Prairie Rattlesnake

A snake coiled on dirt

The prairie rattlesnake is one of six reptile species and the largest species found in Yellowstone.



Scientific name

Crotalis viridis viridis


  • Can be more than 48 inches in length.
  • Greenish gray to olive green, greenish brown, light brown, or yellowish with dark brown splotches down its back that are bordered in white.

Habitat and Behavior

  • Only dangerously venomous snake in the park.
  • Lives in the lower Yellowstone River areas of the park, including Reese Creek, Stephens Creek, and Rattlesnake Butte, where the habitat is drier and warmer than elsewhere in the park.
  • Usually defensive rather than aggressive.
  • Only two snake bites are known during the history of the park.

Did You Know?