Snake Identifier
Common Garter Snake

Common Garter Snake

Thamnophis sirtalisOrder: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: sirtalis

Widely distributed across North America, from subarctic regions of Canada to the Gulf Coast of Mexico and from the Atlantic to the Pacific coasts.

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Family

Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: sirtalis

Conservation

Least Concern (IUCN). They are one of the most common and widespread snake species in North America.

Physical Description

Slender body with keeled scales. Typically features a distinct dorsal stripe (cream, yellow, or greenish) and two lateral stripes on a background of dark olive, brown, or black. Checkered patterns are often visible between stripes.

Size & Dimensions

Specimen appears to be an adult of approximately 18-24 inches. Species typically ranges from 18 to 26 inches, with record lengths reaching 48 inches.

Habitat

Highly adaptable, found in meadows, marshes, woodlands, and hillsides, often near water sources. They are common in suburban gardens and parks at elevations from sea level to high mountains.

Diet & Feeding

Generalist carnivores that consume earthworms, amphibians, fish, slugs, and occasionally small rodents or birds. They use an active foraging strategy and hunt by scent and sight.

Reproduction

Ovoviviparous (gives birth to live young). Litters typically range from 10 to 40 young, born in late summer or early fall.

Look-alikes

Ribbon Snakes (Thamnophis saurita) which are more slender with stripes on scale rows 3 and 4, and various Water Snakes (Nerodia spp.) which lack the distinct longitudinal stripes.

Conservation Status

Least Concern (IUCN). They are one of the most common and widespread snake species in North America.

Cultural Significance

Ecologically vital as both predator and prey; they are frequently the first snake encountered by enthusiasts and help control garden pests like slugs and snails.

Notable Features

Noted for being one of the most cold-tolerant snake species, capable of being active in cooler temperatures that would render other reptiles dormant.

Identified on 7/1/2026