The corsac fox (Vulpes corsac) is a mammal of the order Carnivora.
It occurs from the lower Volga river east across a wide area of central Asia, including Kazakhstan, Uzbekistan, Turkmenistan, Mongolia, Iran, Tajikistan, Kyrgyzstan, Afghanistan, China and Russia.
The corsac fox is an inhabitant of steppes and semi-desert. It avoids areas used for agricultural purposes, forests, and thickets. It lives in adjoining burrows that were dug by other animals, then taken over by the fox.
The lifespan of corsac fox is up to 9 years in the wild and up to 12 years in captivity.
The corsac fox is a medium-sized fox, with a head and body length of 45 to 65 cm (18 to 26 in), and a tail 19 to 35 cm (7.5 to 13.8 in) long. Adults weigh from 1.6 to 3.2 kilograms (3.5 to 7.1 lb).
It has grey to yellowish fur over much of the body, with paler underparts and pale markings on the mouth, chin, and throat. During the winter, the coat becomes much thicker and silkier in texture, and is straw-grey in colour, with a darker line running down the back.
While it is reported to be nocturnal in the wild, in captivity it is very active during the day. This can be explained by increasing human disturbances, causing them to become active at night to avoid humans.
Their diets consist mainly of insects and small rodents, such as voles, gerbils, jerboas, hamsters, and ground squirrels. They may also eat larger prey from time to time, including hares and pikas, and will scavenge for carrion and human refuse. Although predominantly carnivorous, they do occasionally eat fruit and other vegetation, especially when animal prey are scarce.
Their senses of hearing, vision, and smell are excellent.
They are excellent climbers but run with only moderate speed and can be caught by a slow dog.
Corsac foxes are reported to be nomadic and do not keep a fixed home range, they will migrate south when hunting is difficult due to deep snow and ice.
This species is more social than other foxes. Some individuals even live together in the same burrow.
Males will initially fight for access to females, but eventually establish a monogamous bond, and assist in the raising of their young.
The time of mating for the corsac fox is between January and March with a gestation period of 50-60 days. Litter sizes are typically between 2 and 6 young at a time, but there are some reported cases of a litter of up to 11 young.
Since 2004, it has been classified as least concern by IUCN, but populations fluctuate significantly, and numbers can drop tenfold within a single year.
Natural predators of corsac foxes include wolves, eagles, buzzards, and eagle-owls.
The major threat posed to the corsac fox is poaching.
They are slow runners and are easily caught by hunters, and their population has been reduced in areas where they have been heavily hunted for their fur. In the late 19th century, up to 10,000 foxes were killed annually for pelt trade.
Fossils of corsac foxes date back to the mid-Pleistocene, and show the species once reached as far west as Switzerland, and as far south as Crimea.
The word “corsac” is derived from the Russian name for the animal, “korsák” (корса́к), derived ultimately from Turkic “karsak”.