The cottonmouth, also known as the water moccasin, is a large, venomous pit viper found in slow-moving water bodies across the southeastern United States. Its potent venom and semi-aquatic habits lead to frequent inquiries about its presence in areas outside its established range, including West Virginia. Formally named Agkistrodon piscivorus, the snake is known for its defensive display of opening its mouth to reveal a stark white interior, the source of its common name. The definitive answer is that the cottonmouth is not considered an established native species of West Virginia.
The Definitive Answer: Cottonmouth Status in West Virginia
The cottonmouth is not recognized by the West Virginia Division of Natural Resources (WV DNR) as part of the state’s native snake fauna. Of the approximately 20 species of snakes found in West Virginia, only two are venomous: the Timber Rattlesnake and the Northern Copperhead. There are no confirmed records of the cottonmouth or any venomous water snakes occurring within the state. The native range of Agkistrodon piscivorus extends only as far north as southeastern Virginia and west to parts of Kentucky and southern Illinois. West Virginia lies beyond this established distribution, making the state’s climate and habitat unsuitable for a stable population.
Any unconfirmed sightings are most likely misidentifications or, in extremely rare cases, individuals transported outside their natural range. The state’s official records do not include any verified, breeding populations of the cottonmouth. Residents should focus their attention on identifying the two confirmed venomous species: the Copperhead and the Timber Rattlesnake.
Accurate Identification: Distinguishing Cottonmouths from Look-Alikes
The persistent question about cottonmouths stems from the frequent misidentification of the common, non-venomous Northern Water Snake (Nerodia sipedon). This snake is abundant near water sources throughout the state, and its dark coloration and aquatic habits often lead people to mistakenly call it a “water moccasin.” Unlike the cottonmouth’s thick, heavy body and spade-shaped head, the Northern Water Snake has a more slender body and a head that is not distinctively wider than its neck.
A crucial identification detail is the shape of the pupils: cottonmouths, like all pit vipers, have vertical, elliptical pupils, similar to a cat’s eye, while the Northern Water Snake has round pupils. When swimming, the cottonmouth typically holds its entire body on the surface of the water, giving the appearance of “floating.” In contrast, the non-venomous water snake swims with most of its body submerged, with only its head visible when it stops moving.
The other venomous relative that can be confused with a cottonmouth is the Northern Copperhead (Agkistrodon contortrix), which is common throughout West Virginia. Both are pit vipers and share the characteristic triangular head shape and heat-sensing facial pits. The copperhead, however, is easily distinguished by its unique color pattern of reddish-brown or copper with dark, hourglass-shaped crossbands.
Juvenile cottonmouths are brighter in color with a strongly distinct pattern and possess a bright yellowish-green tail tip, which is used as a lure for prey. Adults tend to darken significantly with age, often becoming nearly uniform black, which can obscure the crossband pattern. Observing behavior can also help; while water snakes usually flee quickly, a cottonmouth may stand its ground and coil, displaying its pale mouth interior as a warning.
Encounter Safety and Reporting Protocol
When encountering any snake in West Virginia, the safest action is to simply leave it alone and maintain a distance. Snakes only strike if they feel threatened, cornered, or provoked, as retreat is their preferred defense mechanism. Never attempt to capture, handle, or kill a snake, as the majority of defensive bites occur during these actions.
If a bite does occur from a suspected venomous snake, first aid is limited to immediate transport to the nearest emergency department. The affected limb should be immobilized and kept below the level of the heart to slow the spread of any potential venom. Crucially, do not use outdated remedies like tourniquets, cutting the wound, or attempting to suck out the venom, as these actions can cause more harm.
For unusual snake sightings, particularly a suspected cottonmouth, West Virginia residents should contact the WV DNR or local wildlife authorities. High-quality photographic evidence is necessary for verification, but this should only be obtained from a safe distance. Reporting these sightings helps biologists accurately track the distribution of species and confirm the absence of non-native snakes.