Western Rat Snake
Pantherophis obsoletus • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Colubrinae, Genus: Pantherophis, Species: P. obsoletus
Natural to central United States, ranging from the Mississippi River west to the Rocky Mountains, and from southern Canada down to the Gulf of Mexico (including Texas, Oklahoma, Kansas, and Missouri).
Look up Western Rat Snake in the Snake Encyclopedia →Venomous Status
Non-venomous (Aglyphous)
Danger Level
Harmless. They are not a threat to humans or pets; however, large adults may strike or musk if cornered or handled roughly.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Colubrinae, Genus: Pantherophis, Species: P. obsoletus
Conservation
IUCN Least Concern. Faces threats from habitat fragmentation and intentional killing due to confusion with venomous species.
Physical Description
Large, powerful body with a faint blotched pattern on a dark grey or black background. The head is slightly wider than the neck, eyes have round pupils, and the scales are weakly keeled. The belly is usually white or cream with dark mottling.
Size & Dimensions
This specimen appears to be an adult approximately 4-5 feet long. The species typically ranges from 3.5 to 6 feet, with record lengths reaching nearly 8 feet.
Habitat
Highly adaptable to diverse environments including hardwood forests, swamps, rocky hillsides, and farm fields. Often found near human dwellings in barns and residential decks where rodents are present.
Behavior & Temperament
Primarily diurnal or crepuscular, becoming more nocturnal in hot weather. They are excellent climbers (often found in trees) and utilize a 'kinked' posture when threatened to break up their silhouette. Generally docile but will bite or release a foul-smelling musk if threatened.
Diet & Feeding
Generalist predator that uses constriction. Diets consist primarily of rodents, birds, and eggs. They are active foragers that frequently enter structures while hunting.
Reproduction
Oviparous; females lay clutches of 10 to 30 elongated eggs in mid-summer, typically in hollow logs, mulch piles, or leaf litter. Hatchlings emerge in autumn.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Often confused with the North American Racer (Coluber constrictor), which has smooth scales, or the venomous Cottonmouth/Copperhead due to patterns in younger specimens; however, the Rat Snake's climb-focused body and round pupils distinguish it.
Conservation Status
IUCN Least Concern. Faces threats from habitat fragmentation and intentional killing due to confusion with venomous species.
Cultural Significance
Highly valued by farmers and homeowners for their natural role in rodent control. Often featured in North American folklore as the 'pilot' snake.
Notable Features
Distinguished by its incredible climbing ability and the tendency to assume a 'crinkled' or 'wavy' body shape when stationary, which serves as camouflage against linear shadows.