Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Common throughout eastern and central North America, ranging from southern Ontario and Quebec in Canada, south to Louisiana and Florida, and west to Colorado and Nebraska.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous (Aglyphous - lacks specialized fangs)
Danger Level
Low Risk (Harmless). Though non-venomous, they are highly defensive and will bite repeatedly if handled, often Musk and defecate as a deterrent. Bites may bleed profusely 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). Generally common throughout their range, though they face threats from habitat destruction, water pollution, and being frequently killed by humans who mistake them for venomous Cottonmouths.
Physical Description
Heavy-bodied snake with keeled scales. Coloration ranges from grayish-brown to reddish with dark crossbands near the head that break into alternating dorsal and lateral blotches further down the body. The head is relatively flat and slightly wider than the neck, and pupils are round.
Size & Dimensions
The specimen in the image appears to be an adult, approximately 2 to 3 feet in length. Typical adult size for the species is 24 to 42 inches (61 to 107 cm), with a maximum record of about 59 inches.
Habitat
Found near freshwater sources such as lakes, rivers, ponds, marshes, and canals. Often seen basking on rocks (as in the image), logs, or overhanging branches. They occupy a wide range of elevations from sea level to mountainous areas.
Behavior & Temperament
Diurnal and crepuscular, often seen basking in sunlight. Known for a very defensive temperament; when threatened, they flatten their bodies to appear larger and will strike readily. They are excellent swimmers and often dive to escape predators.
Diet & Feeding
Active foragers that primarily eat fish and amphibians (frogs, toads, salamanders). They use a strategy of grabbing prey and swallowing it alive, sometimes dragging larger prey to the shore.
Reproduction
Viviparous (gives birth to live young). Mating occurs in spring, and females give birth to 15-30 young between August and October. Large females may have larger litters.
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), lack of heat-sensing pits, and labial bars (vertical lines on the scales bordering the mouth). Also confused with Copperheads due to the banding.
Conservation Status
Least Concern (IUCN). Generally common throughout their range, though they face threats from habitat destruction, water pollution, and being frequently killed by humans who mistake them for venomous Cottonmouths.
Cultural Significance
Ecologically significant as a mid-level predator that controls fish and amphibian populations. They serve as a vital food source for larger predators like herons and raccoons. Frequently misunderstood and persecuted due to their resemblance to venomous species.
Notable Features
Possess keeled scales that give the snake a rough texture. Their saliva contains a mild anticoagulant that prevents prey's blood from clotting, which can cause human bite wounds to bleed significantly despite the lack of venom.