Cottonmouth snakes go by many names, but most people call them water moccasins. Its scientific name is Agkistrodon piscivorus (say that ten times fast), but that doesn’t roll off the tongue quite as smoothly as cottonmouth.
Highly dangerous and venomous, this species of pit viper lives in the southeastern United States. There’s a reason why hikers and nature lovers fear this snake: its bite can be fatal.
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What is a Cottonmouth, or Water Moccasin Snake?
The water moccasin is the only venomous water snake in North America, and they have a rather distinctive appearance (more on that soon). Those unlucky enough to live in the southeastern U.S. have been told since they were kids to watch out for these slithering death machines.
The only good news about these snakes is that they rarely bite humans. Like most other wild animals, they just want to eat and mind their own business.
But cottonmouths will attack if they feel threatened. If you’re paying attention to your surroundings, you may very well cross one’s path and wind up in a very dangerous situation.
We know this snake is dangerous, but where does it get its name? The nickname “cottonmouth” refers to the white interior of the snake’s mouth.
These snakes go by other names, too, including: stub-tail snake, black moccasin, mangrove rattler, gaper, snap jaw, water mamba, swamp lion, water pilot and trap jaw.
Its generic name comes from the Greek words ancistro, which means “hooked,” and odon, which means tooth. The Latin piscis translates to “fish” and voro “to eat.” So, this snake’s scientific name really means “hooked tooth fish eater.”
7 Basic Information about Cottonmouth Snake
1. Appearance and Size
Cottonmouths are large snakes. Adults can range between two and four feet long. Females are usually smaller than males. They have cat-like eyes and large jowls because of their venom glands.
The water moccasin has a distinctively triangular and blocky head, which helps passers-by identify them. Their necks are thin, and they have thick, muscular bodies. Their scales are ridged, and their colors vary from black to olive or dark brown. Some are yellow, while others are banded brown. A cottonmouth’s belly is paler than its back.
Young snakes have striking appearances with bold patterns, but their markings fade as they age. Juvenile snakes also have tails with bright yellow tips, which they use to lure in prey (like frogs) and strike.
Unfortunately, cottonmouths are often confused with harmless water snakes, like the northern water snake and the brown water snake. But if you pay attention to their appearance (without getting too close), you’ll notice some striking differences.
- Cottonmouths have vertical pupils, like cats. Non-venomous snakes have round pupils.
- Water moccasins have a triangular head. Harmless water snakes have elliptical-shaped, slender heads.
- Cottonmouths also have one row of scales after the anal plate, while non-venomous water snakes have two.
Even if you know what to look for when identifying water snakes, it’s stll better to leave alone any snake you find.
2. Diet and Feeding
Like the copperhead snake, rattlesnake and other pit vipers, the cottonmouth snake has pits in between their nostrils and eyes that can sense heat. These pits allow the snake to pick up on subtle changes in temperatures, so they can track their prey and strike.
Water moccasins can be seen anytime of year and anytime of day, but they prefer to hunt after dark.
Cottonmouths will eat just about anything near their watery homes, including fish, amphibians, small mammals, lizards, turtles and even small alligators. They’ll even eat other snakes – including small water moccasins.
Yes, these nasty snakes aren’t afraid to cannibalize their own kind (aren’t they sweet?).
When hunting frogs, the cottonmouth’s potent venom can cause complete lung collapse.
Cottonmouths prefer to ambush their land prey, inject them with venom, and chase them down when they’re subdued.
Most cottonmouths feed on fish. They corner their prey in shallow water, either against a log or the bank.
These snakes are opportunistic eaters and aren’t afraid to dine on carrion (gross). Researchers have observed these snakes feeding on fish heads that were thrown in the water by local fishermen.
3. Habits and Lifespan
Water moccasins are a type of water snake, so they naturally spend time in and around water. And as you may have guessed, these guys can swim pretty well.
Cottonmouths prefer to stay close to the water’s surface with their heads out.
4. Habitat and Distribution
The cottonmouth snake is found primarily in the southeastern United States. Their habitat stretches from Virginia to Florida and even eastern parts of Texas.
These snakes love to hang out in marshes, lakes, ponds, streams, drainage ditches and even swamps. When they’re not in the water, they can be found sunning themselves in fields, on top of rocks or on branches. Like other water snakes, cottonmouths love to bask in the sun because it keeps their body temperatures up.
5. Reproduction
Cottonmouth snakes mate in the spring months. Males show off by waving their tails around in hopes of luring females away from other potential mates. Courting becomes a game of who can wave and slither best.
And male cottonmouth snakes will fight each other for mating rights. But this is normal snake behavior for any species.
When females successfully mate with males, they carry their eggs inside their bodies until they’re ready to hatch. This makes them ovoviviparous creatures, which means their bodies incubate the eggs. The gestation period lasts three to four months.
A female cottonmouth gives birth to live babies every two to three years. Most litters have between ten and 20 baby snakes.
Baby cottonmouths are brightly colored and independent the moment they come into the world. Like most other snakes, mom and dad play no role in raising or caring for their young.
6. Hibernation
The habitat of cottonmouths range from Virginia down to sunny Florida. But for the snakes in Virginia, winter time is usually hibernation time.
Cottonmouths hibernate for several months in colder climates. But hibernation can be deadly for these creatures, albeit necessary. A lot of cottonmouths die during hibernation, and scientists believe this is the reason why they never migrate north of Virginia.
These snakes just aren’t cut out for the cold.
Water moccasins will hibernate in wooded hillsides, or bluffs, and they’ll stay in these stump holes until warmer weather comes around.
While they aren’t designed for the cold, water moccasins are never in a hurry to go into hibernation. They’re usually one of the last creatures to settle in for the winter and will often wait until the first heavy frost to hibernate.
7. Behaviors
Cottonmouths somehow developed a reputation for being an aggressive snake, but they rarely attack humans. But there is one difference between this species and non-venomous snakes: they will stand their ground.
Most non-venomous snakes run for the hills when they feel threatened, but the water moccasin will let you know this is his turf – and you better be the one running for the hills.
Water moccasins have a distinctive defense behavior, which will let you know that it’s time to leave.
- They coil their bodies and open their mouths wide to expose their white mouths.
Water moccasin’s have striking inner mouths because of their dark body colors. The bright white color serves as a warning to leave or face the consequences of their deadly bites.
Cottonmouth Snake Bites and Treatment
Cottonmouths have very potent bites. Their venom contains hemotoxins that actually break down blood cells to create an anti-coagulating effect. In simple terms, this means the venom prevents your blood from clotting.
While fatalities are rare, these snakes can kill you. The venom can cause hemorrhaging all throughout your circulatory system, or wherever the venom spreads.
A cottonmouth bite can cause:
- Temporary or permanent damage to muscles and tissue
- Loss of limbs, depending on the bite’s location
- Extreme pain
- Internal bleeding
If you’re ever bit by a cottonmouth snake, you need to seek medical attention immediately.
Cottonmouth Snake Conservation and Threats to Humans
Cottonmouth snakes are listed as “Least Concern” on IUCN’s Red List because of their large population and wide distribution. These venomous snakes are not likely to go extinct anytime soon.
But in the state of Indiana, the cottonmouth snake is considered an endangered species. Human encroachment and drainage of wetlands are the two biggest threats to these snakes.
Other Fun Facts about Cottonmouth Snake
There are Three Subspecies of Cottonmouth Snakes:
1. Florida Cottonmouth
The Florida cottonmouth lives in Florida as well as extreme southern Georgia. This subspecies can grown to be up to 74.5 inches long and weigh up to ten pounds. Florida cottonmouths have striking head markings, which usually include dark brown stripes bordered by thin and light lines.
2. Eastern Cottonmouth
The eastern cottonmouth can be found in southern Virginia, North Carolina, South Carolina and some parts of Georgia. This subspecies is typically between 20 and 48 inches in length, but it can grow to be 74.5 inches long. Eastern cottonmouths are usually darker in color with dark broad stripes along the face to disguise its eyes.
3. Western Cottonmouth
The western cottonmouth snake is the smallest of the three subspecies and is usually dark in color. Most are less than 36 inches long. Its coloring is similar to the eastern species. These snakes can be found in southeastern U.S. along the coast of Alabama, in central Texas, Oklahoma, Illinois, Oklahoma, Indiana and even southern Nebraska.
These Snakes Do Have Predators
The cottonmouth snake may be a venomous species, but that doesn’t stop other animals from preying on them.
Venomous water moccasins have many predators, including:
- Snapping turtles
- Horned owls
- American alligators
- Loggerhead shrikes
- Hawks
- Cranes
- Herons
- Egrets
The cottonmouth snake is a dangerous pit viper species, and should be treated with the utmost respect. If you’re unlucky enough to see one out in the wild, do not get close to these creatures. Turn and walk the other way.