Common Garter Snake

(Thamnophis sirtalis)

NH Conservation Status: Not listed

State Rank Status: Widespread and secure

Distribution: Throughout NH

Description: A small striped snake measuring 18-26 inches. Has variable color patterns but typically has 2-3 yellow, brownish, or greenish stripes running vertically down the top and sides of the snake. May also have variable black spots between the stripes.

Commonly Confused Species: Eastern ribbon snake; Brown snake

Habitat: Found in a variety of habitats including woodlands, hillsides, wetlands, backyards, and even urban areas. Will use a variety of cover objects for shelter including rocks, logs, stumps and other debris such as trash piles and sheet metal.

Life History: Breeding may occur in spring or fall. Ten to 40 live young are born from July to September. Hibernation may be solitary or communal in rock crevices, holes, stumps, or foundations.

Conservation Threats: Species is secure

Distribution map: Click here for a map showing the towns where this species is reported to occur in NH

Garter snakes can vary greatly in appearance but they generally have a dark body with yellow stripes or blotches. Photo by Mike Marchand.	The lower jaw, chin, and belly of a garter snake are light yellow. Photo by Mike Marchand.
Garter snakes vary in coloration and pattern, sometimes lacking obvious stripes. Photo by Keegan Uhl.	This young garter snake has some white and blue flecks. Photo by Mike Marchand.
The cloudy eye of this garter snake indicates that it will soon be shedding the outer layer of its skin. Photo by Mike Marchand.	This garter snake is missing the end of its tail, perhaps a result of an encounter with a predator. Photo by Mike Marchand.
Melanistic (black) garter snake observed in northern New Hampshire. This snake has keeled scales (a ridge/line down the center of each scale); a black racer would have smooth scales (no ridge/line). (Photo by John Darak)