Almost everyone can identify a “garter snake” in Pennsylvania!
But here’s the problem:
There are multiple species and sub-species of garter snakes! Therefore, figuring out the identity of the SPECIFIC snake you are observing can be challenging. This is especially true since many of them have similar appearances and behaviors.
Today, you are going to learn about 3 garter snake species in Pennsylvania!
- *Just a quick note – to be officially considered a garter snake, the species must be in the genus Thamnophis*
#1. Eastern Garter Snake
- Thamnophis sirtalis sirtalis
- Adults typically range from 18 to 26 inches in length.
- Coloration varies and can be mixtures of green, brown, or black. Look for a distinct yellow or whitish stripe down the center of their back.
- Some individuals may exhibit a checkered body pattern.
- Subspecies of the Common Garter Snake.
Eastern Garter Snakes are common and easy to locate in Pennsylvania!
In fact, they are typically the snake species that people come across the most. They are well-adapted to living around people and can often be found in city parks, farmland, cemeteries, and suburban lawns and gardens. Though it’s not required, they prefer grassy environments near freshwater sources such as ponds, lakes, ditches, and streams.
Look for these garter snakes in Pennsylvania basking in the sun in grassy areas near cover.
Eastern Garter Snakes will protect themselves if they are cornered or feel threatened. For example, if you capture or continually disturb one, it will defecate and release a foul-smelling musk from glands. It’s also common for them to bite as a last resort!
The Eastern Garter Snake most commonly preys on toads, frogs, slugs, salamanders, fish, and worms. However, they are very opportunistic and will eat other insects and small animals they can overpower. They’re active during both the day and night, depending on the temperature.
These garter snakes have a high birth rate (up to 50 babies!) and adapt well to human-disturbed habitats! Because of these traits, this species is not threatened and is relatively common and widespread.
#2. Eastern Ribbon Snake
- Thamnophis saurita
- Adults typically range from 18 to 26 inches in length. A slender snake with a long tail!
- Coloration is brown to nearly black with three bright yellow to cream stripes; one down the back and one down each side.
- Snout and entire head are brownish, lips and underneath head are white.
Did you see a slender garter snake in eastern Pennsylvania with a long tail?
If so, it was probably an Eastern Ribbon Snake!
This species is semi-aquatic and RARELY found far from a source of water. Look for them in a wide variety of habitats, including marshes, grassy floodplains, streams, ditches with grass, wet areas in meadows, and woodlands adjacent to wetlands. Ribbon snakes are even found in suburban areas that match these conditions.
You might spot these snakes basking on branches of trees, bushes, or grasses overhanging the water. They typically hunt in the water and prey on amphibians, fish, and invertebrates.
If disturbed, these snakes will quickly flee into grass or brushy areas. If caught, they are not aggressive and rarely bite. But you can expect them to defecate and spray musk onto your hands. In the wild, Eastern Ribbon Snakes rely on blending into their surroundings to get away from predators.
#3. Short-headed Garter Snake
- Thamnophis brachystoma
- Adults range from 10 to 22 inches in length.
- Coloration is olive green with three beige to yellow stripes, one down the back and one down each side, bordered with small black spots.
- As the name suggests, there is no apparent distinction between the head and neck.
Short-headed Garter Snakes have a small range and population in western Pennsylvania. Look for them in fields or meadows by moving cover objects like rocks, logs, and other debris. However, you may also spot them basking or moving across the landscape in search of prey.
These small snakes feed almost exclusively on earthworms. However, in captivity, they have also eaten leeches, salamanders, frogs, and fish.
When handled, Short-headed Garter Snakes are relatively tame and rarely bite. However, if they feel threatened, you can expect them to release feces and musk into your hands!
Do you need additional help identifying garter snakes?
Try this field guide!
Which of these garter snakes have you seen in Pennsylvania?
Leave a comment below!