Northern Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Found throughout the eastern and central regions of North America, ranging from southern Canada down through the United States to the Gulf Coast, and westward to parts of Colorado and Kansas.
Look up Northern Watersnake in the Snake Encyclopedia →Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
IUCN Red List status is Least Concern. The species is widespread and abundant throughout its natural range, though local populations can face threats from habitat degradation, road mortality, and intentional killing due to misidentification.
Physical Description
Displays a stout body with heavily keeled scales. Coloration typically consists of brownish, reddish, or greyish background with dark crossbands on the neck and alternating blotches along the back and sides. The belly is often marked with yellowish, whitish, or reddish patterns with dark crescents or spots. The head is relatively distinct from the neck, and eyes feature round pupils.
Size & Dimensions
The specimen pictured appears to be a medium-sized adult. Typical total length for the species ranges from 61 to 106 cm (24 to 42 inches), with occasional larger individuals reaching up to 135 cm (53 inches).
Habitat
Inhabits permanent and temporary bodies of fresh water such as rivers, streams, lakes, ponds, marshes, swamps, and artificial impoundments. Usually found near the water's edge, basking on rocks, logs, or low hanging branches.
Diet & Feeding
Predominantly feeds on aquatic prey including fish, amphibians (frogs, toads, salamanders), crayfish, and occasionally small mammals or birds. Hunts primarily as an active forager and ambush predator near and within water.
Reproduction
Viviparous (gives live birth). Mating typically occurs in the spring (April to June), and females give birth to litters averaging 20 to 30 young in late summer or early autumn.
Look-alikes
Frequently confused with venomous species such as cottonmouths (Agkistrodon piscivorus) or copperheads (Agkistrodon contortrix) due to pattern overlap and defensive posturing. Can also be confused with other watersnake species within the genus Nerodia.
Conservation Status
IUCN Red List status is Least Concern. The species is widespread and abundant throughout its natural range, though local populations can face threats from habitat degradation, road mortality, and intentional killing due to misidentification.
Cultural Significance
Plays a vital role in aquatic and riparian ecosystems as both a predator of fish and amphibians and as prey for larger birds, mammals, and other reptiles. Often misunderstood and persecuted by humans fearing dangerous look-alikes.
Notable Features
Exhibits strong aquatic adaptations including the ability to remain submerged for extended periods, highly keeled dorsal scales, and nostrils positioned slightly higher on the snout to facilitate breathing at the water surface.