Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Venomous Status
Non-venomous - aglyphous (lacks specialized fangs)
Danger Level
Harmless/Low Risk. While non-venomous, they are famously defensive and will bite readily if handled. Bites may bleed profusely due to anticoagulant properties in their saliva but are not life-threatening.
Geographic Range
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 and Oklahoma.
Conservation Status
Least Concern (IUCN). Generally abundant, though locally threatened by wetland destruction and persecution by humans who mistake them for venomous species.
Physical Description
Variable coloration from brownish to grey or reddish with dark crossbands or blotches that are wider than the light spaces between them. Bands often break into alternating blotches toward the tail. Heavily keeled scales and a stout body. Pupils are round.
Size & Dimensions
Specimen in image appears to be an adult around 60-90 cm. The species typically ranges from 60 to 105 cm (24-42 inches), with a record maximum of roughly 150 cm (59 inches).
Habitat
Primarily semi-aquatic, found in lakes, ponds, rivers, streams, and marshes. Often seen basking on rocks, logs, or hanging from branches over water. Preference for slow-moving or standing water.
Behavior & Temperament
Diurnal and crepuscular; highly active swimmers. When threatened, they often flatten their bodies and heads to appear larger and emit a foul-smelling musk. They are quick to strike in self-defense.
Diet & Feeding
Carnivorous; feeds primarily on fish and amphibians (frogs, toads, salamanders). An active forager that swallows prey alive, often using the shoreline to help pin struggling animals.
Reproduction
Viviparous (gives birth to live young) rather than laying eggs. Litter sizes are large, ranging from 15 to 30 young on average, typically born in late summer (August to October).
Venom Profile
Venom Type
Non-venomous - no medically significant venom.
AI-generated — see a qualified source if acting on this. For any snakebite, call emergency services immediately.
Look-alikes
Frequently confused with the Northern Cottonmouth (Agkistrodon piscivorus). Distinguishable by round pupils (vs. vertical slits), lack of heat-pits, and the row of dark vertical lines on the labial scales (lip).
Conservation Status
Least Concern (IUCN). Generally abundant, though locally threatened by wetland destruction and persecution by humans who mistake them for venomous species.
Cultural Significance
Often unfairly maligned due to its aggressive defensive display and resemblance to cottonmouths. Ecologically vital for controlling fish and amphibian populations in North American wetlands.
Notable Features
Excellent swimmers capable of diving and remaining submerged for several minutes. Their saliva contains an anticoagulant which causes bite wounds to bleed more than typical small scratches.