Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Most of the eastern and central United States, from southern Ontario and Quebec in Canada, south to Louisiana and west to Colorado.
Look up Common Watersnake in the Snake Encyclopedia →Venomous Status
Non-venomous
Danger Level
Harmless; however, they are highly defensive and will bite repeatedly and Musk if handled, but the bites are not medically significant for humans.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
IUCN Status: Least Concern. Populations are stable across most of their range, though they are often killed due to confusion with venomous cottonmouths.
Physical Description
Heavy-bodied with strongly keeled scales. Coloration consists of dark crossbands near the head that break into alternating dorsal and lateral blotches further down the body. Base color varies from tan to grey, with dark brown or reddish-brown markings. Pupils are round.
Size & Dimensions
Typically 61–107 cm (24–42 inches). The specimen in the image appears to be a sub-adult or adult of approximately 60-80 cm based on the surrounding vegetation.
Habitat
Primarily freshwater habitats including ponds, lakes, rivers, streams, and marshes. Often found basking on rocks, logs, or overhanging vegetation. Frequently near the water's edge.
Behavior & Temperament
Mainly diurnal but hunt at night during warmer months. They are very defensive when threatened, often flattening their bodies and heads to look larger and biting vigorously. They also release a foul-smelling musk.
Diet & Feeding
Primarily piscivorous (fish) and carnivorous (amphibians). They use active foraging and ambush techniques to catch prey, which they swallow alive without constriction.
Reproduction
Viviparous (gives birth to live young). Mating occurs in spring, and females typically give birth to 15–30 young in late summer or early autumn.
Venom Profile
Non-venomous - no medically significant venom.
Look-alikes
Commonly confused with the Northern Cottonmouth (Agkistrodon piscivorus). Distinguishable by round pupils (slit-like in Cottonmouth), lack of a heat-sensing pit, and vertical labial bars on the lips which the Cottonmouth lacks.
Conservation Status
IUCN Status: Least Concern. Populations are stable across most of their range, though they are often killed due to confusion with venomous cottonmouths.
Cultural Significance
Crucial for controlling fish and amphibian populations in local ecosystems. Frequently encountered by fishermen and often misunderstood due to their defensive nature and resemblance to vipers.
Notable Features
Excellent swimmers and divers that can stay submerged for up to 90 minutes. They have anticoagulant properties in their saliva which can cause bites to bleed more than expected.