Common Garter Snake
Thamnophis sirtalis • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: sirtalis
Widely distributed throughout North America, ranging from the subarctic regions of Canada through most of the United States to northern Mexico.
Look up Common Garter Snake in the Snake Encyclopedia →Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Thamnophis, Species: sirtalis
Conservation
Least Concern (IUCN); very common and adaptable, though threatened locally by habitat loss and pesticide use.
Physical Description
The shed skin shown reveals keeled (ridged) scales and a pattern indicating longitudinal stripes or checkered spots. Live specimens typically have three yellow or greenish stripes and a slender body with round pupils.
Size & Dimensions
The shed shown appears to be approximately 18-24 inches. Adults typically range from 18 to 26 inches (46 to 66 cm), with a maximum recorded length of 54 inches.
Habitat
Generalist species found in forests, grasslands, fields, and suburban backyards, usually in close proximity to water sources like marshes, lakes, or streams.
Diet & Feeding
Feeds primarily on amphibians (frogs, toads, salamanders), earthworms, and small fish using active foraging and swallowing prey alive.
Reproduction
Ovoviviparous (gives birth to live young); typical litter sizes range from 10 to 40 neonates born in late summer.
Conservation Status
Least Concern (IUCN); very common and adaptable, though threatened locally by habitat loss and pesticide use.
Cultural Significance
One of the most recognizable snakes in North America; ecologically important for controlling pest populations and serves as food for many birds of prey.
Notable Features
Highly cold-tolerant; known for 'brumation' in large communal dens where hundreds of snakes may congregate during winter.