A herd of pronghorn on a hill

Pronghorn evolved in North America 20 million years ago. They can run sprints at 45–50 miles per hour, an adaptation to outrun an extinct cheetah.



The North American pronghorn (Antilocapra americana) is the surviving member of a group of animals that evolved in North America during the past 20 million years. It is not a true antelope, which is found in Africa and southeast Asia. The use of the term “antelope” seems to have originated when the first written description of the animal was made during the 1804–1806 Lewis and Clark Expedition. Learn More: Pronghorn Information Continued...


Quick Facts

Number in Yellowstone


Where to See

  • Summer: Lamar Valley; some may be near the North Entrance near Gardiner, Montana.
  • Winter: between the North Entrance and Reese Creek.

Behavior and Size

  • Male (buck) weighs 100–125 pounds; female (doe) weighs 90–110 pounds; adult length is 45–55 inches and height is 35–40 inches at shoulder.
  • Average life span: 7–10 years.
  • Young (fawns) born in late May–June.
  • Live in grasslands.
  • Can run for sustained sprints of 45–50 mph.
  • Eat sagebrush and other shrubs, forbs, some grasses.
  • Both sexes have horns; males are pronged.


  • Prior to European American settlement of the West, pronghorn population estimated to be 35 million.
  • Early in the 1800s, pronghorn were abundant in river valleys radiating from Yellowstone; settlement and hunting reduced their range and numbers.
  • Park management also culled pronghorn during the first half of the 1900s due to overgrazing concerns.

Management Concerns

  • Pronghorn are a species of special concern in the park.
  • This small population could face extirpation from random catastrophic events such as a severe winter or disease outbreak.

More Information

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