Banded water snakes are frequently encountered in aquatic environments across their range. Their presence often leads to questions about their potential danger due to their appearance and habitat. This article aims to clarify the nature of banded water snakes, provide practical identification information, and explain how to differentiate them from other snakes that might share similar habitats.
The Non-Venomous Nature of Banded Water Snakes
Banded water snakes, scientifically known as Nerodia fasciata, are entirely non-venomous reptiles, lacking venom glands and fangs necessary to inject toxins. They pose no venomous threat to humans. Their presence in freshwater habitats, such as ponds, lakes, streams, and marshes, often causes them to be mistaken for venomous species like the cottonmouth.
Despite being harmless, banded water snakes can exhibit defensive behaviors when they feel threatened. They are typically shy and prefer to escape when approached. If cornered or handled, they may flatten their body and head to appear larger, strike repeatedly, or release a foul-smelling musk as a deterrent. These behaviors are defensive reactions, not acts of aggression, and their bite is not medically significant beyond a superficial wound.
Key Identification Features
Banded water snakes have several distinct physical characteristics. Their body is generally heavy and robust, with patterns that vary widely. The crossbands on their body can range in color from reddish to brown or black, and these bands often appear rectangular. These patterns may become less distinct or darken with age, making older individuals appear almost uniformly dark.
Their head is relatively narrow, not significantly wider than their neck. Their pupils are round. Banded water snakes also possess keeled scales, meaning each scale has a raised ridge along its center, giving the snake a rough, matte texture rather than a smooth, shiny appearance.
Distinguishing Them From Venomous Look-Alikes
Differentiating banded water snakes from venomous species, particularly the cottonmouth (Agkistrodon piscivorus), is important for safety. Cottonmouths, also known as water moccasins, are venomous snakes that share similar aquatic habitats. One notable difference is the cottonmouth’s head, which is distinctly broad and triangular, appearing much wider than its neck.
Cottonmouths also have vertical, elliptical pupils, often described as “cat-like,” in contrast to the round pupils of banded water snakes. Another distinguishing feature of cottonmouths is the presence of heat-sensing pits located between their nostrils and eyes. Their bodies are generally much thicker and more robust than those of banded water snakes, especially in mature adults.
Behavioral cues also help in differentiation. Cottonmouths are known for their defensive display of “gaping,” where they open their mouth wide to reveal a stark white interior. When swimming, cottonmouths often keep their entire body afloat on the water’s surface, while banded water snakes typically swim with only their head visible above the water.
Safe Practices When Encountering Water Snakes
Encountering any snake in its natural habitat warrants a cautious approach, regardless of its perceived venomous status. The most important practice is to observe the snake from a safe distance, allowing it to move away undisturbed. Approaching or attempting to interact with any snake can provoke a defensive reaction.
It is always advisable to avoid handling or harassing any snake, as this is when bites are most likely to occur. Snakes generally prefer to avoid human interaction and will only strike if they feel threatened or cornered.
If a snake is found in an undesirable location, such as inside a home or building, it is best to contact local animal control or a wildlife removal service. These professionals have the expertise to safely relocate the animal without harm to themselves or the snake. In the rare event of a snake bite, seeking immediate medical attention is always recommended.