Wild Guide

Eastern Gartersnake  | Thamnophis sirtalis

Status

Common

Size

18–26 inches

Distribution

Eastern half of the state

Eastern gartersnakes may be blackish, dark brown, greenish, or olive. Usually, they have three yellowish stripes — one down the back and one along each side — and the area in between may have alternating dark spots. Their bellies are yellowish green with two rows of faint black spots that are indistinct, somewhat hidden by the overlapping scales. A harmless snake, but when cornered, gartersnakes will bite to defend themselves.

Life Cycle

These daytime hunters are active from March through early November, but may be out during mild winters. Courtship and mating occurs in the spring, and females give birth to live young in late summer and early fall. A litter may contain four to 85 young, but averages about 12.

Foods

Eastern gartersnakes eat frogs, tadpoles, toads, salamanders, and earthworms. Occasionally they eat minnows, small mice, and small snakes of other species.
Human Connections
Fear and myth still surround snakes due to a lack of knowledge about them. However, people who know and understand gartersnakes have an appreciation for their contribution to outdoor Missouri.

Ecosystem Connections

As predators, gartersnakes keep populations of small animals in check. Although they can defend themselves by biting and smearing foul-smelling musk on attackers, they and their young provide food for many predators.

Did You Know?

Eastern gartersnakes favor areas near water, such as ponds, marshes, or swamps and damp woods or forested areas along creeks and rivers. They also live in empty lots and old abandoned farms. They are often found under boards, rocks, or other objects in city lots and near farm buildings. In winter, they take shelter in animal burrows or congregate in deep cracks in south-facing limestone bluffs or rocky hillsides.