Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Found throughout eastern and central North America, from southern Ontario and Quebec in Canada, south to Louisiana and Florida in the United States, and as far west as Colorado and Oklahoma.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous (Aglyphous)
Danger Level
Low Risk; Harmless to humans but known to be extremely defensive. They may bite repeatedly and secrete a foul-smelling musk if handled, but they possess no venom.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
IUCN Red List: Least Concern. They are common and adaptable, though often persecuted due to confusion with venomous species.
Physical Description
Heavy-bodied snake with keeled scales. Coloration is typically brown to grayish with dark crossbands near the head that break into alternating dorsal and lateral blotches further down the body. The specimen pictured appears dark and muddy, which often obscures the pattern in adults. Eyes have round pupils.
Size & Dimensions
The specimen in the image appears to be an adult, approximately 24 to 36 inches long. Typical size range for the species is 24 to 42 inches (61–107 cm), with a record length of about 55 inches.
Habitat
Highly aquatic; commonly found in lakes, ponds, marshes, rivers, and streams. Prefers areas with ample basking spots like logs or rocks and shoreline vegetation for cover.
Behavior & Temperament
Diurnal and crepuscular; active during the day basking or hunting. They are notorious for a feisty temperament; when cornered, they flatten their bodies to look larger and will strike and bite readily. Highly skilled swimmers.
Diet & Feeding
Primarily piscivorous (fish) and carnivorous. They feed on various fish species, frogs, toads, salamanders, and occasionally large invertebrates. They use a 'search and grab' strategy rather than constriction.
Reproduction
Viviparous (gives birth to live young); breeding usually occurs in spring, and females give birth to 15 to 30 young in late summer or early autumn.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Frequently confused with the venomous Northern Cottonmouth (Agkistrodon piscivorus). Distinct from Cottonmouths by their round pupils (vs. vertical), lack of heat-sensing pits, and labial bars (vertical dark lines on the lip scales).
Conservation Status
IUCN Red List: Least Concern. They are common and adaptable, though often persecuted due to confusion with venomous species.
Cultural Significance
Often misunderstood and killed due to its resemblance to the Cottonmouth. Ecologically significant as a mid-level predator that maintains fish and amphibian population health.
Notable Features
Their saliva contains a mild anticoagulant that can cause a bite wound to bleed more than expected, which contributes to the myths regarding their 'venomous' nature.