Plain-bellied Watersnake Nerodia erythrogaster - Endangered

Adult from Jackson County
Juvenile from Jackson County

Identification: This distinctive watersnake is unique for its jet black dorsal color and bright, red-orange "copper" belly. Though other heavy-bodied snakes may appear dark or black from above, no other large Indiana snake has such a colorful underbelly. Juveniles are markedly less distinctive and are light gray-brown with darker bands. Though neonates have a tinge of orange-brown coloration between their bands and on their underside, the brilliant orange belly does not develop until later in life. This is a large, heavy-bodied snake with adult females routinely exceeding four feet (1.2 m) in length and some individuals over five feet (1.5 m) long.

Similar Species: Though juvenile plain-bellied watersnakes could be mistaken for northern watersnakes, this species lacks any substantial patterning on its underbelly and has coppery-red coloration infused between the dorsal bands. Adult plain-bellied watersnakes are very distinctive among Indiana snakes, as mentioned above.

Distribution: The variant (subspecies) of plain-bellied watersnake found in Indiana is known as the "copper-bellied watersnake" and is peculiar in that a sub-population within this subspecies is federally threatened. Copper-bellied watersnakes in northeastern Indiana, and adjacent Michigan and Ohio, are rare following dramatic declines during the latter half of the twentieth century and, as a result, are protected. The next nearest population is found in the swampy bottomlands of the Muscatatuck lowlands in southeastern Indiana, where the snakes are abundant and have no federal protection. These snakes are also common along the lower Wabash and Ohio Rivers in the swamplands of southwestern Indiana. Here, some individuals have much paler bellies and are more similar to the yellow-bellied variant to the south. Across all three areas where these snakes occur in Indiana, they share the commonality of being strictly wetland-associated snakes that feed almost entirely on amphibians. As a result, they make frequent long-distance movements overland between isolated, often ephemeral wetlands.

Marshland in Jackson County
Lowland Stream in Dubois County

Distribution Map
Distribution map of Plain-bellied Watersnake (Nerodia erythrogaster)
Photographs