What to Know About the Eastern Garter Snake

Medically Reviewed by Vanesa Farmer, DVM on November 28, 2022
4 min read

Snakes are legless, slithering reptiles that can be found worldwide, except in Antarctica. There are more than 2,900 species of snakes, with 140 species known in the United States.

One species commonly found in the U.S. is the Thamnophis sirtalis, or the common garter snake, also known as the eastern garter snake. It’s a non-venomous snake native to North America.

With so many different snake species out there, it’s important to understand the physical and behavioral characteristics of the eastern garter snake. Understanding these characteristics can be beneficial to those who are planning to bring home a garter snake as a pet, but also for those who may encounter one in the wild and need to identify it. 

Appearance. The average eastern garter snake is around 18–26 inches long. Sometimes these snakes can grow to be around 49 inches. The most common way to tell garter snakes apart from other snakes is their color: they have dark bodies with three yellow stripes cascading down their backs. However, some have a checkered gray or red body with light-colored stripes.

Garter snakes have bellies that are creamy to yellow and green. 

Males exhibit thicker and longer tails than their female counterparts. However, females are generally longer than males.

Behavioral characteristics. Eastern garter snakes are solitary creatures, preferring to keep to themselves, but will congregate in times of brumation, a form of hibernation which allows snakes to wake up to drink water before returning to slumber. Garter snakes are known to be aggressive when threatened and will strike or bite. However, these snakes are generally considered harmless since they are non-venomous. As such, the eastern garter snake bite is harmless. 

Garter snakes are active throughout the day and night and may even be active on warm winter days. It’s common for garter snakes to birth more than 50 live babies at a time. 

Garter snakes are excellent swimmers and can even hunt for prey underwater. They like using debris such as logs and stones to bask on and then seek shelter when predators are nearby. 

While garter snakes are known to be harmless, they often produce a distinct odor when captured. It’s often compared to the odor a skunk releases when threatened. However, they’re easy to tame and are often kept as pets.

Habitat. In the wild, garter snakes can be found in various habitats. They’re most commonly found in North America, especially throughout the southeast. They favor moist, grassy environments and can be spotted in meadows, woodlands, hillsides, and marshes, and around bodies of water, such as those from ponds, ditches, lakes, and streams. 

While it’s common to find them near water sources, it’s not always the case, and they can travel long distances to suburban areas, where they’ll nest under debris, logs, rocks, boards, and vegetation. 

Because they help control pests, garter snakes are usually welcomed and respected by gardeners. 

Garter snakes are cunning escape artists. So, when keeping a garter snake as a pet, it’s important to make sure its enclosure is secure and that it cannot escape. The enclosure should contain dry and wet basking, resting, and soaking areas. The enclosure can be made from glass or suitable wood products and should have adequate ventilation. Providing them with ventilation will help keep their skin dry and free from skin diseases and illnesses. The enclosure should be kept from direct sunlight.

Include pools, branches, rocks, and other climbing structures for your garter snake. You should also include heaters, either under tank heating pads or heat tapes, and heat lights can work.

You can use various substrates in their enclosures, from unprinted newspapers, butcher paper, brown paper bags, paper towels, sterile sand, potting soil, and other types. Sawdust and high-dust shavings must be avoided as snakes can ingest these and end up with respiratory diseases. 

Avoid using pesticides anywhere near the outdoor habitat, and limit lawnmower usage and pet access as these can scare away garter snakes.

Diet. Garter snakes are carnivores and will eat anything they can easily overpower. Garter snakes hunt for their prey by sniffing them out with their long, forked tongues. They are active hunters. Eastern garter snake food consists of rodents, amphibians, birds, fish, and invertebrates.

Garter snakes are a common species throughout the United States, and most places have no conservation in place to protect these reptiles. Georgia is one state that protects the garter snake through conservation status.

In the wild, garter snakes are preyed upon by birds. Robins, specifically, eat garter snakes. Besides birds, garter snakes are threatened by overhunting, collecting, wanton killing, and destruction of their natural habitats. Additionally, they face a high mortality rate when trying to cross roads to find foraging habitats. 

One common disease noted in snakes, including garter snakes, is snake fungal disease (SFD). It’s caused by the Ophidiomyces ophiodilcola fungi. SFD has been found in places like Idaho and California.

The average eastern garter snake's lifespan is around 6-10 years in captivity. However, in the wild, their lifespan is shortened to around 2 years. Many wild garter snakes don’t live past their first year of life.