Thamnophis sauritusEastern Ribbonsnake

Geographic Range

Eastern ribbon snakes are found throughout much of eastern North America east of the Mississippi River. They occur from southern Maine, across southern Ontario, throughout Michigan, south to eastern Louisiana, throughout the Gulf states, including Florida, and throughout the eastern seaboard. They appear to be largely absent from southern Ohio, southeastern Illinois, central Pennsylvania, West Virginia, Kentucky, Tennessee, and northern Alabama and Georgia. There are isolated populations in parts of Kentucky and Wisconsin. (Harding, 2000)


Eastern ribbon snakes prefer wet meadows and fields, especially near the edges of lakes, ponds, streams, and marshes. They are most often found in open, sunny sites. (Harding, 2000)

  • Aquatic Biomes
  • lakes and ponds
  • rivers and streams

Physical Description

Eastern ribbon snakes are slim, striped snakes with long tails relative to their body length. They have three white, yellow, or greenish stripes that run along the length of their body on a background color of black or dark brown. This striped pattern makes them difficult to see in the grassy habitats they prefer. The head is wider than the neck and their relatively large eyes are bordered by a light bar in front. Their belly is white, yellow, or green without blotches. The scales above their mouth are bright white or yellow, without dark borders (as in garter snakes). Their scales are keeled (with a raised ridge along their length). Females are slightly larger than males and total body length ranges from 46 to 86.2 cm. Young eastern ribbon snakes are born alive and are from 16 to 24 cm long. (Harding, 2000)

  • Sexual Dimorphism
  • female larger
  • Range length
    46.0 to 86.2 cm
    18.11 to 33.94 in


Mating typically occurs when snakes emerge from hibernation. Males seek out females and attempt to mate with them. (Harding, 2000)

Mating takes place soon after these snakes have emerged from hibernation in the spring, they also sometimes mate in the fall. Live young are born in late summer, litter size ranges from 4 to 27 young, with 12 being average. Young snakes grow rapidly and often become mature before their second year, though some females don't breed until their third year. (Harding, 2000)

  • Breeding interval
    Eastern ribbon snakes breed once or twice yearly.
  • Breeding season
    Young are born in late summer, typically.
  • Range number of offspring
    4.0 to 27.0
  • Average number of offspring
  • Average number of offspring
  • Range age at sexual or reproductive maturity (female)
    1.0 to 3.0 years
  • Range age at sexual or reproductive maturity (male)
    1.0 to 3.0 years

The young are nurtured inside of their mother's body until they are born. Once they are born there is no further parental care. (Harding, 2000)

  • Parental Investment
  • pre-fertilization
    • provisioning
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female


Little is known of eastern ribbon snake lifespan in the wild, they probably live for several years, once they have survived their first year. (Harding, 2000)

  • Average lifespan
    Status: captivity
    10.6 years


Eastern ribbon snakes are active and fast-moving snakes. They are usually seen at or near the edge of a body of water, but may also be found in moist meadows away from water. They bask on logs and rocks but also climb into bushes to bask. They are active from April to October and hibernate through the winter in the abandoned burrows of animals such as rodents and crayfish, or in anthills. These snakes are most active during the day and are mainly solitary, though they may share hibernation sites with other snakes. (Harding, 2000)

Communication and Perception

Eastern ribbon snakes communicate with each other primarily through touch and smell. They use their forked tongues to collect chemicals from the air and insert these forks into a special organ in the roof of their mouth, which interprets these chemical signals. Snakes are also sensitive to vibrations and have reasonably good vision.

Food Habits

Eastern ribbon snakes eat mainly frogs, salamanders, and their larvae. They will also eat small fish, but rarely eat earthworms. They capture prey by stalking or chasing them. (Harding, 2000)

  • Primary Diet
  • carnivore
    • eats terrestrial vertebrates
  • Animal Foods
  • amphibians
  • fish
  • terrestrial worms


Eastern ribbon snakes are eaten by many of the predators that frequent the habitats in which they are found. This includes great blue herons, hawks, mink, and raccoons. Young snakes are vulnerable to large fish and large frogs. They escape predation by being fast and agile, they will readily flee into the water, where they may dive to hide below the surface, or into dense vegetation. When harassed, eastern ribbon snakes will flatten their heads and bite at the attacker. They will also thrash their bodies violently and smear the attacker with a foul-smelling secretion. (Harding, 2000)

Ecosystem Roles

Economic Importance for Humans: Positive

Eastern ribbon snakes may occasionally eat common garden pests, such as slugs and insect larvae. (Harding, 2000; Harding, 2000)

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

There are no negative effects of eastern ribbon snakes on humans. (Harding, 2000)

Conservation Status

While eastern ribbon snakes are not currently recognized as threatened, the habitats they prefer are continually threatened by development and contamination. It is important to continue to monitor populations. (Harding, 2000)

Other Comments

There are four subspecies of Thamnophis sauritus: northern ribbon snakes (T. s. septentrionalis, occurring from southern Maine through southern Ontario, Michigan, and northern Ohio and Indiana, with some isolated populations in Wisconsin, eastern ribbon snakes (T. s. sauritus), occurring throughout the eastern seaboard states to the Gulf of Mexico and north along the eastern shores of the Mississippi River, peninsula ribbon snakes (T. s. sackenii), in Florida and southern Georgia, and bluestripe ribbon snakes (T. s. nitae), found only along the Gulf coast of northwestern peninsular Florida. (Conant and Collins, 1991)


Tanya Dewey (author), Animal Diversity Web.



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.

World Map


uses sound to communicate


living in landscapes dominated by human agriculture.


an animal that mainly eats meat


uses smells or other chemicals to communicate

  1. active during the day, 2. lasting for one day.

union of egg and spermatozoan


having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.


the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.


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).


marshes are wetland areas often dominated by grasses and reeds.

native range

the area in which the animal is naturally found, the region in which it is endemic.


reproduction in which eggs develop within the maternal body without additional nourishment from the parent and hatch within the parent or immediately after laying.


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).

seasonal breeding

breeding is confined to a particular season


reproduction that includes combining the genetic contribution of two individuals, a male and a female


lives alone


living in residential areas on the outskirts of large cities or towns.


a wetland area that may be permanently or intermittently covered in water, often dominated by woody vegetation.


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.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.


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.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.


movements of a hard surface that are produced by animals as signals to others


uses sight to communicate


Conant, R., J. Collins. 1991. Reptiles and Amphibians of Eastern/Central North America, 3rd edition. New York: Houghton Mifflin Company.

Harding, J. 2000. Amphibians and Reptiles of the Great Lakes Region. Ann Arbor, Michigan: University of Michigan Press.