Cottonmouths have a fearsome reputation as aggressive and dangerous snakes. Many harmless water snakes are killed when people mistake them for water moccasins. However, while cottonmouths do have venom glands, their reputation as a lethal snake is not entirely grounded.
Cottonmouth snakes (water moccasins) are venomous snakes. However, their bites rarely kill humans. Cottonmouths are found near or in bodies of water in the southeastern United States. These snakes are known for standing their ground when threatened, but they will only bite if provoked. Antivenom can cure a cottonmouth bite.
Here you will learn about the traits of a cottonmouth snake, so that you can identify one if you come across it in the wild. Then you will find out more about cottonmouth venom and the consequences of getting bitten.
Can a Water Moccasin Kill a Human?
The cottonmouth snake, Agkistrodon piscivorus, is the only venomous water snake in North America. It is a pit viper, related to rattlesnakes and copperheads. Cottonmouth snakes are also known as water moccasins, black moccasins, snap jaws, swamp lions, and water pilots.
While their bites are dangerous, it is very rare for humans to be bitten by cottonmouths. It is even rarer for a human to die from a cottonmouth bite. Still, cottonmouth bites can have harmful effects on the human body.
How To Identify a Cottonmouth
Cottonmouth snakes have a distinctive triangular, blocky shape to their head. This head is distinct from its thinner neck, unlike many snakes that do not have any distinctive neck. They also have a thick body compared to other, more slender snakes.
Cottonmouths range between 2 and 4 feet long. According to the Journal of Zoology, male cottonmouths are larger than females, and they also hunt larger prey than the female cottonmouths.
Scale Colors And Patterns
Cottonmouth snakes have a stout body covered in keeled scales. These scales can be dark brown, olive, or black in color.
The snake’s belly scales are paler than the dorsal scales. On the face, dark stripes line each nostril, and its snout is paler than the rest of the face.
Juvenile cottonmouths have a different appearance than adult snakes. They have brighter coloration, including a bright yellow tail tip they can use to lure in prey. This yellow tail tip will fade as the snake ages.
Juvenile s also have lighter brown bands across their body which will fade as they age. The closer to the tail the bands are, the darker the bands get. Occasionally you will see these crossbands on an adult cottonmouth as well.
The name “cottonmouth” comes from the bright white color of the inside of the snake’s mouth. When threatened, the snake will open its mouth wide, letting you see its unique coloring.
How To Spot a Venomous Water Snake
Many nonvenomous water snakes are killed every year because people mistake them for cottonmouths. However, most water snakes in North America are not venomous.
You can tell the difference between a venomous and nonvenomous water snake by looking at its head. Cottonmouths have vertical pupils, similar to a cat’s pupils, while nonvenomous water snake has round pupils.
Also, nonvenomous snakes have a much more slender, oval-like head shape than a cottonmouth’s flattened triangle. Sometimes a nonvenomous water snake will flatten out its head in response to a threat.
However, this does not mean that the snake is venomous. Rather, the snake is trying to mimic the appearance and behavior of a venomous snake to chase you away.
Where Do Cottonmouth Snakes Live?
These snakes are semiaquatic, and so you will find them both in water and on land. Water mocassins live all throughout the southeastern United States, as far north as Virginia, as far south as Florida, and as far west as Texas. You will also find them in various midwestern states as well, including Illinois, Indiana, and Tennessee.
Cottonmouths prefer an environment with a temperate climate. You may find one in a wide range of bodies of water, including marshes, swamps, ponds, lakes, streams, and drainage ditches.
These snakes enjoy swimming and sunning themselves on logs, stones, or branches near the edge of the water. When cottonmouth snakes swim, their entire body is visible on the surface of the water. When they are on land, these snakes will often hide under branches and logs on the ground.
According to the Journal of Herpetology, a cottonmouth’s territory is a relatively linear area along the edge of a body of water such as a stream. Larger individual snakes tend to have larger territories, but they do not roam far from the water.
Cottonmouths prefer freshwater sources, though they are occasionally found in saltwater marshes or lakes. Occasionally they will live in more urban areas where there is a good water source to live near.
Are Cottonmouth Snakes Venomous?
Cottonmouths are venomous snakes. Their venom can harm humans and their bite requires medical attention. However, deaths from cottonmouth bites are extremely rare.
Cottonmouth Snake Venom
The venom in a cottonmouth snake’s bite is mainly composed of hemotoxins. Hemotoxins prevent the blood from coagulating. Ordinarily, when you get a cut on your skin, your blood cells will clot themselves to stop the bleeding. Cottonmouth venom keeps that clotting from happening.
As the venom spreads through the victim’s circulatory system, so does the inability to clot blood. This leads to hemorrhaging, internal bleeding, and other painful consequences.
Other consequences of envenomation are extreme pain and swelling in the area of the bite. Later symptoms are necrosis or cell death around the bite, damage to tissue and muscle in the affected limb, and sometimes gastrointestinal problems from internal bleeding.
In the most extreme cases, depending on where the cottonmouth bit its victim, loss of extremities can potentially occur. The sooner you get to a doctor, the better prognosis you will have. Most cottonmouth snake bites can be treated without these extreme consequences.
Cottonmouth Snake Teeth
Pit vipers, like cottonmouths, have proteroglyphous teeth. This kind of snake teeth is the one that you imagine when you think of snake fangs. The cottonmouth has two curved fangs at the front of its mouth. These fangs are hollow, allowing them to channel and inject venom into their victim.
According to Copeia, the cottonmouth’s jaw has two quadrato-mandibular joints which allow the snake to wrap its mouth around its prey. The snake uses these joints to alternately move the sides of its jaw, advancing its mouth over the prey until the snake can swallow it.
Since humans are much bigger than a cottonmouth’s usual prey, it will attempt to swallow you. If it bites you, the cottonmouth may attempt to hold on with its teeth in order to successfully inject its venom. These snakes let go of their prey after a bite.
Severe envenomation rarely occurs when a cottonmouth snake bites a human. However, there is an increased risk of severe health problems the longer you wait to get medical attention for the bite. Younger children are also at greater risk for consequences of envenomation.
Cottonmouths do not always inject their victims with venom. It is possible to get a “dry bite” in which no venom was injected at all. Still, if you are bitten, be sure to go to the doctor as soon as you can.
Are Cottonmouth Snakes Aggressive?
Cottonmouth snakes have a reputation for being aggressive. This is not entirely true. These snakes do not go out of their way to attack or harm humans. In fact, it is rare for a cottonmouth to bite a human.
These snakes only attack when they feel threatened. Unless you actually physically touch the snake with your hand or foot, it is unlikely to bite you. The vast majority of cottonmouth bites come from when someone accidentally steps on a cottonmouth snake with a bare foot.
While they are not overly aggressive, cottonmouths are a little more courageous than most snakes when facing a threat. Most snakes, including water snakes, will flee from threats as their first instinct.
A cottonmouth, however, will stand its ground. The cottonmouth will coil its body and open its mouth, displaying the white lining. This is a warning to its predator to stay away and avoid a painful bite.
What To Do When Bitten
Fatalities from cottonmouth snake bites are very rare. Antivenin is commonly available to counteract the venom’s effects. Here are some tips for what to do, and not do, if you are bitten by a cottonmouth.
Do your best to stay calm, even if you are afraid of snakes. If you let yourself panic, then you won’t be thinking straight about what to do next.
Also, an increased heart rate from the panic can speed up the venom’s progress through your bloodstream, increasing its side effects.
Don’t Suck Out The Venom
In Western movies, people often respond to snakebites by using their mouth to suck the venom out of the bite. In real life, this will not work.
Putting your mouth to an open wound is more likely to cause an infection than it is to draw out any venom.
Remember The Snake’s Physical Appearance
Do not try to capture the snake. Even a dead snake can accidentally cause another bite or increased envenomation. The doctor does not need to have the snake physically in the office with them in order to help you.
What they do need to know is what kind of snake you found. Make a mental note of the snake’s traits – how big it was, what color was it, and if it had any distinctive patterns. This will help the doctor identify the cottonmouth snake and apply the correct antivenin.
In order to prevent permanent harm from a cottonmouth bite, you need help from a medical professional. The doctor can figure out if you were injected with venom and administer treatment as necessary.
A cottonmouth snake is not likely to kill you, though its bite can still cause you harm. Knowing more about cottonmouths, how to avoid them, and the effects of their venom can help you stay safe from cottonmouth snakebites.