• A bull elk bugles in Yellowstone National Park

    Yellowstone

    National Park ID,MT,WY

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  • Craig Pass Closed for the Season; Mammoth to Norris Closed Sept. 14-30

    The road linking West Thumb and Old Faithful is closed for the season—traffic should detour through West Thumb, Lake, and Canyon. The road from Mammoth to Norris is closed for two weeks—traffic should detour over Dunraven Pass. More »

Bull snake

bull snake
Bull snake
NPS/Peaco
 
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 gopher snake its name.
  • 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.

Did You Know?

Yellowstone Wolf.

There were no wolves in Yellowstone in 1994. The wolves that were reintroduced in 1995 and 1996 thrived and there are now over 300 of their descendents living in the Greater Yellowstone Area.