The water moccasin belongs to the Crotalidae (pit viper) family and is among the most venomous snakes in the world. A bite from this snake can be fatal. Because of this, people fear them a great deal, but being able to spot one is actually the best protection you have.
How to Identify a Water Moccasin
This snake is a type of cottonmouth snake. Cottonmouths get their name from the habit of opening their mouths wide to show the bright white lining inside, a warning signal aimed at anything that comes too close.
Here are the key features to look for when trying to identify this snake.
Habitat Clues
Water moccasins live mostly near freshwater habitats, rivers, wetlands with heavy vegetation, cypress swamps, and floodplains. Sometimes they do wander away from the water. You might spot one near a drying pool where it is hunting for fish or amphibians.
This snake turns up most often in Florida, and has been seen many times in Texas and Alabama. Though it is a North American species, it may be found in other southeastern states too.
Body Shape
One quick way to tell a water moccasin apart from a harmless water snake is body shape. The water moccasin has a heavy, thick body, while harmless water snakes have a slender, tapered build. A full-grown water moccasin can be about 4 to 6 feet long.
Head, Neck, and Eyes
The water moccasin has a triangular-shaped head, and its neck is noticeably narrower than its head. These are classic pit viper traits.
A key detail: there is a small heat-sensing pit between the eye and nostril on each side of the head, this gives pit vipers their name and helps them detect warm-blooded prey in the dark.
The eye pupil is vertical (a narrow slit), unlike harmless water snakes, which have round pupils. If you can safely see the eye, this is one of the most reliable identification signs.
Water moccasins also carry their heads at roughly a 45-degree angle, a characteristic resting posture that is easy to recognize once you have seen it.
Water Moccasin ID Quiz
5 quick questions. Could you spot one in the wild?
Color and Pattern
Adult and young water moccasins look quite different. Young ones have red-brown crossband patterns and yellowish tails. The crossband pattern is easy to see on juveniles.
In adults, the same crossband or diamond-shaped pattern is still visible, but shows up in greenish or tan tones and can be harder to see. The overall body color ranges from dark olive to almost black.
Frequently Asked Questions
What family does the water moccasin belong to?
Crotalidae (pit vipers)
How long do water moccasins grow?
4 to 6 feet for adults
Why is it called a cottonmouth?
It gets the name from its habit of displaying the bright white lining inside its mouth as a warning.
What should you do if bitten by a water moccasin?
Call 911 immediately and get to a hospital. Treatment involves antivenin, antibiotics, and often intravenous fluids.
Where are water moccasins found?
Mostly in the southeastern United States (especially Florida, Texas, and Alabama) near freshwater wetlands, swamps, and floodplains.
The Defense Display
The most dramatic identification clue is the defense display. When threatened, the water moccasin coils up its heavy body and holds its mouth wide open, showing the brilliant white lining inside. This is how it earned the nickname "cottonmouth." If you see a thick-bodied snake doing this near water, back away slowly.
Water Moccasin Bite and Treatment
If you can identify the snake, do not disturb it, it may bite in self-defense. Here is what you need to know about the bite and how it is treated.
How the Venom Works
The venom glands sit around the area where the jaws join. When the snake bites, muscles squeeze those glands and push the venom into the wound. The venom destroys blood cells, which reduces the blood's ability to clot and can lead to hemorrhage in affected body parts.
Sometimes a water moccasin gives a "dry bite", a bite with little or no venom released. But you should never assume a bite is dry. Even a dry bite can become infected, and symptoms of envenomation may not appear immediately. An untreated bite can be fatal.
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Treatment
Call 911 right away and get immediate medical help. Treatment involves antivenin and antibiotics. Intravenous fluids are often needed too. You can keep a basic first-aid kit for snakebites at home for emergencies, but hospital treatment is always required; first aid is only a bridge.
If you spot a water moccasin, do not try to handle or remove it yourself. Contact snake control authorities. Keep their number somewhere easy to find, a sticky note on the fridge works well.
Fun fact for today!The water moccasin gets its nickname "cottonmouth" from the brilliant white lining inside its mouth, shown as a warning to anything that gets too close!