(by Jane Kolias)
Garter Snakes (Thamnophis sirtalis) are one of the most commonly seen snakes in NH. They hibernate in the winter below the frost line, sometimes in communal dens with other snake species. They emerge in the spring; and may even leave their dens when there is still snow on the ground.
Adult garter snakes average approximately 24” in length. These slender snakes are often darkish green in color with three vertical light stripes, one along the back and one on each side of their body, however their color can be variable. Their stripes may be shades of yellow, tan, blue, green or orange and their body may be olive, black, brown or gray. Their diet varies and may consists of earthworms, slugs, insects, other small snakes, salamanders, fish, and small mammals.
Garter snakes are ovoviviparous, meaning they give birth to live young. In NH, this happens between July and September. Newly born snakes may spend up to a few days around their mother but she does not provide parental care or protection after they are born.
Photo from sdherps.org.