Pronghorn: Racers on the Great Plains

Badlands National Park provides a home for the pronghorn, which is sometimes called the pronghorn antelope. Despite its nickname, the pronghorn is not actually a true antelope. However, it shares several characteristics with genuine antelopes found in Africa and Asia. These similarities are the result of convergent evolution, in which unrelated animals independently develop comparable traits because they face similar environmental conditions. The pronghorn is the only surviving species in the family Antilocapridae, and its closest living relatives are actually giraffes.

A Day in the Life

At a distance, pronghorns can sometimes be mistaken for deer, but their differences become obvious when viewed more closely. Pronghorns are generally smaller than deer and stand about three feet tall at the shoulder. They are recognizable by the bright white patches of fur on their rump, sides, underside and throat.

Male pronghorns develop distinctive branching horns that can reach approximately one foot in length, which is the feature that gives the animal its name. Females may also have horns, but theirs are much shorter and generally straight. Their horns differ from deer antlers because they grow around a permanent bony core covered by skin rather than being shed entirely. However, like the horns of a bison, the outer keratin sheath is shed and subsequently replaced.

Pronghorns inhabit open prairie landscapes throughout western North America, ranging from parts of Canada to Mexico. They are herbivores that feed on shrubs, grasses and various flowering plants growing across the plains. The wide, unobstructed prairie also gives them an important advantage when predators approach: their extraordinary running ability.

Need for Speed

Speed is perhaps the most remarkable characteristic of the pronghorn. Their long legs, lightweight bodies, large windpipes and cushioned hooves allow them to maintain speeds of around 55 miles per hour for roughly half a mile. They can also travel at speeds close to 45 miles per hour over considerably longer distances.

No modern predator living within the pronghorn's range is capable of matching this remarkable pace, which has long intrigued scientists. Researchers believe this extraordinary speed may have evolved as a defense against the American cheetah, a remarkably fast ambush predator that once inhabited North America. The American cheetah disappeared from the continent approximately 12,000 years ago, but the pronghorn's impressive speed remains.

Pronghorns in the Badlands

Within Badlands National Park, pronghorns are most commonly encountered in large, uninterrupted grassland areas. In the North Unit, visitors may spot them in the grasslands north of Badlands Loop Road, also known as Highway 240, as well as in the Buffalo Gap National Grassland bordering the park.

Pronghorn sightings have also been recorded both above and below Sheep Mountain Table, near the boundary between the North Unit and South Unit. Their preference for open grassland makes these areas particularly suitable places to look for these remarkably fast animals.