Swift foxes are primarily nocturnal, but can sometimes be seen sunning themselves near the entrance to a den. They live on prairie grasslands just east of the Rocky Mountains. Like other foxes, they face many dangers: coyotes prey on them, and they are susceptible to trapping, poisoning, and being hit by automobiles. Disease, den cave-ins, and starvation also cause mortality. Habitat destruction has greatly reduced their available habitat. In Canada, swift foxes are protected as an endangered species and attempts are being made to reintroduce them in the Canadian prairie provinces.

Links:
Mammal Species of the World
Click here for The American Society of Mammalogists species account