Back to Education Index

This page is about Garter Snakes (Of the Genus Thamnophis)

  • The name Garter Snake is the common name given to a group of harmless, small- to medium-sized snakes belonging to the genus Thamnophis. Endemic to North America, they can be found from the Sub Arctic plains of Canada to Central America. At present there are around 40 Different species and subspecies of Garter Snake recognised.
  • Garter Snakes are present throughout almost all of North America. They have a large distribution due to their varied diets and adaptability to different habitats, with varying proximity to water; however, in the western part of North America, these snakes are more aquatic than in the eastern portion. Garter snakes populate a wide variety of habitats, including forests, woodlands, fields, grasslands, and lawns. They predominantly inhabit areas with some form of water, usually with an adjacent wetland, stream, or pond. This reflects that amphibians make up a large part of their diet.
  • Garter snakes, like all snakes, are carnivorous. Their diets is as wide ranging as their choice of habitat consisting of almost any creature they are capable of overpowering including slugs, earthworms, leeches, lizards, amphibians, ants, crickets, frog eggs, toads, minnows, and rodents. When living near water, they will eat other aquatic animals. The ribbon snake (Thamnophis sauritus) in particular favours frogs (including tadpoles), readily eating them despite their strong chemical defences. Food is swallowed whole. Garter snakes adapt to eating whatever they can find, and whenever, because food can be scarce at times throughout the year. Although they feed mostly upon live animals, they will sometimes eat eggs.
  • Garter snakes have a complex system of pheromone based communication. They can find other snakes by following their pheromone-scented trails. Male and female skin pheromones are so different as to be immediately distinguishable. However, male garter snakes sometimes produce both male and female pheromones. During mating season, this ability fools other males into attempting to mate with them. This causes the transfer of heat to them in kleptothermy, which is an advantage immediately after hibernation, allowing them to become more active.
  • If disturbed, a garter snake may coil and strike, but typically it will hide its head and flail its tail. These snakes will also discharge a malodorous, musky-scented secretion from a gland near the cloaca.
  • Garter snakes were long thought to be nonvenomous, but recent discoveries have revealed they do, in fact, produce a mild neurotoxic venom and although they cannot kill humans with the small amounts of comparatively mild venom they produce, they also lack an effective means of delivering it.

    Click HERE for a Garter Snake care sheet.