Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Eastern and Central North America, spanning from southern Canada to North Carolina and west to Colorado and Oklahoma.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous (Aglyphous)
Danger Level
Harmless. While they are non-venomous, they are highly defensive and will bite readily if handled, leading to superficial scratches and bleeding due to anticoagulants.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
Least Concern (IUCN). Generally abundant, though often persecuted due to confusion with venomous species.
Physical Description
Thick-bodied snake with dark crossbands near the head that break into alternating dorsal and lateral blotches further down the body. Scales are heavily keeled (rough). Ground color varies from gray to brownish-tan. Head is relatively flat and wide; eyes have round pupils.
Size & Dimensions
The specimen in the image appears to be a juvenile or sub-adult, approximately 18-24 inches (45-60 cm) long. Adults typically range from 24 to 42 inches (60-107 cm).
Habitat
Found near freshwater sources including lakes, ponds, rivers, marshes, and canals. They are semi-aquatic, often seen basking on rocks or logs near the water's surface.
Behavior & Temperament
Diurnal but can be active at night during warm spells. They are very wary and typically dive into water when approached. If cornered, they flatten their bodies, hiss, and strike repeatedly. They may also release a foul-smelling musk.
Diet & Feeding
Primarily piscivorous and insectivorous when young; adults eat fish, frogs, toads, and salamanders. They are active foragers that hunt along the shoreline or underwater.
Reproduction
Viviparous (gives birth to live young). Mating occurs in spring, and females give birth to 15-30 young in late summer or early autumn.
Venom Profile
Non-venomous - no medically significant venom. Saliva may contain mild anticoagulants to aid in swallowing slippery fish.
Look-alikes
Commonly confused with the Northern Cottonmouth (Agkistrodon piscivorus). Distinct from Cottonmouths by their round pupils (vs. vertical slits), absence of heat-sensing pits, and labial scales that have dark vertical lines.
Conservation Status
Least Concern (IUCN). Generally abundant, though often persecuted due to confusion with venomous species.
Cultural Significance
Often misunderstood and killed by humans who mistake them for venomous snakes. They play a vital ecological role in controlling fish and amphibian populations and serve as prey for larger birds and mammals.
Notable Features
Excellent swimmers that can remain submerged for extended periods. Their 'keeled' scales give them a very rough texture compared to many other common North American colubrids.