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Common Garter Snake

(Thamnophis sirtalis)

Picture of a common garter snake

Area where common garter snake is found in South Dakota


  • Known to many people as the red-sided garter snake
  • Bright yellow or orange stripe along the middle of back
  • Yellow or orange stripe on each side of body on scale rows 2 and 3 (counting from belly scales up)
  • Black spots on a reddish background along body sides
  • Keeled scales
  • Nonvenomous
  • Diet: frogs and other aquatic vertebrates, insects, earthworms, and small mammals
  • Habitat: grassy areas near wetlands
  • Distribution: statewide