Washington State is home to approximately seven native snake species that have adapted to the region’s diverse geography. The vast majority are completely harmless to humans and play an important role in controlling local rodent and insect populations. The cool, wet climate west of the Cascade Mountains limits the overall snake population, but warmer, drier habitats to the east allow several species to thrive.
The Single Venomous Species
Washington is home to only one venomous species, the Western Rattlesnake (Crotalus oreganus). This pit viper is identifiable by the characteristic rattle segments on its tail, used as a defensive warning. It possesses a broad, triangular head, distinctly wider than its neck, which houses the venom glands. Western Rattlesnakes are typically brown, olive, or tan, often featuring a diamond-shaped pattern along the back.
They are primarily found in the arid and rocky habitats of eastern and south-central Washington, preferring slopes and sun-exposed outcroppings for den sites. If encountered, maintain distance and never attempt to handle it. Immediate medical attention is necessary in the rare event of a bite.
Common Non-Venomous Residents
The most frequently encountered snakes are the various species of Garter Snakes, including the Common, Northwestern, and Western Terrestrial Garter Snakes. These slender snakes are found in a wide variety of habitats, commonly preferring damp areas near water sources like ponds and streams. Garter Snakes are easily recognized by three light-colored stripes—one down the back and one on each side—against a dark background. They are small to medium-sized, docile, and pose no threat, often relying on a foul-smelling musk as a defense mechanism.
Another widespread non-venomous resident, particularly in Eastern Washington, is the Gopher Snake (Pituophis catenifer). This is a large, robust snake that can reach lengths of four to six feet, often appearing tan with dark brown blotches. Gopher Snakes are frequently mistaken for rattlesnakes because they mimic the venomous species by coiling, loudly hissing, and vibrating their tail against dry vegetation. Unlike the rattlesnake, the Gopher Snake has a slender head and lacks a rattle.
The Western Yellow-Bellied Racer (Coluber constrictor mormon) is common in the arid eastern half of the state. Racers are known for their speed and agility, often moving quickly through open areas with their head slightly raised. Adults typically have a uniform coloration of olive, brown, or gray above, contrasting with a pale, often yellowish belly. These snakes are highly active predators of rodents and insects.
Unique Washington State Snakes
Among Washington’s snake population is the Northern Rubber Boa (Charina bottae), a representative of the boa family. This species is found across nearly all of Washington, preferring the cooler, moist conditions of forests and grasslands. The Rubber Boa is distinctively small, stout, and smooth, with loose, glossy skin that gives it the appearance of rubber.
A remarkable characteristic is its blunt, thick tail, which closely resembles its head, earning it the nickname “two-headed snake.” This feature is a defense strategy where the snake raises its tail to distract a predator from its actual head. Rubber Boas are known for their gentle temperament and are non-aggressive. Another secretive species is the Sharp-tailed Snake (Contia tenuis), a small reptile rarely seen, which spends most of its life hidden under rocks, logs, and forest debris.
Regional Distribution and Coexistence Tips
Snake distribution is strongly influenced by the Cascade Mountain range, which creates a noticeable divide between habitats. Eastern Washington, characterized by arid shrub-steppe environments, hosts a higher density of snakes, including the Western Rattlesnake, Gopher Snake, and Racer. Western Washington, with its cooler, wetter climate, has a lower snake density, where the most common sightings are Garter Snakes and the Rubber Boa.
When recreating in snake country, particularly in the eastern part of the state, adopting simple habits promotes safety. Always stay on designated trails, as many species use rocks and tall grasses for cover and basking. Wearing sturdy boots and long pants offers protection when hiking through brushy areas. If a snake is encountered, stop, give the animal a wide berth, and allow it to move away undisturbed.