The red fox (Vulpes vulpes) is a member of the Order Carnivora and the dog family Canidae. Red foxes occupy the largest geographic range of any member of the Carnivora, across the entire Northern Hemisphere, Central America, and Asia. The European red fox is the same species as the American red fox. There are currently 45 recognized subspecies of Vulpes vulpes, and while the classic image of a red fox may be a medium-sized canine with orange-red fur on its head, back, and sides; white fur on its chest and neck; black legs and feet; pointed black ears; and a long, bushy tail tipped in white, the reality is that the 45 subspecies differ greatly in size and color. Only the white tip on the tail distinguishes the red fox from other fox species. In addition to the differences in physical appearance between subspecies, members of the same red fox subspecies may have different color morphs. The three most common color morphs are red, silver/black, and cross. Color variations are more common in colder regions than they are in the southern parts of the range.

Red foxes are one of only six mammal species that are native to Kodiak Island, and the Kodiak red fox is a separate, distinct subspecies (Vulpes vulpes harrimani). Members of this subspecies are very large with a huge tail, coarse, thick fur on the lower back and tail, and a thick ruff around the neck and shoulders, especially in the winter. Most Kodiak red foxes are either cross foxes with a black/brown cross on the back and shoulders, or they are red in coloration. Silver foxes make up a smaller percentage of the population and are striking with black fur and silver-tipped guard hairs.

The red fox is the largest member of the true foxes. It has a head and body length that measures approximately 22 – 32 inches (56-82 cm), relatively short limbs, and a fluffy tail that is approximately 14 – 16 inches (36-43 cm) long. Adults weigh between 6 and 15 lbs. (2.7-6.8 kg), but the size and weight vary depending on the subspecies. The front paws of a red fox have five digits while the back feet have only four. Red foxes are capable of jumping over a six ft. (2 m) high fence and they can run nearly 30 mph (48.28 km/h).

The red fox has extremely good hearing and unlike other mammals, can hear low-frequency sounds very well, allowing it to detect small animals digging underground so it can dig the prey out of the dirt or snow. Although not as acute as its hearing, the red fox has a good sense of smell and binocular vision that reacts mainly to movement.

Anal and supra-caudal glands, as well as glands around the lips, jaws, and on the pads of the feet, allow foxes to leave and detect scents that may mark a territory or a food cache. Foxes use urine to mark their territories and food caches. A male raises one hind leg and sprays urine in front of him, while a female squats and sprays urine between her hind legs.

Red foxes are considered solitary, and they do not form packs like wolves. They often do live in family groups, though, with a dominant male and female and often a few subordinate foxes all sharing the same home range. Subordinate females may help guard, feed and care for the kits.

In Alaska, voles appear to be the food of choice for foxes, but the red fox is an omnivore and will eat fruits, berries, vegetation, insects, birds, rabbits, squirrels, and other small mammals. On Kodiak, it is common to see foxes on the beach feeding on sea urchins and other invertebrates and digging for worms. Red foxes are considered nocturnal or crepuscular (active at dawn and dusk), but they may be active at any time of the day, and on Kodiak, they are often most visible on the beaches during the morning and evening low tides. When hunting a vole, a fox locates the vole by sound and then jumps in the air and lands on its target much like a cat does. An adult red fox will eat between one and two pounds (.5 to 1.0 kgs.) a day.