Scientific name: Vulpes vulpes
Common name: Red fox
The red fox is found throughout the Northern Hemisphere in Europe, Asia and North America. It's range extends south into northern Africa and into the northern regions of India and Vietnam in Asia and Mexico on the North American continent. The red fox has been introduced into Australia and is now found throughout the Australian land mass.
The red fox is found in farmlands and brush lands, forests and suburban housing developments. In its wild ranges the red fox is very intolerant of human activity and intrusion but is capable in more settled areas of toning down this intolerance to a wary watchfulness. Red foxes live in dens dug into the soil. These burrows are usually very well concealed and are typically located within secluded regions of the individual's territory. Often a fox will have several dens within its territory and will quickly move to a new den site if disturbed at its currently inhabited burrow.
The red fox is nocturnal or, if the days are cloudy, possibly crepuscular. It is a carnivore but has a wide range of tolerated food types. Foxes will hunt and eat rabbits, mice, voles, birds, and insects but are less likely to eat shrews or moles. Foxes will eat any carrion or animal waste that they might encounter. They scavenge road kills, trash dumps, livestock offal piles and garbage cans. They also actively eat great quantities of earthworms and ,in season, fruits and berries (including blackberries and raspberries). Techniques that the foxes use to balance on their back legs while clipping off ripe blackberries from the thorny vines have been extensively described in the literature and are indicative of the great range of learned behaviors of which foxes are capable. Foxes have been reported to raid gardens (eating cabbages, potatoes etc) and farms (where they consume chickens and possibly lambs etc).
Studies have indicated that individual foxes may have distinct feeding preferences or "specialities" both in captivity and in the wild. A "bird eating" fox or a "mouse eating" fox will also take at need other types of food but will be most successful and focused on its very specific prey or other food type.
Reasons for the red fox's world wide distribution and continued survival even in the face of intense human predation are centered upon its broad acceptance of many types of habitats and its even broader tolerance of an astonishing range of food types.
The red fox is called the "cat-like" canine. Although quite obviously a member of the dog and wolf family of predators with overwhelming anatomical and behavior similarities to other canine species, the red fox's long, very thin canine teeth and its ventrally slit pupils with their well developed tapetum lucidum are extremely obvious cat-like features. These anatomical "cat-like" characteristics are accentuated by the fox's slinking, "mousing" hunting behaviors, and by its use of its sensitive front paws to capture and pin prey. Also, the red fox's sustained, piercing bite to effect a prey kill (as compared to the bite and shake killing method of most other canines) are remarkably cat-like in nature. The eye features unquestionally have evolved because of the nocturnal hunting behaviors of the fox. The teeth, use of paws to catch and pin prey and specific stalking behaviors are evolutionary strategies that are most efficient in the capture of small prey items like mice and voles. The "cat-like' nature of the red fox, then, is most logically due to the similarity of prey items and activity times that many cats and the red foxes share. One other cat-like behavior, though, that is not so easily explained is the lateral threat display used by foxes in aggressive displays (stand sideways, back arched, fur erect etc). This very classic "cat pose" seems out of place in the behavioral display of a canine.
The red fox is a very slenderly boned canine. Its limb bones in particular are much smaller in diameter relative to their length than any other canine species. Again, the predominance of small prey items taken by the fox reduces both the overall muscle mass requirements of the body and the need for a heavy, more protective skeletal system. A lighter although more fragile skeleton better fits the "needs" of the red fox by making locomotion much less energy demanding.
The red fox is between 35 and 40 inches long with one third of its length being its tail. The tails always have a white tip regardless of the overall color of the coat. Kits even at birth before mature hair color has been established have this white tail tip. The mature hair color is typically rust-red with ranges and also inter-mixed forms from black to a light gray "silver". The fox has long pointed ears and a long, thin muzzle. Weights vary through the year and with age, but average 6 to 7 kg for the male and 5 to 6 kg for the female. The long , bushy tail is a remarkable feature of the red fox. It would unquestionably be useful as a warm covering and wrap in the winter den and is also thought to facilitate balance and rapid turning during prey chases. Just why it has the white tip is a subject for much speculation.
Mating occurs in January to early March. Kits are born after a 51 to 53 day gestation (so in late February to mid-April). There can be between one to ten kits in a litter with an average between four and eight. The dog (the male) and the vixen (the female) tend to be monogamous both in the wild and in captivity and both are involved in the care and feeding of the young. Also, "helper foxes" (often females from the previous year's litter) have been observed assisting in the feeding and rearing of the new litter. Kits are weaned in six weeks and are fed on regurgitated food from the parents and the helper foxes.
Age structure analysis of red fox populations indicates that half of the kits in the litter are unlikely to live past one or two years of age. Predation, disease, parasites, accidents and starvation are common causes of death in these red foxes. An individual who does live to two years of age, though, has a very good chance of living another two or three years. The accumulated experience of the first two years of life make these "mature" foxes extremely efficient and successful survivors in their habitats. Small numbers of individuals up to eight or nine years of age are even found in wild populations, but the accumulation of debilitations from accident, injury or disease eventually overcomes even these most experienced foxes.
Foxes are very efficient predators and will kill large numbers of prey items (much more than they could possibly eat) if the food species or materials become available. Excess food is buried in caches. Caching behavior is a very strong instinctive drive in foxes and is displayed even in captivity and even in habitats in which burial of the food materials are not possible. Foxes also often play with their prey even after they are dead. Prey location employs all of the fox's senses. During daylight, vision is the most important prey locating sense. After dark olfaction is the most critical. The fox's very acute hearing is used in both day and night hunting. Any squeaking sound, in fact, will attract foxes often from considerable distances. Foxes have a very well developed sense of "three dimensional" hearing due to the placement and angling of their ears and the very slight time displacements of the arriving sound waves. The fox uses hearing almost exclusively in the winter as it hunts mice and voles moving about in the subivian space beneath the snow.
Foxes can hold up to one kilogram of flesh in their stomachs. They have short intestines (characteristic of most predators) through which the rapidly digested, nutrient rich food materials are quickly passed (food begins to show up in the feces within five to ten hours).
Foxes have abundant ectoparasites (including mites, fleas, ticks and lice). Several mite species cause mange ( a severe, inflammatory, hair loss condition). Many foxes observed in the wild are seen to be often heavily afflicted with mange. The debilitation of the protective winter coat, the blood loss and the compromised anti-infection barrier of the skin in a mangy fox is a contributing factor to the demise of many individuals. Foxes also have many internal parasites include nematodes (hookworm, trichinella, lung worms, heart worms (especially in regions in which domesticated dogs are infected), trematodes, and cestodes (including dog tapeworms and other species specific "fox" tapeworms).
Foxes are vulnerable to pesticide poisoning especially through biological magnification of pesticide residues in their food supply of rodents and birds. Foxes are also subject to a range of bacterial infections and poisoning (from wounds and from their carrion food sources). Viral diseases seen in foxes include distemper, encephalitis, hepatitis and rabies. Foxes can serve as a significant reservoir of the rabies virus (in Europe it is estimated that 85% of all rabies cases involved somewhere in the rabies chain, the red fox).
The fox has a rich history of representation in literature and myths. In the Bible (Ezekiel 13:4) the fox is used a symbol of lies and falsehood. In Pliny the fox is a rascal, in Aesop a sly, clever problem solver. Human reactions to the fox both over history and also in present times are varied but are seldom without passion. Even those who dislike this "cat-like" canine must, however, respect its tenacity and adaptability and its remarkable range of success and existence.