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 east to the Atlantic coast.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous (Aglyphous - lacks specialized venom-delivery fangs).
Danger Level
Harmless. While they are often defensive and may bite if handled, they pose no toxic threat to humans. The saliva contains mild anticoagulants to aid in prey ingestion but is not dangerous to people.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
Least Concern (IUCN). Extremely common and adaptable, though often killed by humans who mistake them for venomous snakes.
Physical Description
The specimen shows a heavy-bodied appearance with grayish-brown base coloration and darker transverse bands that often break into blotches down the back. Scales are heavily keeled (rough). The head is slightly distinct from the neck with large eyes and round pupils.
Size & Dimensions
This specimen appears to be an adult, approximately 24-30 inches (60-76 cm). The species typically ranges from 24 to 42 inches, with a maximum recorded length near 53 inches.
Habitat
Found in various freshwater habitats including rivers, lakes, ponds, marshes, and ditches. This specimen is in a garden pond, which is a common urban/suburban microhabitat for this species.
Behavior & Temperament
Diurnal and crepuscular; active baskers. When threatened, they are known for a feisty temperament, often flattening their bodies to appear larger, musking, and biting repeatedly if cornered or grabbed.
Diet & Feeding
Active forager specializing in aquatic prey. Diet consists primarily of fish (as seen by its interest in the goldfish/koi in the pond) and amphibians like frogs and salamanders. They do not constrict, but swallow prey alive.
Reproduction
Viviparous (gives birth to live young). Breeding occurs in spring, with litters ranging from 15 to 30 young (sometimes more) born in late summer or early autumn.
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 labial scales with vertical black lines (barring) along the mouth.
Conservation Status
Least Concern (IUCN). Extremely common and adaptable, though often killed by humans who mistake them for venomous snakes.
Cultural Significance
Important ecological role as a mid-level predator in aquatic ecosystems. Frequently serves as a 'misunderstood' species, acting as a primary subject for education on snake identification and conservation.
Notable Features
Highly aquatic nature, able to remain submerged for extended periods. Their scales are very rough to the touch due to strong keeling, which helps them maneuver in wet, slippery environments.