Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Found throughout central and eastern North America, from Southern Ontario and Quebec (Canada) down through the eastern United States to North Carolina, and as far west as Colorado and Oklahoma.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous
Danger Level
Harmless/Low Risk. While they are non-venomous, they are famously defensive and will bite readily if handled, which can cause bleeding due to anticoagulants in their saliva, but no long-term medical harm.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
IUCN Red List: Least Concern. Generally abundant throughout its range, though sometimes mistaken for the venomous Cottonmouth and killed.
Physical Description
Medium-sized snake with a thick body and keeled scales. Coloration typically involves brownish, grayish, or reddish-brown crossbands on the neck 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 photo appears to be a juvenile or sub-adult based on the vibrant pattern (which darkens with age). Adults typically range from 60 to 120 cm (24 to 42 inches) in length.
Habitat
Highly semi-aquatic. Prefers slow-moving or standing water such as lakes, ponds, marshes, rivers, and canals, often found basking on rocks or logs near the water's edge.
Behavior & Temperament
Diurnal and crepuscular, often active at night during hot weather. Known for a very defensive temperament; they will flatten their bodies to appear larger, release a foul-smelling musk, and strike repeatedly if cornered or touched.
Diet & Feeding
Primarily piscivorous and carnivorous, feeding on various species of fish and amphibians (frogs, toads, tadpoles). They are active foragers that hunt along the water's edge or underwater.
Reproduction
Viviparous (gives birth to live young). Mating occurs in spring, and litters of 15 to 30 young (sometimes more) are typically born between August and October.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Frequently confused with the venomous Cottonmouth (Agkistrodon piscivorus). Distinct differences include the Cottonmouth's vertical pupils, heat-sensing pits, and a dark band through the eye, whereas the Watersnake has round pupils and lack of pits.
Conservation Status
IUCN Red List: Least Concern. Generally abundant throughout its range, though sometimes mistaken for the venomous Cottonmouth and killed.
Cultural Significance
Crucial for wetland ecosystem health, acting as both a predator of fish/amphibians and prey for larger birds and mammals. They help control overpopulated fish species in small ponds.
Notable Features
Often found in swimming pools or skimmer baskets (as seen in the image) when searching for water or prey, leading to frequent human encounters. Their scales are heavily keeled, giving them a rough texture.