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Garter Snake

Scientific name: Thamnophis sirtalis

The garter snake is the most commonly seen snake in our area. It is small to medium in size and although it can bite; it is not poisonous to humans. Identifying one can be confusing as the coloration and patterns may differ and are not consistent. The image shows the most characteristic and common pattern. Note the three thin yellow stripes, one on each side and another on the top. The dark background color may be green, brown or black. Most confusing is when there is a checkerboard pattern of squares running between the stripes on each side! See the photo gallery below for some examples. The garter snake may be active in day or at night.

Females are larger than males. Still, they are rarely much longer than two feet, with the largest known of this species to reach 48 inches.

Learn more about all snakes found in New York  here.

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They eat a wide variety of insects, worms and even mice and small frogs.


One reason why they have been able to maintain their numbers is due to their adaptability. You might see one on your lawn, in your garden, field or even along a road. They like to live in stone walls, under piles of logs and other cool, damp spots. Like the turtle, they like to bask in a warm area, but also like to be able to make a quick escape if startled.

Life Cycle

They are viviparous, meaning that they give birth to live young. After brumation, the males will emerge first, followed by the females. The female releases a pheromone which is very powerful and attracts many males all at the same time. The resulting scene (which you can Google) is called a “mating ball”.  The female can store sperm for a very long time, if she needs to. The fertilized eggs incubate and hatch inside the female. They are then born, ready to hunt and fend for themselves.

Ecosystem Connections

Many animals such as hawks, possums, and raccoons will eat the garter snake.

Fun Facts

In winter they brumate (a lethargic state similar to hibernating). They often pick spots like piles of rocks or boulders, or even in the craggy foundations of houses. They may brumate with just a few friends or with hundreds of others. Snakes of different species will brumate together.

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