Water moccasins, also known as cottonmouths (Agkistrodon piscivorus), are venomous snakes. They are not native to New York, found far to the south of the state’s borders.
Where Water Moccasins Are Found
Water moccasins primarily inhabit the southeastern United States, from central Texas eastward through the Gulf Coast states and north to southeastern Virginia. These semi-aquatic snakes prefer moist habitats such as swamps, marshes, slow-moving streams, and the shores of ponds and lakes. While comfortable in water, they can also be found in less moist environments like palmetto thickets or pine woods within their native range.
New York Snakes Mistaken for Moccasins
In New York, the snake most frequently misidentified as a water moccasin is the Northern Water Snake (Nerodia sipedon). This common non-venomous species is widespread across the state, often seen basking near or swimming in various freshwater bodies. Northern Water Snakes can grow to a considerable size, reaching up to 55 inches in length, and their robust bodies and dark coloration can contribute to the confusion. New York State is home to 17 snake species, but only three are venomous: the Timber Rattlesnake (Crotalus horridus), the Northern Copperhead (Agkistrodon contortrix), and the Eastern Massasauga Rattlesnake (Sistrurus catenatus). The Eastern Massasauga is the only one of New York’s venomous snakes that prefers wet habitats, but it is extremely rare and listed as an endangered species within the state, found in only two isolated wetland complexes.
How to Identify New York Water Snakes
Distinguishing New York’s native water snakes from water moccasins involves observing several key features. Water moccasins possess a broad, triangular head that is distinctly wider than their neck, and they have elliptical, cat-like pupils. They also have heat-sensing pits between their eyes and nostrils, a feature absent in non-venomous water snakes. Northern Water Snakes, conversely, have a more rounded head that blends smoothly into their body, along with round pupils.
When threatened, water moccasins may display the white interior of their mouth, giving them their “cottonmouth” name, and often swim with most of their body on the surface. In contrast, Northern Water Snakes typically swim with only their head visible above the water line. While Northern Water Snakes can flatten their bodies and heads to appear larger when feeling threatened, their overall body proportion remains more slender compared to the thick, heavy build of a water moccasin. Their coloration varies from pale grey to dark brown, often with reddish-brown to black bands or blotches that can become very dark in older individuals.
What to Do When You See a Snake in New York
Encountering any snake in New York warrants a cautious approach. Observe the snake from a safe distance, at least six feet away. Avoid attempting to handle, harass, or harm it. Most snakes prefer to avoid human interaction and will move away if given space.
If a snake is in an undesirable location, such as inside a home or garage, contact local wildlife control services or the Department of Environmental Conservation (DEC) for safe removal. All native snakes contribute to the ecosystem, often by controlling rodent populations.