Northern Watersnake
Nerodia sipedon • Colubridae (Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon)
Widespread across eastern and central North America, ranging from southern Canada south to the Carolinas and west to Colorado and Oklahoma.
Look up Northern Watersnake in the Snake Encyclopedia →Family
Colubridae (Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon)
Conservation
Least Concern (IUCN Red List). Abundant across its range, though occasionally persecuted due to misidentification with venomous snakes.
Physical Description
Dark brown to greyish-black body with dark crossbands near the head that transition into alternating dorsal and lateral blotches further down the body. Scales are strongly keeled, giving a rough texture. Head is distinct from the neck with dark vertical labial bars visible along the lip margins.
Size & Dimensions
Specimen shown is likely an adult around 60-90 cm (2-3 feet) in length. Adults typically range from 60 to 110 cm (24 to 42 inches), with record lengths reaching around 140 cm (55 inches).
Habitat
Aquatic and semi-aquatic habitats including rivers, streams, lakes, ponds, marshes, and swamps. Frequently found resting on rocks, logs, or vegetation near water edges.
Diet & Feeding
Carnivorous active hunter feeding predominantly on fish, frogs, toads, tadpoles, salamanders, and occasionally small mammals or birds.
Reproduction
Viviparous (gives birth to live young). Female gives birth to a litter of 15-30 (sometimes up to 90) live young in late summer to early autumn.
Look-alikes
Frequently confused with the venomous Cottonmouth / Water Moccasin (Agkistrodon piscivorus) and Copperhead (Agkistrodon contortrix). Watersnakes are distinguished by round pupils, absence of facial heat-sensing pits, labial bars along the lip scales, and narrower heads when relaxed.
Conservation Status
Least Concern (IUCN Red List). Abundant across its range, though occasionally persecuted due to misidentification with venomous snakes.
Cultural Significance
Plays a critical ecological role in controlling fish and amphibian populations in aquatic ecosystems. Often misunderstood and needlessly killed due to resemblance to venomous pit vipers.
Notable Features
Keeled scales give a dull, rough appearance when dry. Capable of swimming efficiently and diving underwater for extended periods to forage or escape predators.