Warm weather brings out the paddlers, hikers and campers in Missouri — and also the state's four venomous snakes.
Now is the time to get to know the slithery critters that are best observed from a distance so you don't end up at a hospital ER with a nasty snake bite. Missouri technically has five venomous snakes, but one of them, the diminutive massasauga rattler, has mostly vanished from its far northern Missouri range.
Ever wonder why this hefty venomous snake is often called a water moccasin?
"A cottonmouth swims with most of its body on top of the water, and when you see one swimming that way, it's like it's walking on the water," said John Miller, snake expert and manager of Shepherd of the Hills Conservation Center. "It got its nickname 'water moccasin' because of the way it seems to walk on the water."
More commonly known as a cottonmouth, it gets that name from the defensive head-back, mouth-wide-open posture that shows the snake's white mouth and sometimes its fangs when confronted by people. Cottonmouths are known to exist in the southern third of Missouri, mostly along waterways where they dine on fish, frogs, small mammals and other small creatures, Miller said.
"We do see them in the Ozarks on smaller remote streams like Flat Creek, the James River, and definitely on the Buffalo River in Arkansas," Miller said. "I've seen a couple on Table Rock Lake way back in a cove. The snake was doing its best job trying to float away from us."
Miller said of all the venomous snakes in Missouri, cottonmouths are the ones most often misidentified. People see a large snake sunning on a log in the river and assume it's a cottonmouth, he said. Most likely it's a nonvenomous water snake.
"Water snakes typically swim with their bodies under water, which is one way to identify them," Miller said. "Cottonmouths can swim under water if they're frightened, but mostly you'll see them on top of the surface."
Cottonmouths can grow up to 3 feet long, and their thick bodies make them a formidable-looking snake. Juveniles often have reddish or rust-colored splotches of color on their backs, but adults tend to be darker and almost olive green.
Miller said cottonmouths are not naturally aggressive, "but they will stand their ground and open their mouths as a warning that it wants you to see it and to stay back."
"Think about it. A man is 80 times its size, so it wants to protect itself," Miller said.
A common myth is that cottonmouths will chase a person. Miller said that's not true, but adds an asterisk.
"Water snakes can be unpredictable and will escape to a place that is safe, and they'll go to that safe spot time and time again," he said. "If you're on the riverbank, their safe spot might be behind you. If you run, it may appear the snake is chasing you, when it's only trying to get to its safe place."
A bite by a cottonmouth can be serious, though there is only one documented instance in Missouri where a cottonmouth bite contributed to a person's death. That happened in 2015 when a Nixa man was bitten while wading in the James River and refused to seek medical treatment. An autopsy later revealed the man also had a lethal dose of drugs in his system, but the snake bite contributed to his death.
Forest hikers and even folks enjoying a paddling trip on an Ozarks stream might come across Missouri's largest venomous snake, the timber rattler. Miller said the snakes can grow up to 5 feet long, though most are in the 3- to 4-foot range.
The pattern on their back helps them blend into the forest floor.
"Timber rattlers are documented in every Missouri county, but most people will go their entire lives without seeing one," Miller said. "They do try to blend in with their environment and hope you don't notice them."
Timber rattlers devour large numbers of mice, other rodents, squirrels and some birds. When threatened, the snake often — but not always — will rapidly shake the rattles on its tail, resulting in a buzzing sound. According to the conservation department, timber rattler bites of humans are rare, but their venom is potent and should be treated by medical experts as soon as possible.
The timber rattler's smaller cousin is the pygmy rattler, which is found only in the Ozarks region of Missouri. Miller said the snake typically reaches only 18 inches in length and is the smallest rattler in Missouri.
"They are more prone to be on rocky hillsides in more open areas, like our glades," Miller said.
They have very small rattles on their tails, and Miller said it's rare for anyone to actually hear a pygmy rattlesnake buzzing a warning. Bites are exceedingly rare in Missouri.
"There is no documentation of anyone ever dying from the bite of a pygmy rattlesnake in Missouri," he said.
The snake can be identified by its triangular head and rust or orange-colored spots down its back, in between dark blotches the length of the snake. Pygmy rattlers dine on lizards, snakes, small rodents, frogs and insects.
By far the most common venomous snake Missourians encounter is the copperhead, a close cousin of cottonmouth snakes. Like cottonmouths, copperheads are sometimes seen swimming across streams or ponds where they bodies float high on the water.
Miller said copperheads can be found in nearly any Missouri environment, and it's not unusual to find them in some urban areas that are close to farmland, forests or nearby streams.
"They eat mostly rodents, but copperheads also love to eat cicadas when they just emerge from the ground," Miller said. "Sometimes a property owner might see several copperheads at one time, but they're there to eat the cicadas, which we like to call the 'M&Ms of the insect world.'"
Missouri copperheads can quickly be identified by the "Hershey's Kiss" brown splotches along their sides. Big ones can reach 3 feet in length, though a 2-footer is a good size and more typical of what Missourians will encounter.
More Missourians are bitten by copperheads than any other venomous snake in the state. But according to conservation department records, only three people died as a result of such a bite, in 2012, 1933 and 1965.
Miller said the best way to avoid being bitten by a venomous Missouri snake is to just leave it alone. Many bites occur when someone tries to kill a venomous snake, which puts the person within striking distance of the snake. If you're hiking, be wary of stepping over downed logs, where a snake might be on the other side, and watch where you put your hands if moving along rocky ledges.
If you are bitten, Miller said the best way to respond has changed a lot in recent years.
No cutting, sucking, tourniquets or ice on the wound, he emphasized.
"Keep the wound below the level of your heart," he said. "Keep it cool but don't apply ice to the would. Then get to a hospital. Do not try to bring the snake with you to the hospital. The antivenin we have here works on all four of or venomous species."
Photos: Venomous snakes in Missouri