Common Garter Snake
Thamnophis sirtalis • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: T. sirtalis
North America, extending from southern Canada through the United States to parts of northeastern Mexico, spanning coast to coast across diverse regions.
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, as the species is widespread, highly adaptable, and maintains stable populations across most of its range.
Physical Description
Dark body coloration with characteristic longitudinal light-colored stripes. The head features distinct vertical dark bars along the labial scales, prominent eyes with round pupils, and keeled dorsal scales giving a textured appearance.
Size & Dimensions
Specimen size in photo is obscured, but adults typically range from 46 to 137 cm (18 to 54 inches) in total length, with females generally larger than males.
Habitat
Highly adaptable, found near water sources such as marshes, streams, and ponds, as well as in meadows, woodlands, agricultural fields, and suburban backyards.
Diet & Feeding
Diet consists of amphibians, earthworms, small fish, slugs, and occasionally small rodents or birds. They actively forage using both sight and chemoreception (tongue-flicking).
Reproduction
Ovoviviparous, giving birth to live young. Mating typically occurs in the spring shortly after emerging from brumation, resulting in litters that can range from 10 to over 80 offspring.
Conservation Status
IUCN Red List status is Least Concern, as the species is widespread, highly adaptable, and maintains stable populations across most of its range.
Cultural Significance
Commonly encountered in suburban areas, often serving as a beneficial garden predator that helps control pest populations like slugs and insects. Popular in educational settings and as pets due to adaptability.
Notable Features
Features distinct vertical black bars on the lip scales (labials), which is a key diagnostic feature for separating this species from many other similar snakes.