Eastern Foxsnake

Pantherophis vulpinus
Species of Conservation Concern
Other Common Name
Eastern Fox Snake
Family

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

Description

The eastern foxsnake, rare in Missouri, is a moderately large snake with distinct brown blotches. The ground color is gray, yellowish, greenish brown, or tan, with an average of 43 dark blotches on the back and sides with a brown to reddish-brown head. The belly is yellowish, marked with a prominent dark checkered pattern. When threatened, a foxsnake will vibrate its tail, coil with head and neck raised, and strike repeatedly to defend itself. When captured, foxsnakes give off a musky odor like the scent of a red fox, accounting for their name.

Young lack the yellow ground color and are gray with bold dark brown or black blotches. The head is boldly marked with a black mask running through the eyes and slanding back to the angle of the jaw. There are also black markings on top of the head and large black spots along the upper lips.

Hatchlings resemble western ratsnakes (black rat snakes). Counting ventral scales (belly scales, from neck to anus) is the best way to distinguish them (about 216 on foxsnakes, and about 221 on young western ratsnakes).

Similar species: The western foxsnake (P. ramspotti) is extremely similar to the eastern foxsnake. In Missouri, it is mainly identified by its different geographic distribution: the western foxsnake is restricted to a few counties in the northwestern corner of the state, while the eastern foxsnake occurs only in a few counties along the Mississippi River floodplain north from St. Louis. The western species has an average of 37 large brown blotches on the back and smaller ones on the sides.

Size

Length: 36 to 54 inches.

Habitat and conservation

This species mainly inhabits grasslands, scrub brush, and borders of woods; it also occurs along the edges of agricultural fields that adjoin wet prairies and marshes. Before European settlement, our two foxsnake species, combined, may have occurred across much of the northern half of Missouri; now they are restricted to our far northwestern corner and Mississippi River counties north of St. Louis.

Foods

Food includes small rodents, including mice and chipmunks, birds, and bird eggs. Foxsnakes kill their prey by constriction. Young foxsnakes eat frogs and insects.

Eastern Foxsnake dist map
Distribution in Missouri

Restricted to a few counties along the Mississippi River floodplain north from St. Louis.

Status

Critically imperiled in Missouri; a Species of Conservation Concern. Until recently, the foxsnakes in Missouri were all considered to be the "western" foxsnake, "P. vulpinus," comprising populations in both northeastern and northwestern Missouri. Now they have been divided into two different species. Our northwestern populations have retained the common name western foxsnake, but they have acquired a new scientific name, P. ramspotti. Meanwhile, P. vulpinus, in northeastern Missouri, has acquired the common name of eastern foxsnake.

Life cycle

Little is known of the life habits of foxsnakes in Missouri. Courtship and breeding apparently occurs in April, soon after emerging from overwintering dens. In June or July, the female lays 8–27 eggs in rotten stumps or logs, sawdust piles, or leaf litter. The eggs hatch in August or September. Hatchlings resemble western ratsnakes and are about a foot in length.

Human connections

This critically imperiled species is valuable as a controller of destructive rodents.

Ecosystem connections

As a predator, this snake helps keep populations of other animals, especially rodents, in check. Although it can defend itself by trying to bite, by vibrating its tail ominously, and by emitting a stinky smell when attacked, this snake often becomes food for hawks and other predators.