Facts, Identification & Control

Scientific Name

Thamnophis sirtalis


What Do They Look Like?

  • Size: The snake’s average length is 18-26 inches, but can grow up to four feet long.
  • Characteristics: The common garter snake is long and slender with a colorful and extremely variable appearance.
  • Coloring: Its upper body can range from black, brown-grey, olive, or red. There are normally three light stripes running along its length. These stripes can vary from yellowish to brown, green, blue, orange, gray, or whitish, and are normally well defined, although they may occasionally be indistinct or even absent. The under parts of the common garter snake are usually cream or white.

How Did I Get Common Eastern Garter Snakes?

The pests are one of the most abundant snakes in the country, and they can survive in many habitats. Homeowners find common eastern garter snakes under debris, in wood piles, and swimming around ditches or ponds. Yards with tall grass and ground debris, woodlands, grasslands, and gardens that are near a water source are prime places for these snakes to hunt and live.

Garter snakes are predators that consume many small prey. On rare occasions, common eastern garter snakes move indoors. These pests spend the winter in communal dens anywhere sheltered and warm, including under homes. From here, the snakes may accidentally wander inside.

How Serious Are Common Eastern Garter Snakes?

Will They Bite?
Just like any snake, a common eastern garter snake will strike in self-defense. However, the pests’ tiny teeth can do little more than scratch the skin. Although they are not considered venomous, they have a gland above the upper jaw on either side of the mouth (corresponding to the venom gland of vipers and other venomous snakes) that produces a mildly toxic venom.

Are They Dangerous?
In general, bites from garter snakes are harmless because these snakes lack fangs and thus cannot efficiently inject secretions. However, prolonged bites by western terrestrial and common garter snakes have caused swelling and localized bleeding in people, presumably because unusually large amounts of venom seep into the bite. Their presence may startle those who come across them while doing yard work or accessing crawl spaces.

How Do I Get Rid of Common Eastern Garter Snakes

What You Can Do
Some common techniques to help avoid these pests include:

  • Reduce Attractants: Eliminating or reducing their food supply and cover can discourage common garter snakes.
  • Landscaping: Mow closely around homes and outbuildings, store firewood and lumber away from residences, and reduce piles of rocks, leaves, or other items that give snakes shelter.
  • Seal Entries: Seal cracks and crevices in buildings and around pipes and utility connections.
  • Fencing: Small areas where children might play can be protected from most snakes with a snake-proof fence.
  • Repellents: Use of ultrasonic sound emitters (snakes can’t hear, at least in high frequencies) or fake owls or hawk decoys do not work to repel garter snakes.

What Wildlife Removal Companies Do
Local wildlife removal companies like Critter Control and Trutech Wildlife Service train their technicians to help manage common eastern garter snakes and similar pests. Since every building or home is different, the wildlife control technician will design a unique program for your situation.

Trutech and Critter Control can provide the right solution to keep common eastern garter snakes in their place…out of your home, or business.

Behavior, Diet, & Habits

Common garter snakes are one of the first snakes to appear in spring and can be seen throughout the year, even on very warm winter days. They are excellent swimmers and frequently hunt by swimming slowly along the margins of pools, often sweeping their open mouth from side to side and seizing its prey. It may also track prey on land by scent and by sight, or catch earthworms by locating and thrusting its snout into the worm tunnel below the soil level.

What Do They Eat?
Earthworms and amphibians often make up the majority of the garter snake diet. Large adults can also prey on immature voles or mice. The common garter snake takes a diverse range of prey, including:

  • Crayfish
  • Earthworms
  • Fish
  • Insects
  • Leeches
  • Salamanders
  • Slugs
  • Small Toads
  • Spiders
  • Tadpoles

Geographic Range
Common garter snakes are found from the Atlantic to the Pacific coast, except for the dry deserts in the southwest.

Where Do They Live?
They are particularly fond of moist, grassy environments close to water that can be found in a wide variety of habitats, including:

  • Hillsides
  • Marshes
  • Meadows
  • Woodlands

They are among the most commonly encountered snakes in suburban areas, provided there are protective locations nearby such as:

  • Debris piles
  • Logs
  • Rocks
  • Vegetation

Unlike other snakes, garter snakes do not lay eggs. Instead, they give live birth to up to 50 young.