Description: The mud snake is a large (up to 81 in – 207 cm), non-venomous, highly-aquatic snake that is seldom seen because of its secretive habits. Adults are fairly heavy-bodied and are glossy black on the back. The belly has a red (or pink)-and-black checkerboard pattern and the red often extends up the sides of the body. They have small, dark eyes and often have some yellow coloration on the head. The scales are smooth and shiny and the anal plate is divided. Many mud snakes from the Savannah River Site have double anal plates. Mud snakes have a spine-like scale at the tip of their tail, and thus are sometimes known as “horn snakes.” Male mud snakes are smaller than females but have relatively longer and thicker tails. Young mud snakes resemble adults but their red coloration extends farther up the sides, at times giving them a banded appearance. Mud snakes completely lacking red pigment (anerythristic) are encountered fairly frequently in the Southeast.
Distribution and Habitat: Mud snakes are found in the Coastal Plain of the southern United States from southern Virginia south throughout Florida. They also range up the Mississippi drainage as far north as Southern Illinois and west to eastern Texas. In our region, mud snakes are generally restricted to the Coastal Plain but extend somewhat into the Piedmont in western Georgia.
Mud snakes are found in a variety of aquatic habitats including seasonal wetlands, ditches, Carolina bays, cypress swamps, marshes, slow-moving streams, and the heavily-vegetated margins of lakes and ponds. In South Carolina young mud snakes often inhabit seasonal wetlands and move to more permanent water bodies as adults. Although highly aquatic, mud snakes will move considerable distances overland between water bodies and are sometimes found far from water.
Habits: Mud snakes are highly aquatic and spend most of their lives hidden amongst aquatic vegetation and debris. Unlike many of the watersnakes on our region, mud snakes seldom bask out of the water and thus are seldom seen, even by dedicated naturalists and herpetologists. Mud snakes are perhaps most frequently encountered crossing roads adjacent to aquatic habitats, particularly on rainy summer nights. When captured, mud snakes do not bite but may press their pointed tail tip harmlessly into their captor.
As adults, mud snakes feed primarily on giant aquatic salamanders (Amphiuma and Siren) but young snakes may also consume other amphibians including salamander larvae and tadpoles. F emales lay eggs in early summer in sandy upland habitats near water and sometimes attend the eggs until they hatch. Although large females may lay over 100 eggs, average clutch size is probably closer to 20-30 eggs. Young hatch in late summer but may overwinter in the nest before emerging. Due to their secretive habits, relatively little is known about the ecology of mud snakes. Much of what we do know is from research conducted at the Savannah River Ecology Lab.
Interesting facts: Mud snakes are sometimes known as “hoop snakes” because of the myth that they will bite their own tail and roll after people.
Conservation Status: Although seldom seen, mud snakes are fairly common and are not protected in our region. However, this species relies on aquatic habitats and amphibian prey may put them at risk as wetlands are destroyed or degraded.
Willson, J. D., C. T. Winne, M. E. Dorcas, and J. W. Gibbons. 2006. Post-drought responses of semi-aquatic snakes inhabiting an isolated wetland: Insights on different strategies for persistence in a dynamic habitat. Wetlands 26:1071-1078.
Seigel, R. A., J. W. Gibbons, and T. K. Lynch. 1995. Temporal changes in reptile populations: Effects of a severe drought on aquatic snakes. Herpetologica, 51:424-434.
Semlitsch, R. D., J. H. K. Pechmann, and J. W. Gibbons. 1988. Annual emergence of juvenile mud snakes (Farancia abacura) at aquatic habitats. Copeia 243-245.
Account author: J.D. Willson
Juvenile mud snake
Defensive tail curling
Mud snake eating an amphiuma
Anerythristic mud snake from South Carolina