A Wandering Garter Snake is a sub-species of the Western Terrestrial Garter Snake. They can be found in high altitude areas from the Midwest prairies to the Pacific coast of North America. They eat frogs, tadpoles, fish, birds, mice, lizards, worms, grasshoppers, and small mammals. Wandering garter snakes tend to move further away from water than other garter snakes, giving them the “wandering” part of their name.