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| Gulf Salt Marsh Snake, Nerodia clarkii clarkii (Baird and Girard, 1853). Photograph of captive snake. Adults reach 914 mm in total length. Litter size ranges from 3-19. This is the only endemic water snake know to use brackish water. It is known to use its tongue to lure fish. N. clarkii ranges from the Atlantic Coast of Florida, around peninsular Florida to coastal Texas. It appears to be most closely related to Nerodia sipedon. |
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| The Plain Belly Water Snake, Nerodia erythrogaster (Forester, 1771). A Blotched Water Snake, N. e. transversa, from eastern Kansas. Adult size is about 1.49 m. It has a distribution ranging from Michigan to the east coast and west to Texas and south into Mexico. The distribution is often discontinuous. |
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| Banded Water Snake, Nerodia fasciata (Linnaeus, 1766). Adults reach about 1.5 m. It uses a variety of freshwater habitats from North Carolina to Texas. Banded Water Snakes eat a long list of fish and amphibian species. Litter sizes as large as 57 young have been reported, but the mean is about 20. The upper photo is an individual from Onslow County, North Carolina. |
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| The Diamondback Water Snake, Nerodia rhombifera (Hallowell, 1852). Photographed in southern Mississippi (top) and in Alexander County, Illinois (bottom). This is a species of the south central USA, which extends into Mexico to Veracruz. It rarely wanders far from water and feeds on fish, with some populations specializing in feeding on frogs. Adults reach 1.6 m in total length. Litter sizes range from 11 to 62. |
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| The Northern Water Snake, Nerodia sipedon (Linnaeus, 1758). The Northern Water Snake is ubiquitous over much of eastern North America and their are few bodies of permanent water where they cannot be found. Food includes mostly fish, but they will eat almost any vertebrate they can swallow and many invertebrates. Adult size is about 1.5 m. Females may require two years to mature in the northern portions of the range, and they have been reported to give birth to litters of up to 99 young. However, the mean litter size is about 20 young. |
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| The Brown Water, Nerodia taxispilota (Holbrook, 1842). Adults reach 1.7 m. It ranges from southeast Virginia southward to southern Florida and westward to Alabama. Coastal populations will apparently enter brackish water, but for the most part this species uses still freshwaters of swamps and lakes and slow moving rivers. They feed mostly on fish, and show a preference for ictalurid catfish. Litter size ranges from 4-61, with the mean probably about 18 young. |
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| Nerodia contains 9 species distributed in North and Central America. Collectively they are referred to as Water Snakes. They area all associated with freshwater environments with the exception of Nerodia clarkii which uses the brackish waters of coastal environments. The Brown Water Snake, N. taxispilota, uses large streams, rivers and reservoirs. The Florida Green Water Snake uses open canopy habitats, and Harter's Water Snake, N. harteri, uses rocky riffles in streams. All of the other species tend to use a variety of aquatic habitats. The Brown Water Snake tends to specialize in eating catfish, but diet information for the other species suggest they feed primarily on fish and frogs and have not specialized their diet. Females tend to be larger than males, males tend to mature in 2-3 years, while females mature in 3-4 years. All species are viviparous with females giving birth in the summer. These snakes also are often visible when they bask in bushes, or on rocks along streams. Alfaro and Arnold (2001 Molecular Phylogenetics and Evolution 21:408-423) present evidence that Nerodia is a monophyletic clade if Regina septemvittata, Regina grahamii, and Tropidoclonion are included. Not surprisingly, they found the sister to Nerodia are the Garter Snakes of the genus Thamnophis. For details on these snakes see Gibbons and Dorcas (2004, North American Water Snakes, A Natural History; University of Oklahoma Press). |
