Montana
Snakes in Yellowstone County
8 species have been documented here, 1 of them venomous.
Venomous snakes in Yellowstone County
Full guide & what to do if bitten →
Prairie RattlesnakeCrotalus viridisVenomousHeavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
Every snake recorded in Yellowstone County
Western Terrestrial Garter Snake
Thamnophis elegans
Harmless
Gopher Snake
Pituophis catenifer
Harmless
Common Garter Snake
Thamnophis sirtalis
Harmless
North American Racer
Coluber constrictor
Harmless
Prairie Rattlesnake
Crotalus viridis
Venomous
Western Milksnake
Lampropeltis gentilis
Harmless
Eastern Milksnake
Lampropeltis triangulum
Harmless
Plains Hognose Snake
Heterodon nasicus
Harmless
Compiled from verified GBIF & iNaturalist observations. Informational only.