Common Garter Snake
Thamnophis sirtalis • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: T. sirtalis
Widely distributed throughout North America, ranging from southern Canada down through much of the United States to parts 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
Listed as Least Concern on the IUCN Red List due to its broad distribution, high adaptability, and large population numbers.
Physical Description
Slender body with longitudinal light stripes running down a darker background, checkered patterns visible between stripes, keeled dorsal scales, and a distinct head shape slightly wider than the neck.
Size & Dimensions
Estimated specimen length is approximately 45 to 60 cm. Adult typically ranges from 46 to 137 cm in total length.
Habitat
Found in a diverse range of habitats including meadows, marshes, woodlands, and along the edges of streams and ponds, often near permanent or temporary water sources.
Diet & Feeding
Diet consists primarily of amphibians (frogs, toads, salamanders), earthworms, small fish, and occasionally small mammals or birds. Active forager using keen eyesight and a sensitive tongue to detect prey.
Reproduction
Viviparous (live-bearing), giving birth to litters typically ranging from 10 to 40 or more young in late summer after mating in the spring.
Look-alikes
Can be confused with other garter snake species (Thamnophis spp.) and ribbon snakes (Thamnophis saurita), distinguished by specific scale counts, stripe placement, and head markings.
Conservation Status
Listed as Least Concern on the IUCN Red List due to its broad distribution, high adaptability, and large population numbers.
Cultural Significance
Frequently encountered by humans in suburban and rural gardens, serving an important role in controlling invertebrate and amphibian populations.
Notable Features
Known for high tolerance to lower temperatures compared to many other reptiles, and possesses well-developed chemical sensory tracking abilities.