Common Rainbow Snake, Eel Moccasin, Southern Florida Rainbow Snake
Basic description
Most adult Rainbow Snakes are about 27–48 inches (70–122 cm) in total length. Adults are large, thick bodied, and quite beautiful. These snakes are mostly glossy black (iridescent blue in the sunlight) with three thin red stripes running down the back and sides. The lower sides of the body are yellow or pink, and the chin and throat are yellow. The tail tip ends in a pointed, horny scale. Juveniles are similar in appearance to adults.
Rainbow Snake. Photo courtesy of Ryan Means.
Rainbow Snake swimming in the Wakulla River. Photo courtesy of Ryan Means.
Range in Florida
Rainbow Snakes are found throughout the Panhandle and in parts of the northern peninsula along the St. Marys, St. Johns, and Suwannee river drainages. A separate and potentially extinct population is known only from Fisheating Creek in Glades County.
Assessment of risk to people and pets
Non-venomous.Rainbow snakes are not dangerous to people or pets.
Comparison with other species
Red-bellied Mudsnake (Farancia abacura)Non-venomous Red-bellied Mudsnakes are glossy black with around 50 red to pink bars that cross the belly and extend up onto the sides of the body.
Adult Mudsnake, ventral (belly) coloration. Photo courtesy of Todd Pierson. Rainbow Snake. Photo courtesy of Ryan Means.
Black Swampsnake (Liodytes pygaea)Non-venomous Black Swampsnakes lack the reddish-pink triangular pattern on the sides and the alternating black and reddish-pink bars on the belly typically found on Rainbow Snakes.
Black Swampsnake with belly color showing. Photo courtesy of Luke Smith. Rainbow Snake. Photo courtesy of Ryan Means.
Most adult Rainbow Snakes are about 27–48 inches (70–122 cm) in total length, with a record length recorded of 68.3 inches (173.3 cm). Adults are large, thick bodied, and quite beautiful. These snakes are mostly glossy black (iridescent blue in the sunlight) with three thin red stripes running down the body, one down the middle of the back and one on each side. The lower sides of the body are yellow or pink fading into the red belly. Black spots on each belly scale form three lines of dots down the belly. The chin and throat are yellow. The tail tip ends in a pointed, horny scale. The scales are mostly smooth and arranged in 19 scale rows at midbody. The pupil is round. Juveniles are similar in appearance to adults.
Rainbow Snakes are primarily aquatic and mainly inhabit clear waters of springs and rivers. They are also sometimes observed in creeks, lakes, cypress swamps, marshes, and tidal mudflats. Rainbow Snakes have been found under floating vegetation, within banks at water’s edge, and under shoreline debris such as Spanish moss and logs. They have also been plowed up in fields several hundred yards from the nearest water. They are occasionally observed crossing roads at night, especially during or after heavy rains.
These docile snakes do not bite in defense. If approached or cornered, Rainbow Snakes will often remain perfectly still or crawl away very slowly. If captured, they may press the pointed but harmless tail tip against the attacker, and they may release foul-smelling musk from two glands in the base of the tail.
Rainbow Snakes are nocturnal (active at night) and feed primarily on freshwater American eels, earning them the nickname “Eel Moccasin.” Juveniles are known to eat tadpoles and earthworms. Prey are swallowed alive without constriction.
In Florida, females can lay 10–52 eggs. Females construct a nesting cavity in loose soil, sand, or debris and may stay with the eggs until they hatch. The eggs typically hatch between September and October.
Common Rainbow Snake (Farancia erytrogramma erytrogramma) Common Rainbow Snakes are found throughout the Panhandle and in parts of the northern peninsula along the St. Marys, St. Johns, and Suwannee River drainages.
Southern Florida Rainbow Snake (Farancia erytrogramma seminola) Southern Florida Rainbow Snakes are known only from a single population in Fisheating Creek, Glades County, which flows into the western side of Lake Okeechobee in the southern peninsula. This population is possibly extinct.
Rainbow Snakes are secretive, highly aquatic, and rarely seen. Occasionally they can be found crossing roads between bodies of water, usually on rainy nights. Swimmers and divers occasionally report seeing them slowly crawling along the bottom of clear, spring-fed rivers.
Some people believe that this snake has a stinger on the tip of the tail. However, this is not the case. The pointy scale on the tip of the tail is completely harmless.
The Southern Florida Rainbow Snake is one of the rarest snakes in the United States. Only three specimens have ever been found, all between 1949 and 1952. The only known available specimen is secured in the Florida Museum of Natural History at the University of Florida. At the time when this subspecies was formally described, two other snakes were also collected from the same area, but these specimens were unfortunately never deposited in a recognized museum’s collection and have been lost. Several searches have been made for Southern Florida Rainbow Snakes since the 1950s, but all have been unsuccessful.
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. 2019. Amphibians and Reptiles of Florida. 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.
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.
Banner photo courtesy of Ryan Means. Please credit any photographers on the page and see our copyright policy.
