Swift Fox (Vulpes velox)

Status:  Endangered

Description:

The Swift Fox, named for its speed, is the smallest of the North American wild dogs. It is well adapted for speed with its lean, long body and long legs. Some individuals have been recorded at speeds of more than 60 kilometres an hour.

The adult weighs between two and three kilograms. The fox’s total body length is 84 centimetres of which its tail makes up 28 centimetres. It stands about 30 centimeters tall. The lower legs and body are a soft grey colour with an orange or tan tinge. The throat, chest and belly are white to buff brown in colour. The Swift Fox has large ears (8 centimetres) and dark bright eyes.

Characteristic features that distinguish the Swift Fox from the Red Fox (Vulpes vulpes) are its small size, the black spots on its muzzle, the grey back and the long black-tipped bushy tail.

Status:

In 1978, the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) listed the Swift Fox as extirpated. Due to reintroduction programs, the Swift Fox was down-listed from extirpated to endangered in 1999. The Swift Fox is given full protection on private, provincial and federal lands under Section 52(1), part (V) of the Wildlife Act, 1997. In addition, Section 5(1) of the Wild Species at Risk Regulations (1999) provides protection for Swift Fox dens.

The Swift Fox was once common across the Canadian plains. Its range extended from Pembina Hills in southwest Manitoba to the foothills of the Rocky Mountains and south to Texas. The Swift Fox declined rapidly in the late 1800s and early 1900s. Between 1853 and 1877, the Hudson’s Bay Company averaged 4,681 Swift Fox pelts each year. By the early 1920s, they averaged 500 pelts. In 1928, the last Canadian specimen was killed in Govenlock, Saskatchewan.

Habitat:

Swift Foxes prefer short or mixed-grass prairie with sparse vegetation and flat to gently rolling terrain. These conditions allow for good mobility and visibility for hunting prey and detecting predators. Native grasses and shrubs common in these areas include blue gamma grass (Bouteloua gracilis), spear grass (Stipa comata), fescue grass (Fescue spp.) and pasture sage (Artemisia frigida). Coulees, brushy areas and cultivated lands are usually avoided. Swift Fox habitat must include extensive tracts of native grassland, burrowing mammals and suitable soil types for denning.

Multiple den sites may be used throughout the year for shelter, rearing young and as escape routes from predators. Swift Foxes will modify existing burrows dug by Badgers (Taxidea taxus) and Richardson’s Ground Squirrels (Spermophilis richardsonii). The presence of these animals is considered crucial, although Swift Foxes will also dig new dens.

Life Cycle:

Swift Foxes are opportunistic feeders. This means they will eat whatever is available to them. They mainly eat mice, cottontail rabbits (Sylvilagus floridanus) and carrion (dead animals). Other foods include small mammals, birds, insects (grasshoppers and beetles), reptiles and amphibians. Usually the Swift Fox relies on stealth to catch its prey but occasionally its speed allows it to catch a jackrabbit (Lepus townsendii).

Swift Foxes are mainly nocturnal. Daytime activity usually occurs only in the den, although adults can sometimes be seen sunning themselves near their dens (morning and evenings during the summer and in midday during the winter). The Swift Fox is a curious animal, making it susceptible to trapping and poisoning. This probably contributed to the animal’s extirpation.

Dens are used by Swift Foxes throughout the year for both escape cover and raising pups. Simple dens with a single burrow and entrance are thought to be used mainly for protection. More complex dens with interconnected tunnels and multiple entrances are used for raising pups.

Young foxes can breed in their first year. Swift Foxes usually mate for life. Breeding occurs from January to March and gestation is approximately 50 days. Pups born in captivity in Canada are usually born from mid-April to mid-May. As few as one pup can be born or as many as eight pups have been recorded. The average litter contains four or five pups.

The pups are born blind and helpless and rely completely on the female who stays under ground while the male hunts for food. Their eyes open around 10 to 15 days after birth and after two weeks the pups weigh around 200 grams. The pups are weaned between six and seven weeks and two months after birth they look like adults. Adult foxes will often move pups to different dens throughout the summer as parasites such as mites, fleas and ticks may build up in large amounts in the dens. Human disturbance will also cause foxes to change dens.

Young foxes stay with their parents for four or five months and they leave in early fall. If population densities are low, the pups may establish territories near their parents. If habitat around their parents' territory is already occupied, they have been known to travel up to 80 kilometres in search of a new home. In the wild, Swift Foxes can live between eight and 10 years. In captivity, they have been known to live up to 13 years.

Limiting Factors/Recovery Needs:

It is not clear why the Swift Fox disappeared from the Canadian prairies, although human disturbances were a factor. Swift Foxes require large areas of native prairie. As agricultural activities began to increase, native prairie was converted into cultivated crops. Habitat destruction from these activities, combined with the use of pesticides and herbicides has decreased the quantity and quality of habitat for the Swift Fox.

Hunting, trapping, predator and rodent poisoning also contributed to the extirpation of the Swift Fox. They were victims of poisoning campaigns directed at other animals such as coyotes (Canis latrans), wolves (Canis Lupus) and ground squirrels.

The main factor threatening the reintroduction of the Swift Fox is predation. Canada’s Swift Fox population has an annual mortality rate of one third to one half. Coyotes are responsible for 80 per cent of these deaths. Coyotes may see foxes as competitors for food and space because they kill but seldom eat them.

Recovery Actions:

Efforts to recover the Swift Fox began in 1973 when Miles and Beryl Smeeton imported two pairs of Swift Foxes from Colorado and established a captive breeding program. The Smeetons are owners of the Wildlife Reserve of Western Canada located near Cochrane, Alberta.

In 1983, a program was initiated to reintroduce the Swift Fox to parts of its historical Canadian range. Organizations actively involved included the Canadian Wildlife Service, the University of Calgary, Cochrane Ecological Institute, the Calgary Zoo, World Wildlife Fund, Swift Fox Conservation Society, Parks Canada (Grasslands National Park) and the Saskatchewan and Alberta governments.

In 1989 the National Swift Fox Recovery Program was established by RENEW (Recovery of Nationally Endangered Wildlife). The first task was to conduct a three year study to determine if suitable habitat still remained in the Canadian prairies for the Swift Fox. Following the study, a National Recovery Plan was developed for the species in 1996. The primary goal of the plan was to remove the Swift Fox from the endangered species list by increasing populations to self-sustaining levels by the year 2000.

Long term objectives of the recovery plan are to establish two geographically separated core populations by the year 2000, identify and secure key Swift Fox habitat on two core areas of the Canadian prairies and ensure the establishment of the Swift Fox in at least 50 per cent of its remaining suitable habitat on the Canadian range.

Between 1983 and 1997, approximately 942 Swift Foxes were released in southern Alberta and Saskatchewan. During the reintroduction program, both wild-born and captive-raised foxes have been used. Captive-reared foxes were supplied by the Cochrane Ecological Institute, Calgary Zoo, Edmonton Valley Zoo and the Moose Jaw Wild Animal Park. Between 1992 and 1997, the program focused on releasing wild-born foxes whenever possible. Swift Foxes captured in the United States were translocated to Canada and used for both captive breeding and wild releases. Research has shown that wild-born animals have a better survival rate, reproduce more successfully and cost less than captive-reared animals.

In 1997, the Swift Fox was given full protection in Saskatchewan on private, provincial, and federal lands under section 52(1), part V of The Wildlife Act. Swift Fox dens are also protected under section 5(1) of the Wild Species at Regulations (1999).

No animals have been released since 1996. A census on the Canadian Swift Fox population was conducted in 1996 to 1997 as part of the National Swift Fox Recovery Plan. The purpose was to evaluate the success of the reintroduction. The population was estimated to be around 289 foxes. The Swift fox population is currently being assessed and population estimates should be updated in spring 2001. Initial data is promising, suggesting that Swift Fox populations are increasing. This census should evaluate the viability of the population and determine if more releases are required to reach the sustainable population goals.

Please contact your local library or visit the Internet sites below for more information on the Swift Fox.

Carbyn, Ludwig N. 1998. Update COSEWIC status report on swift fox (Vulpes velox). The Committee on the Status of Endangered Wildlife in Canada. 62pp.

Environment Canada. 1999. Hinterland who’s who: swift fox. Canadian Wildlife Service. [Online]
     http://www.cws-scf.ec.gc.ca/hww-fap/fox/fox.html