Swift Fox (Vulpes velox)
Official Status: Removed from the Federal list of candidate species in January 2001. For more information see the swift fox news release at the Fish and Wildlife Service's, Mountain-Prairie Region homepage.
Historical Status: Historically, the swift fox was widely distributed from southern Canada to the panhandle of Texas, and from northwest Montana to western Minnesota. The swift fox once inhabited all of North Dakota's prairies.
Present Status: Swift fox populations have been reduced to about 40 percent of their former range. The swift was extirpated in Canada, but the animal has been recently reintroduced in Saskatchewan. Swift fox populations are still healthy in the southern United States. In North Dakota, no swift fox sightings were reported from 1915 to 1970. In 1970, a swift fox carcass was found in Slope County. In 1976 and in 1990, single individuals were observed in North Dakota in Mercer County and Golden Valley County. Swift fox are apparently absent from North Dakota, although several recent observations suggest the species may exist in extremely low densities in the southwestern counties.
Habitat: The swift fox prefers short- to mid-grass prairies with little or no shrubs. They also inhabit areas of mixed agricultural use, but in these areas, population densities are lower. Prairie dog towns are a preferred habitat of swift fox.
Life History: Swift fox breed when they are 1 to 2 years old. Breeding occurs in February and early March, with the gestation period being 52-53 days. The average litter size is 4 to 5 pups. The young emerge from the dens at 3 to 4 weeks and are weaned at 6 to 7 weeks. The young will stay with the adults about 4 or 5 months. Swift fox can live up to 10 years in the wild. Dens are used on a daily basis all year round. Dens may be excavated by the swift fox or they may use old badger holes or prairie dog burrows. Prairie dogs, rabbits, small birds, insects, and plant parts make up the main portion of the diet. Swift fox readily feed on carrion. Swift fox are primarily nocturnal (come out at night). Coyotes, eagles, and hawks have been reported as predators of swift fox. Coyotes have probably become a more severe predator of the swift fox, since the extirpation of the prairie wolf. In pre-settlement times, the prairie wolf controlled coyote numbers and hence, protected the swift fox.
Aid to Identification: The swift fox averages 5 pounds and measures about 3 feet from head to tail. It is about the size of a house cat. The color is orangeish-tan on the back, fading to a light tan on the belly. The tip of the tail is black and there are black spots on the muzzle. The swift fox is about one-half the size of the red fox. The red fox has a white-tipped tail. The swift fox is found only on the western prairies, while the larger gray fox is found only in the eastern forests.
Reasons for Decline: The swift fox has declined as a consequence of the increase in agriculture and the disappearance of the native prairies. Widespread shooting, trapping, and poisoning campaigns aimed at wolves, coyote, and red fox also reduced swift fox populations. Swift fox are very easy to trap and very susceptible to poisoned bait. They also get hit by cars when foraging along the sides of roads.
Recommendations: Notify the Fish and Wildlife Service if you observe a swift fox in North Dakota.
Comments: The taxonomy of the swift fox has been a source of confusion and debate. Many researchers now dispute the old claim of there being a Northern swift fox and a Southern swift fox. Some recent publications have suggested that the swift fox and the kit fox (Vulpes macrotis) of the southwestern deserts of the United States are actually the same species. There have been several petitions to list the swift fox as endangered or threatened, but the requests were determined to be not warranted. Swift fox were historically trapped for their fur, but their pelts are of low quality and small in size.
References: Conservation Assessment and Conservation Strategy for Swift Fox in the United States, by Kahn et al., September 1997. Report on the Status of the Swift Fox, Vulpes velox, a Category 2 Taxon, in North Dakota, by U.S. Fish and Wildlife Service, 1990 (unpublished).
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