Common Garter Snake
Thamnophis sirtalis • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: T. sirtalis
Widely distributed across North America, ranging from the Atlantic to the Pacific coast, spanning from southern Canada down through much of the United States to the Gulf of Mexico.
Look up Common Garter Snake in the Snake Encyclopedia →Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: T. sirtalis
Conservation
IUCN Red List status is Least Concern, due to its exceptionally wide distribution, adaptability to various habitats, and generally large and stable populations.
Physical Description
Characterized by prominent longitudinal light stripes running down the body (one vertebral stripe and two lateral stripes), a dark base coloration (blackish or dark brown), and checkered patterns between the stripes. The scales are keeled, and the head is moderately distinct from the neck with round pupils.
Size & Dimensions
The pictured specimen appears to be a subadult or small adult, measuring roughly 45 to 60 cm. Typical adults range from 46 to 137 cm in total length.
Habitat
Highly adaptable, found in diverse habitats including meadows, marshes, woodlands, and close to permanent or temporary bodies of water such as ponds, lakes, and streams. Prefers areas with ample cover and damp substrates.
Diet & Feeding
Diet is opportunistic and varied, consisting largely of amphibians (frogs, toads, salamanders), earthworms, small fish, and occasionally small mammals or birds. Actively forages using keen chemical senses.
Reproduction
Viviparous (live-bearing), giving birth to litters typically ranging from 10 to 40 or more young. Mating occurs primarily in the spring shortly after emerging from brumation, sometimes involving large communal mating balls.
Look-alikes
Frequently confused with other garter snake species (such as the Ribbon Snake, Thamnophis saurita) and lined snakes (Tropidoclonion lineatum). Distinguished by the specific placement of the lateral stripes on the second and third scale rows.
Conservation Status
IUCN Red List status is Least Concern, due to its exceptionally wide distribution, adaptability to various habitats, and generally large and stable populations.
Cultural Significance
Often featured in educational programs and nature centers due to its gentle nature when handled and widespread familiarity. Plays an important ecological role in controlling amphibian and invertebrate populations.
Notable Features
Exhibits complex chemical communication systems, relies heavily on pheromones for tracking prey and finding mates, and can form massive communal dens during winter brumation.