Terrestrial Garter Snake
This is the only garter snake species with a well-documented tendency to constrict prey, although the constriction is inefficient when compared with the constriction of many other snakes.
About This Species
The terrestrial garter snake is an immensely variable species, and even the most experienced herpetologists have trouble with its identification and it is often is mistaken for the blackneck garter snake, common garter snake, and checkered garter snake (Thamnophis marcianus, not known to inhabit Colorado). Like all garter snakes, they are mildly venomous, but are not considered dangerous to humans.
More Information:
Physical Characteristics
Pale (but not white) stripes on sides of body on second and third scale rows above outer edges of belly scales; light stripe down middle of back bright, dull, incomplete, or virtually absent; often two large black marks on neck; irregular black marks frequently on belly; usually eight upper lip scales on each side of head; narrow dark marks (if any) on upper lips confined to front edge of vertical suture between lip scales; upper scales keeled; anal scale usually single; typically 21 rows of scales on back and sides at midbody; in Colorado, few individuals exceed 30 inches (76 cm) total length.
Range
Throughout most of Colorado, excluding most of the plains region in the northeastern quarter of the state, usually at elevations below 11,000 feet but has been found higher. Common.
Habitat
Almost any terrestrial or wetland habitat in the vicinity of virtually any flowing or non-flowing body of water; not restricted to riparian-aquatic environments, frequently occupies terrestrial habitats far from water. Activity takes place on the ground, in water, or in low vegetation.
Diet
The diet is highly variable and includes worms, slugs, snails, grasshoppers, fishes, amphibians, lizards, snakes, birds, and small mammals obtained on land or in the water.
Reproduction
Females give birth to their young usually in July in lowland areas of southern Colorado but not until August or September in the mountains.