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San Joaquin Kit Fox

Vulpes macrotis mutica

family of San Joaquin Kit Foxes


The largest subspecies of kit fox, the San Joaquin Kit Fox can reach a length of 32 inches, including the tail, a height of 12 inches at the shoulder, and a weight of 5 pounds.

Fur color is light buff to grayish along the back and tail; gray, rust, or yellowish along the sides; and whitis on the belly. The color tends to become darker in the summer and lighter in the winter. The backs of the ears and tip of the tail are black in both winter and summer.

Like other kit foxes, the San Joaquin has large ears set close together, a slender body, and long legs. Its most distinctive features are its hairy paw pads, which allow them to get better traction on sandy soil.

Distribution and Habitat

Believed to have once been fairly common throughout the San Joaquin Valley of California, the San Joaquin Kit Fox is now restricted to the eastern side of that valley, with the majority being found in just six counties. Human activity, including construction of subdivisions, roads, etc., continues to affect the San Joaquin's range, and the overall population is currently being broken into individual, relatively isolated, subpopulations.

distribution of the San Joaquin kit fox

The San Joquin Kit Fox prefers grasslands and scrublands, but will adapt to life on the fringes of populated areas if there are enough suitable denning locations.

Listed as endangered on both national and California lists, the total wild population of San Joaquin Kit Fox is believed to number less than 7,000 individuals.

Habits and Behaviors

Although it is primarily nocturnal, the San Joaquin Kit Fox may be seen during the day in the spring and early summer.

Like other kit foxes, the San Joaquin lives in a den. While a San Joaquin will excvate its own den (in loose soil), it will also take advantage of a burrow or den originally excavated by another animal. It will also take advantage of man-made sites such as irrigation pipes, drainage culverts, crawl spaces under buildings, etc. The fox will change dens frequently, with some individuals known to change dens as often as every 2 or 3 days. Whether built from scratch or adapted from a pre-existing den, each den is itself quite complex, with multiple chambers and entrances.

While a mating pair may stay together year round, the individuals will not typically share a den.

Individual kit fox ranges vary in size depending on availability of food, but the average is 1 or 2 square miles.


San Joaquin Kit Foxes mate from December into March. The mother gives birth to 3-5 pups in a specially-built den. The pups remain in the den until being weaned at one month, during which time the male brings food to the female. Although they can hunt for themselves at 4-5 months, the pups may stay with their birth parents through raising of the next litter. Sexual maturity is reached at about 22 months, and the average maximum lifespan in the wild is 7 years.


San Joaquin Kit Foxes prey on a variety of rodents, as well as squirrels, hares and rabbits, birds, lizards, and even insects; they will also eat grasses and other vegetation.

Scientific Classification

phylum Chordata
subphylum Vertebrata
class Mammalia
order Carnivora
family Canidae
genus & species Vulpes macrotis mutica

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The Robinson Library >> Family Canidae

This page was last updated on June 20, 2018.