Other common names
Eastern gartersnake, Blue-striped gartersnake, Gartersnake, Garter snake, Garter
Most adult common gartersnakes are about 18-26 inches (46-66 cm) in total length. These are slender snakes with three thin light-colored stripes running the length of the body. Adults have a background color of black, greenish brown, tan, or gray with one stripe running down the middle of the back and one stripe running along each side. The stripes are typically yellow, green, brown, blue, or white. However, some individuals may lack stripes. A dark checkerboard pattern may be visible along the sides of the body between the back and side stripes. The eyes are large and prominent. The coloration of juveniles is similar to adults.
Range in Florida
Common gartersnakes are found throughout mainland Florida in every county, and there is one record from the Florida Keys.
Assessment of risk to people and pets
Non-venomous. Common gartersnakes are not dangerous to people or pets, but they will readily bite to defend themselves. These snakes are not aggressive and avoid direct contact with people and pets. Virtually all bites occur when the snakes are intentionally molested.
Comparison with other species
Eastern ribbonsnake (Thamnophis saurita)
Most adult common gartersnakes are about 18-26 inches (46-66 cm) in total length, with a record length of 54 inches (137.2 cm). These are slender snakes with three thin light-colored stripes running the length of the body. The color pattern on the body can be highly variable. Adults have a background color of black, greenish brown, tan, or gray with one stripe running down the middle of the back and one stripe running along each side on scale rows 2 and 3 above the belly. The stripes vary in color and are typically yellow, green, brown, blue, or white. However, stripes are absent in some individuals. A dark checkerboard pattern may be visible along the sides of the body between the back and side stripes. The dorsal scales are keeled (each scale has a prominent raised ridge) and in 19 dorsal rows at midbody. The belly is uniform whitish-green or whitish-blue and without any markings. The head is only slightly distinct from the neck. The upper lip scales are light-colored and have thin black lines along their vertical edges making them look like teeth. The eyes are large and prominent, and the pupil is round. The tongue is bright red with a black tip. The coloration of juveniles is similar to that described for adults.
Common gartersnakes can be found in pinelands, hardwood hammocks, cypress strands, prairies, marshes, melaleuca stands, and any wet grassy habitats, especially along the edges of any standing or flowing bodies of water. Adults and juveniles of this species are often found in suburban neighborhoods where development encroaches into favorable habitats.
When approached, gartersnakes will typically flee for shelter, relying on speed and agility to avoid capture. However, if they are cornered, both juveniles and adults will strike at the attacker and rapidly vibrate the tip of the tail, which produces a buzzing sound in leaf litter. If grabbed or pinned, they will readily bite the attacker and release a foul-smelling musk from a pair of glands in the base of the tail. Nonetheless, these snakes are not aggressive, and striking is only used in defense as a last resort.
Common gartersnakes are typically diurnal (active during the day) and feed mostly on frogs, salamanders, freshwater fishes, and earthworms. However, these snakes are also known to eat slugs, snails, leeches, small mammals, young birds and eggs, small snakes, and various arthropods. Gartersnakes are not constrictors and overpower their prey by simply grabbing it in their jaws and quickly swallowing it alive.
In Florida, females give live birth to 3-80 young between July and October.
- Blue-striped gartersnake (Thamnophis sirtalis similis) Blue-striped gartersnakes primarily occur in Florida along the Gulf coast from eastern Wakulla County in the panhandle south to Hernando County in the central peninsula. However, individuals are occasionally found outside of that main Gulf-coast area, including well into Georgia. It is not understood why individuals in this area are blue!
- Eastern gartersnake (Thamnophis sirtalis sirtalis) Eastern gartersnakes are found throughout most of mainland Florida, with the possible exception of the Gulf coast region from eastern Wakulla County in the panhandle south to Hernando County in the central peninsula. There is one record from the Florida Keys.
County data coming soon.
If you have a new or interesting observation for this species, please email the herpetology staff at the Florida Museum.
Ernst, C.H. and E.M. Ernst. 2003. Snakes of the United States and Canada. Smithsonian Institution Press, Washington, DC. 668 pp.
Krysko, K.L., K.M. Enge, and P.E. Moler. Amphibians and Reptiles of Florida. 2019. University of Florida Press, Gainesville, Florida. 706 pp.
Powell, R., R. Conant, and J.T. Collins. 2016. Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America. Fourth edition. Houghton Mifflin Harcourt Publishing Company, Boston and New York. xiv + 494 pp.
Rossman, D.A., N.B. Ford, and R.A. Seigel. 1996. The Garter Snakes: Evolution and Ecology. First edition. University of Oklahoma Press, 336 pp.
Share your observations
You can help scientists better understand the biology and distribution of this species by sharing your observations. Send photos or videos of interesting observations, along with associated information, by emailing the herpetology staff at the Florida Museum for documentation in the Museum’s Herpetology Master Database. You can also post your observations on iNaturalist.
Additional helpful information
Do you have snakes around your house? Learn how to safely co-exist with snakes.
Still have questions about snakes or identifications? Feel free to email the herpetology staff at the Florida Museum with your questions or feedback on this profile.
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