Bullsnake

A tan and black snake on rocky surface
Bullsnakes are one of six reptile species found in the park.

NPS/Neal Herbert

 

Scientific Name

Pituophis catenifer sayi

Identification

  • A subspecies of the gopher snake, is Yellowstone’s largest reptile, ranging from 50 to 72 inches long.
  • Yellowish with a series of black, brown, or reddish-brown blotches down the back; the darkest, most contrasting colors are near the head and tail; blotches are shaped as rings around the tail.
  • Head resembles a turtle’s in shape, with a protruding scale at the tip of the snout and a dark band extending from the top of the head through the eye to the lower jaw.

Habitat

In Yellowstone, found at lower elevations; drier, warmer climates; and open areas such as near Mammoth.

Behavior

  • Lives in burrows and eats small rodents—behavior that gave the bullsnake another common name: gopher snake.
  • Often mistaken for a rattlesnake because of its appearance and its defensive behavior: when disturbed, it will coil up, hiss loudly, and vibrate its tail against the ground, producing a rattling sound.
 
The head of a brown spotted snake among grass

Reptiles

There are six reptile species in Yellowstone.

A tan and brown spotted snake with rattler in a coil

Prairie Rattlesnake

Prairie rattlesnakes are the only dangerously venomous snakes in Yellowstone.

A brown snake on gravel next to a human hand

Rubber Boa

Rubber boas are usually found in rocky areas near streams or rivers with nearby shrubs or trees.

A dark gray, tan, and white striped lizard with small spikes on gravel

Sagebrush Lizard

The sagebrush lizard is the only lizard in Yellowstone.

A black and white snake on dead grass

Common Gartersnake

Common gartersnakes are only found in southern parts of the park.

A white and tan striped snake with black dots on a rock

Terrestrial Gartersnake

Terrestrial gartersnakes are the most common reptile in Yellowstone.

Last updated: June 14, 2017

Contact the Park

Mailing Address:

P.O. Box 168
Yellowstone National Park, WY 82190-0168

Phone:

(307) 344-7381

Contact Us