Plain-bellied Watersnake
Nerodia erythrogaster • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia erythrogaster
Found primarily in the southeastern and south-central United States, extending from Texas and Louisiana north into Kansas and Illinois, and east to Georgia and the Carolinas.
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 local threats include habitat loss from wetland drainage and road mortality.
Physical Description
Displays a stout, heavy-bodied form with dark brown to blackish dorsal coloration, sometimes showing faint reddish or patterned undertones on the lower flanks. The head is distinct from the neck with rounded snout proportions, and the scales are heavily keeled, contributing to a matte appearance. The underside is typically plain yellow, orange, or red without extensive patterning.
Size & Dimensions
The pictured specimen appears to be an adult around 30 to 40 inches in length. Typical adults range from 30 to 48 inches (76 to 122 cm), with maximum recorded lengths approaching 62 inches (157 cm).
Habitat
Inhabits aquatic environments including swamps, marshes, rivers, ponds, and slow-moving streams. Prefers areas with dense marginal vegetation, muddy substrates, and plenty of basking sites such as logs or shoreline rocks.
Diet & Feeding
Primarily feeds on aquatic prey including fish, frogs, tadpoles, and salamanders. Utilizes an active foraging strategy along shorelines and in shallow water, capturing prey directly by mouth.
Reproduction
Viviparous (gives live birth). Mating typically occurs in the spring, and females give birth to litters averaging 10 to 20 young in late summer or early autumn.
Look-alikes
Frequently confused with cottonmouths (Agkistrodon piscivorus) due to dark coloration, stocky build, and aquatic habits. Can be distinguished by round pupils, lack of facial pit, differently shaped head, and a tendency to flee rather than display defensive postures.
Conservation Status
IUCN Red List status is Least Concern. Populations are generally stable, though local threats include habitat loss from wetland drainage and road mortality.
Cultural Significance
Plays an important ecological role as both predator and prey within wetland ecosystems, helping to regulate amphibian and small fish populations.
Notable Features
Known for being able to travel relatively far overland away from water sources compared to other watersnake species, and often displays a feisty disposition when cornered, flattening its body and striking repeatedly.