The Water Moccasin, scientifically known as the Cottonmouth (Agkistrodon piscivorus), is a large, highly venomous, semiaquatic snake. This pit viper spends significant time in and around water. Its common name comes from its defensive display of flashing the white interior of its mouth. Due to its potent venom and preference for watery habitats, many people are concerned about its presence in West Virginia.
Water Moccasin Range
The Water Moccasin is not native to or established in West Virginia. Herpetological surveys and distribution maps confirm that the state lies outside the natural geographic range of Agkistrodon piscivorus. The northern boundary of the Cottonmouth’s territory extends only as far north as the southeastern coastal plain of Virginia, typically around the Great Dismal Swamp or the James River.
The absence of the species is largely due to environmental factors, specifically temperature and elevation. Water Moccasins thrive in the warm, slow-moving, and often swampy lowland waters of the deep southeastern United States. West Virginia’s higher elevations and cooler climate, characterized by many swift-moving, rocky mountain streams, do not provide the preferred habitat for this species. There are no confirmed records of any venomous water snake species occurring within the state’s borders.
Common Water Snakes Mistaken for Moccasins
While the venomous Cottonmouth is absent, West Virginia is home to the Northern Water Snake (Nerodia sipedon). This non-venomous snake is responsible for nearly all reported “Water Moccasin” sightings in the state due to its aquatic lifestyle and defensive behavior. The Northern Water Snake is a robust, large snake that lives in virtually all freshwater habitats, including ponds, lakes, streams, and rivers.
It frequently basks on logs, rocks, or overhanging branches near the water. When disturbed or threatened, the Northern Water Snake will flatten its head and body, making its head appear triangular, which mimics the broad, spade-shaped head of a pit viper. If handled, it will strike repeatedly and bite, though its bite is not venomous, and it often releases a foul-smelling musk to deter predators.
Distinguishing Nerodia sipedon from the true Cottonmouth involves several features. Northern Water Snakes have round pupils and heavily keeled scales, giving them a rough appearance. The Cottonmouth, being a pit viper, possesses elliptical, vertical pupils and a distinctive heat-sensing pit between its eye and nostril, which the water snake lacks. Additionally, the Northern Water Snake’s dark crossbands often become almost entirely black as the snake ages, making it appear uniformly dark and contributing to its misidentification.
The Actual Venomous Snakes Found in West Virginia
Although the Water Moccasin is not present, West Virginia is home to two species of venomous pit vipers: the Timber Rattlesnake (Crotalus horridus) and the Eastern Copperhead (Agkistrodon contortrix). The Eastern Copperhead is the more commonly encountered of the two and is found throughout the state in deciduous forests and woodlands. It is identified by its stout body and the characteristic hourglass-shaped bands of rich reddish-brown coloration that narrow across the snake’s back.
The Copperhead is in the same genus as the Cottonmouth (Agkistrodon), but it is primarily a terrestrial species. Timber Rattlesnakes are the state’s other venomous species, preferring remote, rocky, mountainous terrain, especially around rock outcroppings. This snake is easily recognized by its heavy body, dark chevron-shaped markings, and the distinct segmented rattle at the end of its tail.
Both of these snakes are ambush predators and will strike defensively if they are directly threatened or accidentally stepped on. When hiking or spending time outdoors, observe any snake from a distance and leave it undisturbed. While the vast majority of snakes in the state are harmless, maintaining a respectful distance prevents defensive bites from the two venomous species that reside there.