Plains garter snakes are long, striped garter snakes, usually from 40 to 70 cm long, but occasionally up to 109.5 cm. They have a dorsal and two lateral, yellow or orange stripes on a background scale color of dark brown to dark greenish. Lateral stripes are on scale rows 3 and 4. The sides may have some red pigmentation. Scales are keeled and measure 19 to 21 rows at the widest part of the body. There is a row of black spots between the lateral stripes and the scales on their belly. Males are slightly larger, with slightly longer tails. (Ernst and Ernst, 2003)
Plains garter snakes are found throughout the North American plains region, from the Oklahoma panhandle, northernmost Texas, and northeastern New Mexico north to southern Alberta, Saskatchewan, and Manitoba, and east through Minnesota, Wisconsin, and Indiana. (Ernst and Ernst, 2003)
Plains garter snakes are found in meadows, prairies, and other grasslands near sources of water, such as ponds, streams, marshes, and sloughs. They may also be found in swampy areas or along rivers. They may be found in suburban or urban vacant lots. Where they are found along with their close relative common garter snakes, they may be found in more dry habitats. This is because common garter snakes out-compete plains garter snakes for the more moist habitats. (Ernst and Ernst, 2003)
Plains garter snakes grow approximately 1.1 cm per week during their first year, after which growth slows. (Ernst and Ernst, 2003)
Males find females by using scent trails left by the females. Both males and females can mate with multiple individuals. (Ernst and Ernst, 2003)
Mating takes place after these snakes emerge from hibernation, in April or May. Plains garter snakes give birth to live young from June through September, after a gestation period of 83 to 102 days. There are from 5 to 60 young in a litter, but usually 10 to 20. (Ernst and Ernst, 2003)
Females give birth to live young. After the young are born, they do not need the help of either parent. (Ernst and Ernst, 2003)
A captive plains garter snake was recorded living to almost 8 1/2 years. (Ernst and Ernst, 2003)
Plains garter snakes are active from March to November, depending on the region. They may be active for shorter periods in northern portions of their range. They hibernate in burrows or rock crevices, although they may emerge on warm, winter days. They often hibernate in rodent burrows or ant mounts, but have also been found in crayfish burrows, under sidewalks, in other man made crevices, and even underwater. They are active during the day at warm temperatures, usually between 21 and 29 degrees Celsius. Once the air temperature goes above 31 degrees Celsius, these garter snakes switch their active period to night time. At much lower temperatures, prairie garter snakes become inactive. These snakes are solitary. (Ernst and Ernst, 2003)
Plains garter snakes stay within relatively small home ranges for long periods of time, moving only up to 76 meters over periods of over a year. (Ernst and Ernst, 2003)
Plains garter snakes use their sense of smell mostly. They find prey, mates, and hibernation sites by following scent trails. They also use vision and vibrations to help find their way around, avoid predators, and find prey. (Ernst and Ernst, 2003)
Plains garter snakes eat a wide variety of animal prey. The diet of plains garter snakes and common garter snakes is very similar, so they probably compete for prey where they are found in the same area. They eat frogs and toads, salamanders, fish, birds, small rodents, leeches, earthworms, and grasshoppers. Amphibians eaten include northern cricket frogs, American toads, great plains toads, tree frogs, striped chorus frogs, plains leopard frogs, northern leopard frogs, and various salamanders. They also eat mosquitofish, southern redbelly dace, bluntnose minnows, bank swallows, and eastern meadowlarks. Plains garter snakes find prey by following scent trails, then grabbing prey once they catch up with them. (Ernst and Ernst, 2003)
Plains garter snakes may be preyed on by birds of prey, such as red-shouldered hawks, Swainson's hawks, kestrels, and northern harriers. Other predators include foxes, coyotes, striped skunks, mink, domestic cats, and milk snakes. Humans also sometimes kill prairie garter snakes. These garter snakes will bite, emit a foul smell, or defecate to discourage predators. Their lateral stripes make them difficult to see in their grassy habitats and as they move. Plains garter snakes also have a series of antipredator displays that they will use, including hiding their heads, striking with the mouth closed or open, coiling or balling up their bodies, extending the body flat, and waving the tail. (Ernst and Ernst, 2003)
Plains garter snakes are important predators of amphibians, earthworms, leeches, and other animals in their prairie habitats. (Ernst and Ernst, 2003)
There are no adverse effects of plains garter snakes on humans. These are nonvenomous snakes that are shy and retiring, in general, although they will bite if threatened. (Ernst and Ernst, 2003)
Plains garter snakes are important members of the native prairie habitats they are found in.
Plains garter snakes are not considered threatened, although regional populations may be vulnerable. They are considered endangered in Ohio and a species of concern in Arkansas. (Ernst and Ernst, 2003)
George Hammond (editor), Animal Diversity Web Staff.
Tanya Dewey (author), University of Michigan-Ann Arbor.
living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.
an animal that mainly eats meat
uses smells or other chemicals to communicate
active at dawn and dusk
having markings, coloration, shapes, or other features that cause an animal to be camouflaged in its natural environment; being difficult to see or otherwise detect.
ranking system or pecking order among members of a long-term social group, where dominance status affects access to resources or mates
animals that have little or no ability to regulate their body temperature, body temperatures fluctuate with the temperature of their environment, often referred to as 'cold-blooded'.
the state that some animals enter during winter in which bodily functions slow down, reducing their energy requirements so that they can live through a season with little food.
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
an animal that mainly eats fish
light waves that are oriented in particular direction. For example, light reflected off of water has waves vibrating horizontally. Some animals, such as bees, can detect which way light is polarized and use that information. People cannot, unless they use special equipment.
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).
breeding is confined to a particular season
remains in the same area
reproduction that includes combining the genetic contribution of two individuals, a male and a female
living in residential areas on the outskirts of large cities or towns.
uses touch to communicate
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
Living on the ground.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
living in cities and large towns, landscapes dominated by human structures and activity.
movements of a hard surface that are produced by animals as signals to others
uses sight to communicate
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
Ernst, C., E. Ernst. 2003. Snakes of the United States and Canada. Washington, D.C.: Smithsonian Books.
Harding, J. 2000. Amphibians and Reptiles of the Great Lakes Region. Ann Arbor, Michigan: University of Michigan Press.