Bullsnake

Pituophis catenifer sayi

bull_snake.jpg

Image of a bullsnake
MDC Staff
Species of Conservation Concern
Other Common Name
Bull Snake
Family

Colubridae (nonvenomous snakes) in the order Squamata (lizards and snakes)

Description

The bullsnake is Missouri's largest snake. It is tan, yellow, or cream-colored with numerous, large, brown, or black blotches. The markings along the back and sides are generally black on the neck and tail, and brown at midbody. The tail may have light and dark bands. There is often a dark line angling from the eye down to the jaw, and black bars along the upper lip. The belly is yellow or cream-colored, with a checkering of square or rectangular, dark brown or black spots along the sides. If approached or cornered, a bullsnake will coil, vibrate its tail, and hiss loudly with the mouth partly open. If captured, it will bite to defend itself, but some individuals will calm down quickly and can be handled with ease.

Size

Length: 37 to 72 inches.

Bullsnake

Image of a bullsnake
Bullsnake hissing sound
Habitat and conservation

In Missouri, bullsnakes may be active from April through early November. They bask in the sun or search for food by day; at night they take shelter in mammal burrows, clumps of vegetation, in rock piles, or under objects. Commonly considered a prairie species, it also occurs in pastures, old fields, savannas, and along some river bluffs. It may also be found in open areas along the border of the Ozarks.

Foods

Small mammals, especially rodents, are the principal prey of this species. Known foods include mice, rats, ground squirrels, pocket gophers, small rabbits, and birds and bird's eggs. This species is extremely valuable in controlling destructive rodents. Bullsnakes kill their prey by constriction.

Bullsnake Distribution Map
Distribution in Missouri

Statewide, except for the southeastern third of the state. Most common along the western grassland areas of the state, with scattered locations throughout the Ozarks and northern Missouri.

Status

A Species of Conservation Concern.

Life cycle

Courtship and mating occur in April and early May. Eggs are laid during June or early July, with 3-22 eggs per clutch. Female bullsnakes deposit their eggs in sandy or loose soil, in abandoned small mammal burrows, or under large stumps or logs. The eggs adhere to each other after being laid. Hatching occurs in late August through September. The color of hatchlings is like that of adults, except their blotches are somewhat lighter.

Human connections

Because of the large number of crop-destroying rodents it eats, this species is a valuable neighbor to farmers. It is the most economically beneficial snake species in Missouri, and rural Missourians should make every effort to protect it.

Ecosystem connections

Bullsnakes rely on small mammals for food but many also take advantage of small mammal burrows for shelter and places to lay eggs. As with many other predatory species, bullsnakes can be preyed upon themselves by larger mammals and by birds. The eggs and young are especially vulnerable.