Common garter snakes come in a wide range of colors, including green, blue, yellow, gold, red, orange, brown, and black.

Garter snakes have a mild venom in their saliva, which may be toxic to the amphibians and other small animals that they prey upon.

Common garter snakes are resistant to naturally-occurring poisons in their prey, such as that of the American toad and rough-skinned newt, the latter of which can kill a human if ingested.

On the offensive side, the snake's venom can be toxic to some of its smaller prey, such as mice and other rodents.

Consuming the toxin can lead to reduced speed and sometimes no movement for extended periods of time, along with impaired thermoregulation.

[13] The habitat of the common garter snake ranges from forests, fields, and prairies to streams, wetlands, meadows, marshes, and ponds, and it is often found near water.

In warmer southern areas, the snake is active year-round; otherwise, it sleeps in common dens, sometimes in great numbers.

On warm winter afternoons, some snakes have been observed emerging from their hibernacula to bask in the sun.

Different biological factors such as body temperature and sex also influence whether the snake exhibits certain antipredatory behaviors.

[15][16] Garter snakes that exhibit more aggressive antipredatory displays tend to also be fast and have high stamina.

This is mostly due to aerobic energy production; pulmonary aeration increases up to three times in adult garter snakes when compared to juveniles.

In the early part of sex, when snakes are coming out of hibernation, the males generally emerge first to be ready when the females wake up.

[23] The diet of T. sirtalis consists mainly of amphibians and earthworms, but also leeches, slugs, snails, insects, crayfish,[24] fish, lizards, other snakes,[24] small birds, and rodents.

Common garter snakes are effective at catching fast-moving creatures such as fish and tadpoles.

Animals that prey on the common garter snake include large fish (such as bass and catfish), American bullfrogs, common snapping turtles, larger snakes, hawks, raccoons, foxes, wild turkeys, and domestic cats and dogs.

The common garter snake is considered to be a least-concern species by the IUCN Red List due to its wide distribution and high population size.

[1] Water contamination, urban expansion, and residential and industrial development are all threats to the common garter snake.