Plain-bellied Watersnake
Nerodia erythrogaster • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia erythrogaster
Found throughout the southeastern and south-central United States, extending north into the Midwest and parts of the Great Plains, primarily from Texas east to Georgia and north to Illinois and Indiana.
Look up Plain-bellied Watersnake in the Snake Encyclopedia →Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia erythrogaster
Conservation
IUCN Red List status is Least Concern. Populations are generally stable, though locally threatened by wetland drainage, habitat fragmentation, and direct persecution by humans.
Physical Description
The specimen exhibits a dark brown to nearly black dorsal coloration, with subtle darker patterning or banding visible under light, and a robust body typical of aquatic watersnakes. The head is somewhat distinct from the neck, and scales are heavily keeled, providing a matte texture suited for an aquatic lifestyle.
Size & Dimensions
Estimated specimen length is approximately 30 to 40 inches. Typical adults range from 30 to 48 inches (76 to 122 cm), with maximum records approaching 62 inches (157 cm).
Habitat
Inhabits permanent and temporary bodies of freshwater, including swamps, marshes, sloughs, oxbow lakes, slow-moving rivers, ponds, and drainage ditches. Often found basking on logs, rocks, or shoreline vegetation near water.
Diet & Feeding
Preys primarily on amphibians, fish, and occasionally crayfish. Uses an active foraging strategy along aquatic margins, catching prey directly in the water or shallows and subduing it through constriction or direct swallowing.
Reproduction
Ovoviviparous (gives birth to live young). Mating occurs in the spring, and females typically give birth to litters ranging from 10 to 30+ young in late summer or early autumn.
Look-alikes
Frequently confused with other watersnakes (Nerodia species) such as the Northern Watersnake (Nerodia sipedon) and Cottonmouths (Agkistrodon piscivorus). Distinguished from cottonmouths by round pupils, lack of facial pits, and slenderer head profile.
Conservation Status
IUCN Red List status is Least Concern. Populations are generally stable, though locally threatened by wetland drainage, habitat fragmentation, and direct persecution by humans.
Cultural Significance
Plays an important ecological role in controlling amphibian and fish populations in wetland ecosystems. Often misunderstood and mistakenly killed due to superficial resemblance to pit vipers.
Notable Features
Demonstrates strong semi-aquatic adaptations, including dorsal nostrils positioned high on the snout for breathing while mostly submerged, and heavily keeled scales that reduce glare and improve traction in wet environments.