Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Commonly found throughout North America, specifically Central and Eastern United States and parts of Southeast Canada, ranging from Southern Ontario to North Carolina and west to Colorado.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous; aglyphous (lacks specialized fangs).
Danger Level
Low Risk; while non-venomous, they are famously defensive and will bite repeatedly if handled, leading to painful but medically insignificant lacerations. Saliva may contain mild anticoagulants.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
Least Concern (IUCN); widespread and abundant, though often killed by humans who mistake them for venomous Cottonmouths.
Physical Description
Strongly keeled scales with a heavy, keeled appearance. Coloration varies from brown to tan with dark crossbands or blotches that often fade with age. Labial scales have dark vertical sutures. Round pupils and a head that is slightly wider than the neck.
Size & Dimensions
The specimen appears to be an adult. Typical adult length ranges from 60 to 110 cm (2 to 3.5 feet), with a maximum recorded length of about 150 cm.
Habitat
Primarily semi-aquatic habitats including lakes, ponds, marshes, rivers, and streams; often found basking on rocks, logs, or hanging from branches over water.
Behavior & Temperament
Diurnal and crepuscular; highly defensive when cornered or handled. Will flatten its head and body to appear larger, emit musk from cloacal glands, and bite vigorously. Often seen 'periscoping' (as pictured) to scan surroundings.
Diet & Feeding
Active foragers that primarily consume fish and amphibians (frogs, toads, salamanders). They use their sense of smell and vibration to locate prey and swallow it alive.
Reproduction
Viviparous (gives birth to live young); breeding occurs in spring with 15–30 young typically born in late summer or autumn.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Commonly confused with the Northern Cottonmouth (Agkistrodon piscivorus). Distinguishable by round pupils (Cottonmouths have vertical slits), absence of facial pits, and labial sutures (Cottonmouths have a dark stripe through the eye).
Conservation Status
Least Concern (IUCN); widespread and abundant, though often killed by humans who mistake them for venomous Cottonmouths.
Cultural Significance
Ecologically vital for controlling fish and amphibian populations; frequently serves as an educational ambassador for dispelling myths about water snakes in North America.
Notable Features
Often periscopes its head above the water's surface to breathe and observe. It possesses an anticoagulant in its saliva that causes bites to bleed more than expected.