The Kit Fox inhabits arid and semi-arid regions encompassing desert scrub, chaparral, halophytic, and grassland communities (McGrew 1979, O'Farrell 1987). Areas with sparse ground cover are preferred (McGrew 1977, Cypher et al. 2013). It is found in elevations ranging from 400–1,900 m a.s.l., although Kit Foxes generally avoid rugged terrain with slopes >5% (Warrick and Cypher 1998). Loose textured soils may be preferred for denning. Kit Foxes will use agricultural lands, particularly orchards, on a limited basis, and also can inhabit urban environments (Morrell 1972, Cypher 2010). Home range size varies from 251 ha to 1160 ha and generally does not differ between sexes (Cypher 2003). Size can vary with habitat conditions, particularly food availability (Spiegel 1996, Zoellick et al. 2002). Kit foxes are primarily nocturnal and nightly movements exceeding 14 km have been reported (Zoellick et al. 1989, 2002). Kit Foxes use dens year-round and uses include daytime resting, escaping predators, avoiding temperature extremes, conserving moisture, and bearing and rearing young (Egoscue 1962, Morrell 1972, Koopman et al. 1998). Kit Foxes can excavate their own dens, but also will modify and use the burrows of badgers, ground squirrels, prairie dogs, and kangaroo rats (Morrell 1972, List 1997, Koopman et al. 1998). Dens are distributed throughout home ranges, and an individual fox typically uses over 11 dens during a given year (Koopman et al. 1998).

Kit Foxes primarily consume animal prey and common items include rodents, rabbits, invertebrates, birds, lizards, and snakes. Among rodents, kangaroo rats, pocket mice, prairie dogs, and ground squirrels generally are preferred, and common invertebrate prey include beetles, crickets, and grasshoppers (Cypher 2003, List et al. 2003). Fluctuations in food availability related to variable annual precipitation levels are a primary factor driving Kit Fox population dynamics (White and Garrott 1997, Cypher et al. 2000). Kit Foxes do not require free water but will drink it if available (Egoscue 1956, Golightly and Ohmart 1984).

Kit Foxes experience intense interference and exploitative competition from other species, particularly coyotes (White et al. 1995, Cypher and Spencer 1998, Kozlowski et al. 2008). Other competitors include bobcats, badgers, golden eagles, and red foxes. Predators generally are the primary source of mortality, but other causes include vehicles, harvest, and rodenticides (Ralls and White 1995; Cypher et al. 2000, 2014). Disease does not appear to be a significant factor in most Kit Fox populations. At one site, annual survival probabilities for adults ranged from 0.20 to 0.81 over 16 years with a mean of 0.44 (Cypher et al. 2000). 

Kit Foxes pair during October and November (if not already paired), and breed in December and January (Egoscue 1956). Gestation is 49-55 days, and parturition occurs during January-March (Egoscue 1956, Egoscue 1962, Zoellick et al. 1987). Typical litter size averages about 4 and ranges from 1-9 (Cypher 2003). Annual reproductive success is strongly influenced by food availability (Egoscue 1975, White and Garrott 1997) and at one location ranged from 20-100% over a 16-year period (Cypher et al. 2000). Kit Foxes mate for life and are primarily monogamous with occasional instances of polygyny (Egoscue 1962; Ralls et al. 2001, 2007). Young from previous years, typically females, may delay dispersal and assist with raising the current year’s litter (Koopman et al. 2000, Ralls et al. 2001).

The Kit Fox inhabits the deserts and arid lands of western North America. In the United States, it occurs from southern California to western Colorado and western Texas, north into southern Oregon and Idaho. In Mexico, it occurs across the Baja California Peninsula and across northern Sonora and Chihuahua to western Nuevo León, and south into northern Zacatecas (McGrew 1979, Hall 1981).

Not listed on the CITES Appendices. The Kit Fox is considered Vulnerable in Mexico (SEMARNAT 2010). In the United States, the San Joaquin Kit Fox (V. m. mutica) is federally classified as Endangered, and as Threatened by the state of California (USFWS 1998). In Oregon, Kit Foxes are classified as Threatened. In Colorado, Kit Foxes are classified as Endangered. In Idaho, Kit Foxes are considered a protected non-game species. Harvests are not permitted in Idaho, Oregon, or California, and the Kit Fox is a protected furbearer species (i.e., regulated harvests) in Utah, Arizona, Nevada, New Mexico and Texas. In Mexico, the vulnerable status of the Kit Fox grants conservation measures for the species, but these are not enforced. In the United States, state and federal protections for Kit Foxes are being enforced. 
In Mexico, Kit Foxes are found in the Biosphere Reserves of El Vizcaino, Mapimi, El Pinacate and Janos, in the Area of Special Protection of Cuatro Ciénegas, and are probably found in another eight protected areas throughout their range. In the United States, they occur in numerous protected areas throughout their range. The Endangered subspecies V. m. mutica occurs in the Carrizo Plain National Monument and various other federal, state, and private conservation lands.

Efforts are underway to protect the prairie dog towns of both eastern (Pronatura Noreste) and western Mexico (Institute of Ecology from the National University of Mexico), which are known to be strongholds for the Kit Fox, but no specific actions focused on the Kit Fox are being undertaken in Mexico. In the United States, a recovery plan has been completed (USFWS 1998) and is being implemented for the San Joaquin Kit Fox. Recovery actions include protection of essential habitat, and demographic and ecological research in both natural and anthropogenically modified landscapes.

No captive breeding efforts are currently being conducted for Kit Foxes. Facilities such as the Arizona-Sonora Desert Museum in Tucson, Arizona, California Living Museum in Bakersfield, California, and several zoos keep live Kit Foxes for display and educational purposes.

Gaps in knowledge
In general, demographic and ecological data are needed throughout the range of the species so that population trends and demographic patterns can be assessed. In Mexico, available information on the Kit Fox is scarce. The most important gaps in our knowledge of the species are the present distribution of the species and population estimates throughout its range. General biological information is needed from more localities in the Mexican range of the Kit Fox. In the United States, information is needed on the effects of solar energy plants, investigating dispersal patterns and corridors, determining metapopulation dynamics and conducting viability analyses, developing conservation strategies in anthropogenically altered landscapes, assessing threats from non-native Red Foxes, and range-wide population monitoring.

Research in progress in Mexico includes investigations of abundance and diet in the Janos Biosphere Reserve as well as relationships between Kit Foxes and sylvatic plague. Research in progress on the endangered San Joaquin Kit Fox include investigations of solar energy development effects, trophic interactions, urban ecology, population genetic structure, ecology in core and satellite population areas, and population effects of sarcoptic mange. Research in progress elsewhere in the USA includes abundance and ecology in Oregon, detection and ecology in Idaho, survey methods in low-density areas, interactions with coyotes near artificial water sources in Utah, effects of off-highway vehicles in Arizona, and distribution and occupancy in New Mexico.