Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Common across North America, ranging from southern Ontario and Quebec in Canada throughout the eastern and central United States, as far south as 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; although they are non-venomous, they are famously defensive and will bite repeatedly if handled, often producing an anticoagulant that causes bites to bleed profusely.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
IUCN List: Least Concern. Generally abundant, though populations face localized threats from habitat destruction and persecution by humans.
Physical Description
Heavy-bodied snake with highly keeled scales. Coloration is typically gray to dark brown with darker crossbands or blotches that are wider than the spaces between them. Bands start at the head and often break into alternating blotches down the back. Belly is usually lighter with reddish-brown half-moons. Pupils are round.
Size & Dimensions
The specimen in the image appears to be a sub-adult or adult, roughly 24 to 36 inches in length. Species typical size range is 24 to 42 inches (60-106 cm), with a maximum recorded length of 59 inches.
Habitat
Found in almost any freshwater habitat including lakes, rivers, ponds, marshes, and canals. They prefer slow-moving or still water with ample vegetation and basking spots like rocks or logs.
Behavior & Temperament
Highly defensive when Cornered. They are primarily diurnal but hunt at night during summer. Defensive displays include flattening the head and body to appear larger, striking, and releasing a foul-smelling musk and feces from the cloaca.
Diet & Feeding
Primarily piscivorous and carnivorous, feeding on various fish species, frogs, salamanders, and occasionally small mammals or birds. They are active foragers that search through debris or underwater vegetation for prey.
Reproduction
Viviparous (gives birth to live young). Breeding occurs in the spring, and females give birth to 15-30 young between August and October.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Commonly confused with the venomous Northern Cottonmouth (Agkistrodon piscivorus). Distinct differences include round pupils (vertically elliptical in cottonmouths), labial scales with vertical black lines (absent in cottonmouths), and a more slender head that doesn't have the deep heat-sensing pits of vipers.
Conservation Status
IUCN List: Least Concern. Generally abundant, though populations face localized threats from habitat destruction and persecution by humans.
Cultural Significance
Often misunderstood and killed due to its resemblance to venomous species. Ecologically, they are vital for controlling fish and amphibian populations and serve as a food source for larger predators like herons and raccoons.
Notable Features
Notable for their ability to dive and stay submerged for extended periods. Their scales are very rough (keeled), which helps in gripping slippery aquatic prey like fish.