Common Watersnake (Midland or Northern subspecies)
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Natural to North America, ranging from southern Ontario and Quebec in Canada throughout most of the eastern and central United States, as far south as North Carolina and as far west as Colorado.
Look up Common Watersnake (Midland or Northern subspecies) in the Snake Encyclopedia →Venomous Status
Non-venomous (Aglyphous- lacking specialized fangs)
Danger Level
Low Risk (Harmless). While they are non-venomous, they are famously defensive and will bite readily if handled or cornered. Bites may bleed more than expected due to anticoagulants.
Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
IUCN Red List: Least Concern. Generally abundant, though they face threats from habitat destruction and persecution by humans who mistake them for venomous species.
Physical Description
Heavy-bodied snake with strongly keeled (rough) scales. Coloration ranges from grayish-brown to reddish-brown with dark crossbands near the head that break into alternating blotches on the back and sides toward the tail. The head is flat and slightly wider than the neck, and the pupils are round.
Size & Dimensions
Specimen appears to be an adult, approximately 24-36 inches. Species range is typically 24-42 inches (61-107 cm); the record is approximately 59 inches.
Habitat
Semiaquatic, found in or near freshwater sources such as lakes, ponds, rivers, marshes, and canals. Often seen basking on rocks or logs near the water's edge.
Behavior & Temperament
Diurnal and crepuscular; active during the day and twilight. Very defensive; when threatened, they flatten their bodies and heads to appear larger, release a foul-smelling musk, and strike repeatedly.
Diet & Feeding
Carnivorous active foragers and ambush hunters. Primary diet consists of fish, frogs, salamanders, and occasionally small mammals or large insects.
Reproduction
Viviparous (gives birth to live young). Mating occurs in spring, and females give birth to 15-30 young in late summer or early autumn.
Venom Profile
Non-venomous - no medically significant venom. However, their saliva contains a mild anticoagulant to facilitate prey ingestion.
Look-alikes
Often confused with the venomous Northern Cottonmouth (Agkistrodon piscivorus). Distinct from Cottonmouths by their 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. Generally abundant, though they face threats from habitat destruction and persecution by humans who mistake them for venomous species.
Cultural Significance
Ecologically vital as both a predator of fish/amphibians and prey for birds and larger mammals. Frequently misunderstood and killed due to its resemblance to the Cottonmouth/Moccasin.
Notable Features
Highly adapted for an aquatic lifestyle, they can remain submerged for extended periods and are excellent swimmers. Their keeled scales give them a very 'rough' appearance compared to smooth-scaled colubrids.