High Sierra fox (V. v. necator) with a squirrel carcass in the Coast range mountains of San Luis Obispo county, California

Red fox with rodent prey in Canada

Red foxes are omnivores with a highly varied diet. In the former Soviet Union, up to 300 animal and a few dozen plant species are known to be consumed by them.^[10] They primarily feed on small, mouse-like rodents like voles, mice, ground squirrels, hamsters, gerbils,^[10] woodchucks, pocket gophers and deer mice.^[12] Secondary prey species include birds (with passeriformes, galliformes and waterfowl predominating), leporids, porcupines, raccoons, opossums, reptiles, insects, other invertebrates and flotsam (marine mammals, fish and echinoderms).^[10][12] On very rare occasions, they may attack young or small ungulates.^[11] They typically target mammals up to about 3.5 kg in weight, and require 500 grams of food daily.^[55] Red foxes readily eat plant material and in some areas, fruit can amount to 100% of their diet in autumn. Commonly consumed fruits include blueberries, blackberries, raspberries, cherries, persimmons, mulberries, apples, plums, grapes and acorns. Other plant material includes grasses, sedges and tubers.^[12]

Red foxes prefer to hunt in the early morning hours before sunrise and late evening.^[94] When hunting mouse-like prey, they first pinpoint their prey's location by sound, then leap, sailing high above their quarry, steering in mid-air with their tails, before landing on target up to five metres away.^[60] They typically only feed on carrion in the late evening hours and at night.^[95] They are extremely possessive of their food, and will defend their catches from even dominant animals.^[96] Red foxes may occasionally commit acts of surplus killing; during one breeding season, four foxes were recorded to have killed circa 200 black-headed gulls each, with peaks during dark, windy hours when flying conditions were unfavourable. Losses to poultry and penned game birds can be substantial because of this.^[79][97] Red foxes seem to dislike the taste of moles, but will nonetheless catch them alive and present them to their kits as playthings.^[98]

Enemies and competitors[link]

Golden eagle feeding on red fox, Navasrky, Czech Republic

Red foxes typically dominate other fox species. Arctic foxes generally escape competition from red foxes by living farther north, where food is too scarce to support the larger-bodied red species. Although the red species' northern limit is linked to the availability of food, the Arctic species' southern range is limited by the presence of the former. Red and Arctic foxes were both introduced to almost every island from the Aleutian Islands to the Alexander Archipelago during the 1830s–1930s by fur companies. The red foxes invariably displaced the Arctic foxes, with one male red fox having been reported to have killed off all resident Arctic foxes on a small island in 1866.^[99] Where they are sympatric, Arctic foxes may also escape competition by feeding on lemmings and flotsam, rather than voles, as favoured by red foxes. Both species will kill each others' kits, given the opportunity.^[100] Red foxes are serious competitors of corsac foxes, as they hunt the same prey all year. The red species is also stronger, is better adapted to hunting in snow deeper than 10 cm and is more effective in hunting and caching medium to large-sized rodents. Corsac foxes seem to only outcompete red foxes in semi-desert and steppe areas.^[101] In Israel, Blanford's foxes escape competition with red foxes by restricting themselves to rocky cliffs and actively avoiding the open plains inhabited by red foxes.^[99] Red foxes dominate kit and swift foxes. Kit foxes usually avoid competition with their larger cousins by living in more arid environments, though red foxes have been increasing in ranges formerly occupied by kit foxes due to human induced environmental changes. Red foxes will kill both species, and compete for food and den sites.^[102] Grey foxes are exceptional, as they dominate red foxes wherever their ranges meet. Historically, interactions between the two species were rare, as grey foxes favoured heavily wooded or semiarid habitats as opposed to the open and mesic ones preferred by red foxes. However, interactions have become more frequent due to deforestation allowing red foxes to colonise grey fox inhabited areas.^[102]

Wolves may kill and eat red foxes in disputes over carcasses.^[103][104] In areas in North America where red fox and coyote populations are sympatric, fox ranges tend to be located outside of coyote territories. The principal cause of this separation is believed to be active avoidance of coyotes by the foxes. Interactions between the two species vary in nature, ranging from active antagonism, to indifference. The majority of aggressive encounters are initiated by coyotes, and there are few reports of red foxes acting aggressively toward coyotes except when attacked or when their kits were approached. Foxes and coyotes have sometimes been seen feeding together.^[105] In Israel, red foxes share their habitat with golden jackals. Where their ranges meet, the two canids compete due to near identical diets. Foxes ignore jackal scents or tracks in their territories, and avoid close physical proximity with jackals themselves. Studies show that in areas where jackals become very abundant, the population of foxes decreases significantly, apparently because of competitive exclusion.^[106]

Red foxes dominate raccoon dogs, sometimes killing their kits or biting adults to death. Cases are known of foxes killing raccoon dogs entering their dens. Both species compete for mouse-like prey. This competition reaches a peak during early spring, when food is scarce. In Tartaria, red fox predation accounted for 11.1% of deaths among 54 raccoon dogs, and amounted to 14.3% of 186 raccoon dog deaths in north-western Russia.^[107]

They may kill small mustelids like weasels,^[102] stone martens,^[108] pine martens, stoats, kolonoks, polecats and young sables. Eurasian badgers may live alongside red foxes in isolated sections of large burrows.^[89] It is possible that the two species tolerate each other out of commensalism ; foxes provide badgers with food scraps, while badgers maintain the shared burrow's cleanliness.^[90] However, cases are known of badgers driving vixens from their dens and destroying their litters without eating them. Wolverines may kill red foxes, often whilst the latter are sleeping or near carrion. Foxes in turn may kill, unattended young wolverines.^[89]