How to Identify the Bull Snake (Identification Guide)

Key identifying features

The bull snake (Pituophis catenifer sayi), a subspecies of gopher snake, is one of the largest non-venomous snakes in North America. It is identified by its heavy build, yellowish base color overlaid with large dark blotches, and a pointed, somewhat upturned snout adapted for burrowing. It is also known for producing a loud, hissing sound by vibrating a specialized structure near the airway, which it often pairs with tail vibration against dry leaves to mimic a rattlesnake.

Coloration & pattern

The base color ranges from pale yellow to tan or cream. Large, dark brown to black blotches run down the back, becoming more square and closely spaced toward the tail, while smaller alternating blotches appear along the sides. The pattern is bold and high-contrast, especially toward the front of the body, though it can appear more washed out in some populations.

Head, eyes & scales

The head is narrow and only slightly distinct from the neck, lacking the broad triangular shape of vipers. The snout is notably pointed and the rostral scale is enlarged and upturned, an adaptation for pushing through soil. Eyes are round-pupiled, consistent with its non-venomous, constricting nature. Body scales are keeled, giving a somewhat rough texture.

Size & body shape

Bull snakes are large and heavy-bodied, commonly reaching 4 to 6 feet, with some individuals exceeding 7 feet. The body is muscular and thick, tapering to a moderately long, tapering tail without any rattle segments.

Range & habitat where you'll see it

This snake is widespread across the central United States, from the Great Plains into the Rocky Mountain foothills, favoring open prairies, agricultural fields, sandy scrublands, and grasslands. It is a strong burrower and is often found in or near rodent burrows, which it also uses as a food source and shelter.

How to tell it apart from look-alikes

Bull snakes are most often confused with rattlesnakes due to their defensive hissing and tail-vibrating display. The key difference is the absence of a rattle, a narrow head without the broad triangular shape typical of pit vipers, and round rather than vertical pupils. Compared to other gopher snake subspecies, the bull snake tends to have a paler ground color and larger, bolder blotches. Its pointed snout, used for digging, is more pronounced than in most other similarly patterned colubrids in its range.