Water snakes, primarily belonging to the non-venomous Nerodia genus in North America, commonly inhabit lakes, rivers, and marshes. They are highly adapted to aquatic environments, where they hunt fish and amphibians. Water snakes will bite if they feel they are in danger or are being handled. This bite is purely a defensive action, which is key to understanding the risks and necessary precautions when encountering these reptiles.
Differentiating Water Snakes from Cottonmouths
Distinguishing a common water snake from the venomous Cottonmouth or Water Moccasin is essential for safety. Cottonmouths are pit vipers with a distinctly triangular head shape that is broader than their neck, a feature water snakes often mimic defensively.
A more reliable visual cue is the pupil: Cottonmouths have elliptical, vertical pupils, while non-venomous water snakes have round pupils. Cottonmouths also have a prominent angular ridge above their eyes that partially obscures them. Water snakes lack this ridge, allowing the eye to be fully visible from above.
Behaviorally, a threatened Cottonmouth performs a warning display by opening its mouth wide to reveal a stark white interior, the origin of its common name. Water snakes are defensive and typically try to flee, but may flatten their bodies and hiss before striking.
Understanding Defensive Biting Behavior
Bites from water snakes occur almost exclusively as a last resort when the animal perceives a threat and cannot escape. They are not aggressive toward humans; they are reacting to being cornered, stepped on, or handled. Their primary instinct when approached is to retreat into the water or dense vegetation.
The bite is characterized by numerous small, superficial puncture wounds or lacerations from their many small, sharp teeth. Unlike the distinct pair of fang marks left by a pit viper, a water snake bite resembles a small scratch or rake mark. Water snake saliva contains a mild anticoagulant, which can cause the wound to bleed more profusely than expected.
Immediate Care for Non-Venomous Bites
If the bite is confirmed to be from a non-venomous water snake, the primary concern is preventing infection. The initial step involves gently washing the wound thoroughly with mild soap and warm water for several minutes. This removes any bacteria introduced from the snake’s mouth or the environment.
After cleaning, apply a topical antiseptic or an antibiotic ointment to reduce the risk of bacterial contamination. The treated wound should then be covered loosely with a clean, dry bandage or sterile gauze.
The wound should be monitored closely for the next few days for signs of infection. These signs include increasing redness, notable swelling, warmth, or the presence of pus. If any of these signs appear, or if the wound is deep or the snake’s identity is uncertain, seek medical attention immediately, as a tetanus booster may be necessary.
Emergency Protocol for Suspected Venomous Bites
If there is any doubt about the snake’s identity, or if the bite shows the two distinct puncture marks of a pit viper, call 911 or your local emergency number immediately. While waiting for emergency medical services, the individual should remain calm and still to help slow the circulation of any potential venom. Remove any jewelry, watches, or tight clothing from the affected limb, as swelling often occurs rapidly.
The bitten limb should be immobilized and kept at approximately the same level as the heart. Avoid outdated first aid methods, including applying a tourniquet, cutting the wound, or attempting to suck out the venom, as these actions cause harm and are not effective. Do not apply ice or water to the wound, and do not consume caffeine or alcohol.