Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Found throughout Central and Eastern North America, ranging from Southern Ontario and Quebec in Canada, south to Louisiana and Florida, and as far west as Colorado.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous; lacks fangs and venom glands (Aglyphous).
Danger Level
Low Risk; while non-venomous, they are famously feisty and will bite repeatedly if handled, often releasing a foul-smelling musk. Bites can cause minor localized bleeding due to anticoagulant properties in their saliva.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
Least Concern (IUCN); very common throughout its range, though often killed by humans who mistake it for a Cottonmouth.
Physical Description
Heavy-bodied snake with keeled scales. Coloration ranges from brownish to grey with dark crossbands near the head that break into alternating dorsal and lateral blotches further down the body. Round pupils and labial scales with dark vertical stitching.
Size & Dimensions
Specimen appears to be an adult of approximately 2-3 feet. Species typically ranges from 24 to 42 inches (61–107 cm); females are significantly larger than males.
Habitat
Primarily aquatic; found in ponds, lakes, rivers, canals, and marshes. Often seen basking on rocks, logs, or as seen here, on aquatic vegetation like lily pads.
Behavior & Temperament
Highly active during the day (diurnal) and night (nocturnal) in warm weather. Extremely defensive when cornered; they will flatten their heads to appear larger, hiss, and bite aggressively if they cannot flee into the water.
Diet & Feeding
Generalist carnivore focusing on fish and amphibians. They use an active foraging strategy, often 'fishing' with an open mouth through vegetation or cornering prey against the shoreline.
Reproduction
Viviparous (gives birth to live young); breeding occurs in spring with 15 to 30 young typically born in late summer or early autumn.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Frequently confused with the venomous Cottonmouth (Agkistrodon piscivorus). Distinct from Cottonmouths by their round pupils (vs. vertical), lack of heat-sensing pits, and dorsal patterns that usually consist of complete bands near the neck.
Conservation Status
Least Concern (IUCN); very common throughout its range, though often killed by humans who mistake it for a Cottonmouth.
Cultural Significance
Often misunderstood and maligned due to its aggressive defensive nature. Ecologically vital as a mid-level predator that controls populations of fish and amphibians.
Notable Features
Excellent swimmers that can remain submerged for extended periods. Their saliva contains an anticoagulant that causes bites to bleed more profusely than expected for a small wound.