‹ Compare two snakes
Prairie Rattlesnake vs Western Rattlesnake
Tap a part to see it on both. Tap it again to turn it off.
Scott Shupe, no rights reserved
Prairie Rattlesnake
Crotalus viridis
Venomous(c) Yan Davidovich, some rights reserved (CC BY-SA)
Western Rattlesnake
Crotalus oreganus
VenomousThe quick way to tell
These two look very alike and their ranges overlap. Where you found it is often the best clue.
Where it lives ★ This settles it
Great Plains from southern Canada through Montana, the Dakotas, Wyoming, Nebraska, Kansas, Colorado, western Oklahoma and west Texas, west into eastern Idaho, eastern Utah, New Mexico and northeastern Arizona.
Pacific states and the Great Basin: Washington, Oregon, Idaho, California, Nevada, Utah and Arizona, east into western Colorado and southwestern Wyoming, plus British Columbia and Baja California.
Head
Broad triangular head, clearly wider than the neck, with two pale diagonal stripes on the cheek.
Broad triangular head with a dark cheek stripe bordered by white.
Pattern
Pale-edged blotches tightening into bands near the tail; colour matches local soil.
Pale-edged blotches wider than long, banding near the tail; olive to nearly black.
Eyes
Vertical slit pupil; heat-sensing pit between eye and nostril.
Vertical slit pupil; heat-sensing pit between eye and nostril.
Pits
A deep heat-sensing pit on each side of the face, between the eye and the nostril.
A deep heat-sensing pit on each side of the face, between the eye and the nostril.
Tail
Thinner than the body; tail rings dull, not bold black and white, ahead of the rattle.
Thin ahead of the rattle.
What it does
Coils and rattles loudly; holds ground rather than fleeing.
Coils and rattles; retreats to rocks if given room.