Reliable figures don’t generally exist for animals that aren’t endangered, but it’s probably the common garter snake (Thamnophis sirtalis).
Garter snakes are members of the Colubridae, which is the largest family of snakes and contains almost 2,000 species and several dozen of these are species of garter snake.
The common garter snake is found right across North America and is the only snake species native to Alaska. They are very thin – no thicker than your thumb – but can be over a metre (3.2 feet) long.
They have a mildly venomous bite, but it doesn’t cause anything worse than an itchy swelling in humans.
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