The Northern Pacific Rattlesnake (Crotalus oreganus oreganus), also known as the Western Rattlesnake, is the only native venomous snake species found in Washington state.
Where Rattlesnakes Are Found
Rattlesnakes are predominantly found in eastern Washington. These snakes prefer arid and semi-arid environments, including shrub-steppe, grasslands, and rocky areas with sun exposure. They are commonly encountered near the Columbia River Gorge and its tributaries, such as Crab Creek and the Yakima River Canyon. Specific areas like Moses Lake, Lake Wenatchee, and the Sunnyside Snake River Wildlife Area are known habitats. Rocky landscapes and available prey provide suitable conditions.
Rattlesnakes emerge from dens in April and May, returning to them for hibernation. Dens are found among rocks, offering warmth and protection. While they prefer drier habitats, they can also be found in brush-land, woodlands, and sometimes along streams.
How to Identify Rattlesnakes
The Northern Pacific Rattlesnake has distinct physical characteristics. They typically range from 18 inches to four feet long, though some can reach up to 64 inches. Their heads are notably triangular and wider than their necks, distinguishing them from many non-venomous snakes.
A defining feature is the rattle at the end of their tail, with a new segment added each time the snake sheds its skin. They also have vertical, slit-like pupils and heat-sensing pits located between their eyes and nostrils. Their coloration varies, often appearing greenish-brown, greenish-gray, or shades of brown, tan, or olive, with dark blotches along their back that may be diamond-shaped. Blotches become more like crossbands towards the tail, with the last two rings often black.
Encountering Rattlesnakes Safely
Rattlesnakes prefer to avoid human interaction and are not aggressive unless provoked. If you encounter a rattlesnake, remain calm and slowly back away to a safe distance, typically beyond the snake’s striking range, which can be up to half its body length. If you hear a rattle, try to locate the snake before moving to avoid placing it in a more threatened position.
When in rattlesnake country, wear long pants and closed-toe shoes or boots that cover your ankles. Stay on designated trails, as rattlesnakes are less likely to be found in heavily trafficked areas. Avoid stepping or reaching into unseen areas like dense brush, tall grass, or rock piles, which are common hiding spots. Using hiking poles can help probe ahead on the trail and move vegetation.
If a rattlesnake bite occurs, seek immediate medical attention by calling 911 or the Washington Poison Center at 1-800-222-1222. While awaiting medical help, keep the bitten area still and below heart level to slow the spread of venom. Remove rings, watches, or constricting items from the affected limb, as swelling is expected. Do not suck out venom, cut the wound, apply ice, or use a tourniquet, as these actions can cause more harm. Do not try to capture or kill the snake.