Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: sipedon
Commonly found throughout North America, specifically Central and Eastern United States and Southeastern Canada. It spans from the Atlantic coast to the Mississippi River and as far south as North Carolina.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous
Danger Level
Harmless / Low Risk. While non-venomous, they are famously defensive and will bite repeatedly if handled, often secreting a foul-smelling musk. Their saliva contains anticoagulants that can cause minor localized bleeding.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: sipedon
Conservation
IUCN Red List: Least Concern. The species is widespread and adaptable, though localized populations face threats from water pollution and habitat destruction.
Physical Description
A heavy-bodied snake with strongly keeled scales. Coloration is typically brownish, grayish, or tan with dark crossbands near the head that break into alternating dorsal and lateral blotches further down the body. The head is relatively flat and distinct from the neck; eyes have round pupils.
Size & Dimensions
The specimen in the image appears to be a sub-adult or adult, approximately 60-90 cm. Typical adult size range is 61-107 cm, with a maximum recorded length of approx. 135 cm.
Habitat
Semi-aquatic species found near freshwater sources including lakes, ponds, rivers, marshes, and canals. They are often found basking on rocks, logs, or overhanging branches and hide under debris near shorelines.
Behavior & Temperament
Highly defensive temperament when cornered or handled. They are active both during the day and night (diurnal and nocturnal), often seen basking during the day and foraging at night. They will flatten their heads and bodies to appear larger when threatened.
Diet & Feeding
Primarily piscivorous and carnivorous, feeding on various fish, frogs, toads, salamanders, and occasionally small mammals or birds. They use an active foraging strategy and swallow prey alive or pin it against underwater structures.
Reproduction
Viviparous (gives birth to live young). Breeding occurs in the spring, and females typically give birth to 15-30 young (can be up to 100) between August and October.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Commonly confused with the venomous Cottonmouth (Agkistrodon piscivorus). Distinguishable by the round pupils (vs vertical), lack of heat-sensing pits, and the presence of labial bars (vertical dark lines on the scales bordering the mouth).
Conservation Status
IUCN Red List: Least Concern. The species is widespread and adaptable, though localized populations face threats from water pollution and habitat destruction.
Cultural Significance
Often misunderstood and unfortunately killed by humans due to its resemblance to the Cottonmouth. In ecosystems, it serves as a vital mid-level predator that controls fish and amphibian populations.
Notable Features
The presence of vertical dark lines on the labial scales (edges of the mouth) is a key diagnostic feature of the genus Nerodia. This specimen shows the classic broken-band pattern characteristic of the sipedon species.