I have been seeing tracks of snowshoe hares during my outings in the Turtle Mountain forest, although I have yet to see one. It might surprise you, but they are native to North Dakota. Historically they could be found in Turtle Mountain, Pembina Hills, around Devils Lake, Killdeer Mountains, and wooded areas along the Red, Mouse, and Missouri Rivers.
Snowshoe hares, of course, are well known for their population cycles.
These cycles are not well understood, but when browsed heavily, some trees and shrubs produce new growth that is low in nutrition and high in defense chemicals. These defense chemicals may make the plant material toxic, bitter, or less desirable to browsing animals. So if the hare population is high enough that they over-browse the normal winter food sources of buds, twigs, and bark, their food supply may soon become unusable. Add predation and other winter mortality factors, and the population plummets. A year or two later, as the plants become more palatable and nutritious, the population rebounds and he cycle starts all over again.
North Dakota is also home to a few of their close relatives. Most everyone is familiar with the white-tailed jackrabbit. They have been documented in every county in the state.
Our most commonly observed rabbit is the eastern cottontail. It too has been documented in every county in the state. However, they may not be native to North Dakota. Robert Seabloom in his Mammals of North Dakota notes that the first reports of the eastern cottontail in North Dakota did not occur until 1890.
If you see a “cottontail” with disconcertingly large ears in the badlands, it is probably the desert (or Audubon’s) cottontail. It is a species of the more arid areas in western North America. The large ears are the main distinguishing characteristic, and it is also a bit larger than the eastern cottontail.
The mountain (or Nuttall’s) cottontail, a western species, reaches its eastern limit in the Black Hills and extreme western North Dakota. Seabloom notes early records of it in Williams, McKenzie, and Billings counties. More recently, however, the species has not been documented in North Dakota even though it has been documented just across the state line in Wibaux County, Montana. There may be a few in the badlands, but Seabloom speculates that the eastern cottontail may have displaced the mountain cottontail in the badlands.