Photo: USFWS 

Standing in the tall grasses of the plains surrounding the river, the Lewis and Clark Expedition first noticed “several wild goats” – at least that’s what they thought the animal was. It was early September 1804 and the Corps of Discovery was moving along today’s northern Nebraska and southern South Dakota. About 10 days later, William Clark shot one of the animals and when he inspected it he thought its eyes were like a sheep’s and its body was like an African antelope’s.

Sergeant Ordway wrote, “…it was 3 feet high resembles a Deer in some parts. the legs like a Deer. feet like a Goat. horns like a Goat only forked Turn back picked hair thick & of a white a dark redish coullour. Such an anamil was never yet known in U. S. States.” The men struggled with a name for this new-to-them mammal. First they tried cabre, the Spanish word for goat, spelling it cabra, cabree, and cabrie. Captain Lewis, impressed by the animal’s graceful fleetness, settled on “antelope.”

We know it as the pronghorn (Antilocapra americana), the only surviving member of the Antilosapridae family, that has been in North America for millions of years.

With a deer-like body, pronghorns weigh between 90 and 120 pounds and stand about 3.5 feet tall from feet to top of the shoulder. They’re the only known animal to have branching hollow horns that are shed every year. And they’re the fastest running animal in North America – clocked at close to 50 miles per hour.

Lewis & Clark National Historic Trail

Last updated: April 2, 2021