The swift fox, a small canine similar in size to a domestic cat, is a distinctive inhabitant of North America’s prairies. Known for its speed, this species plays a role in prairie ecosystems. Understanding their current habitats and preferences offers insight into their survival and the health of grassland environments.
Current Geographic Range
Swift fox populations are found in fragmented areas across North America’s western grasslands, a significant reduction from their historical distribution. In the United States, they inhabit parts of Montana, Colorado, New Mexico, Kansas, Oklahoma, and Texas. Populations are lower in Nebraska and South Dakota, but more abundant in Colorado, Kansas, and Wyoming.
Within Canada, swift foxes primarily reside in southern Alberta and Saskatchewan, where they were once extirpated but have since been reintroduced. The Canadian population, along with an adjacent Montana group, is geographically and genetically distinct from the main swift fox range in the United States. Overall, swift foxes presently occupy approximately 44% of their historical range in the United States and only about 3% in Canada.
Habitat Preferences
Swift foxes prefer open, sparsely vegetated environments that offer clear visibility and ease of movement. They are primarily found in shortgrass and mixed-grass prairies, and arid grasslands. These areas feature flat to gently rolling terrain with low-growing vegetation like buffalo grass, bluestem, and wire grass, allowing foxes to scan for prey and predators.
The soil composition of their habitat is also important, with a preference for well-drained, loamy soils that facilitate den construction. Swift foxes use dens year-round for protection from extreme weather, to escape predators, and for raising their young. They may dig their own burrows or enlarge existing ones made by other animals like prairie dogs or badgers.
Historical Shifts in Distribution
Historically, the swift fox was widespread across the Great Plains of North America, extending from Alberta in Canada south to Texas, and from western Iowa to Montana. Their historical range is estimated to have been approximately 1.5 million square kilometers. This expansive distribution covered the shortgrass and mixed-grass prairies that characterized much of the central continent.
Following European settlement, swift fox populations significantly declined and their distribution retracted. By the late 1800s, the species had largely disappeared from northern parts of its historical range, including Canada, where the last specimen was collected in 1928. Populations were severely depleted across the rest of their range, leading to near extinction in some areas by the early 1900s. This contraction resulted in the fragmented distribution seen today.