Western Ratsnake (formerly Black Ratsnake or Texas Ratsnake)
Pantherophis obsoletus • Order: Squamata; Suborder: Serpentes; Family: Colubridae; Subfamily: Colubrinae; Genus: Pantherophis; Species: P. obsoletus
Distributed across North America from the Mississippi River west to the Rocky Mountains, and from southern Canada down through Texas and northern Mexico.
Look up Western Ratsnake (formerly Black Ratsnake or Texas Ratsnake) in the Snake Encyclopedia →Venomous Status
Non-venomous; lacks fangs and venom glands.
Danger Level
Harmless; though they may bite or musk if handled, they pose no significant threat to humans or pets.
Family
Order: Squamata; Suborder: Serpentes; Family: Colubridae; Subfamily: Colubrinae; Genus: Pantherophis; Species: P. obsoletus
Conservation
Least Concern (IUCN); widespread and common, though they face threats from habitat fragmentation and road mortality.
Physical Description
Characterized by a greyish-silver to brown base color with dark blotches. The head is wider than the neck, eyes have round pupils, and scales are weakly keeled. In many regions, adults can become almost solid black.
Size & Dimensions
Large-bodied snake. Adults typically range from 100 to 180 cm (3-6 feet). This specimen appears to be a sub-adult or juvenile based on the distinct blotching.
Habitat
Highly adaptable; found in hardwood forests, prairies, rocky canyons, agricultural areas, and suburban backyards. Highly arboreal and often found in trees or rafters.
Behavior & Temperament
Diurnal and crepuscular. They are known to 'kink' their bodies when threatened to break up their silhouette. They may rattle their tails in dry leaves to mimic a rattlesnake.
Diet & Feeding
Specializes in rodents and birds. They are powerful constrictors that often forage actively and climb trees to find bird nests.
Reproduction
Oviparous (egg-laying). Females lay clutches of 10-30 eggs in early summer, which hatch in late summer or 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 Gopher Snake (Pituophis catenifer), which has heavier keeling and a different head shape.
Conservation Status
Least Concern (IUCN); widespread and common, though they face threats from habitat fragmentation and road mortality.
Cultural Significance
Ecologically vital for rodent control. They are frequently found in barns and homesteads, leading to their common nicknames based on their utility as 'mousers'.
Notable Features
Superb climbers, they can scale vertical tree trunks using their specialized ventral scales to grip bark. They are famous for being found in 'impossible' high-up places like birdhouses and attic vents.