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Garter / Ribbon snake

Plains Garter Snake

Harmless

Thamnophis radix

Plains Garter Snake
Thamnophis radix, © Jeff Birek
Plains Garter SnakePlains Garter SnakePlains Garter SnakePlains Garter SnakePlains Garter Snake

6 photographs of the Plains Garter Snake. © Jeff Birek.

The Plains Garter Snake (Thamnophis radix) is a non-venomous snake in the Colubridae family, recorded in 2 countries.

Also called
Garter / Ribbon snake
Family
Colubridae
Size
Slender, 1.5–3 ft.
Habitat
Almost anywhere with moisture — gardens, fields, wetlands, and streamsides.
Behavior
Harmless and active by day; may release musk if handled. The most commonly seen snakes across most of the U.S.
Identify
Slender body with three light stripes running the length of a darker back.

About the Plains Garter Snake

The plains garter snake (Thamnophis radix) is a species of garter snake native to most of the central United States as far north as Canada and as far south as Texas. It has a distinctive orange or yellow stripe from its head to tail, and the rest of its body is mainly a gray-green color. The snake is commonly found living near water sources such as streams and ponds, but can also be found in urban areas and vacant lots. Although the IUCN lists the species as "Least Concern", some states have given it their own special status. This species is mildly venomous, although the venom is not toxic to humans.

Description

Physical

The plains garter snake has either an orange or yellow stripe down its back and distinctive black bars on its lip. The stripe normally starts at the head and continues all the way to the tail tip. Lateral stripes are located on the third and fourth scale rows and are normally a greenish-yellow color. Its belly is gray-green with small dark spots along the edges. Most have distinctive light yellow spots on the top of the head. The snake is described as medium-sized and is on average around 3 ft (0.91 m).

Behavior

Described as "one of the most cold-tolerant snakes", on warmer winter days, it often comes out of hibernation to bask in the sun. It is most active between April and late October depending on location. Mating normally takes place in April or May and birth takes place between August and October. Courtship usually occurs near the communal hibernation site, and polygynous mating systems have been observed. The snake's typical diet consists of earthworms, slugs, and small amphibians, including the larvae of salamanders. It has also been observed eating small mammals and birds, such as bank swallows and eastern meadowlarks.

Habitat

The plains garter snake is commonly found in meadows and prairies adjacent to water sources, such as marshes, streams, and ponds. In built-up areas of the Chicago area, it has been observed in abandoned buildings, trash heaps, and vacant lots. Populations in urban and suburban areas have been greatly reduced due to building activities and pesticide use. Its habitat range overlaps with that of the common garter snake (Thamnophis sirtalis) in many areas, and it is thought the two species may hybridize.

Geographic range

The snake ranges across a broad area of North America from as far north as central Alberta to as far south as Northern Texas and New Mexico. In the United States, it is also found in Iowa, eastern Wyoming, northern Kentucky, eastern Colorado, Minnesota, southern Wisconsin, Illinois, northwestern Indiana, Oklahoma, Nebraska and the northern half of Missouri. A small population is also in Ohio. In Canada, the species is also found in Manitoba. It can be found at elevations from 400 to 7,500 feet, but prefers to stay under 6,000 feet.

Subspecies

Adapted from Wikipedia, available under CC BY-SA.

Frequently asked: Plains Garter Snake

Is the Plains Garter Snake venomous?
No. The Plains Garter Snake (Thamnophis radix) is non-venomous and is not considered dangerous to humans. Like most snakes, it will retreat rather than bite when given the chance.
Is the Plains Garter Snake poisonous?
Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Plains Garter Snake is neither poisonous nor venomous.
Is the Plains Garter Snake dangerous?
The Plains Garter Snake is not dangerous to humans. It has no medically significant venom and bites only defensively if cornered or handled.
Where does the Plains Garter Snake live?
The Plains Garter Snake has verified records in 2 countries, including United States of America, Canada. See the distribution section below for its full range.
How do I identify the Plains Garter Snake?
Slender body with three light stripes running the length of a darker back.
How big does the Plains Garter Snake get?
Slender, 1.5–3 ft.

Where it is found

More Colubridae snakes

Classification

How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.

OrderThe broad group of scaled reptiles: all snakes and lizards
Squamata
FamilyA group of related snakes that share key traits
Colubridae
GenusA close-knit group of very similar species
Thamnophis
SpeciesThis exact snake, named in the two-part scientific name
Thamnophis radix

Keep learning

Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.