The Elusive Coral Snake
Easily, one of the reptiles that I am frequently asked about in the southeast, but much less frequently encounter, is the Eastern Coral Snake (Micrurus fulvius). For a snake that is seldom seen in South Carolina, I get almost as many questions about Coral Snakes as I do rattlesnakes, copperheads or cottonmouths.
First of all, as we often do, let’s take a look at that scientific name. The genus name, Micrurus, means “tiny tail”. (Micro = small, tiny or short. Oura = tail.) Snakes in this genus tend to have a rather short tail, which they often use as a distraction when they are threatened. They will lift their short tail and curl it to take attention away from their body and head.
The species name, fulvius, is derived from the Greek term to describe the color fawn, reddish, yellow (or a shade of yellow, orange). The species name was given when a faded and not-well preserved specimen was used to describe the snake. The red on the dead snake had faded to an almost orange color, instead of the vibrant reds we see on live Eastern Coral Snakes.
Next, why don’t we discuss the trick of identifying these snakes? As there are a couple of other snakes that look quite similar and have the same bright colors, combined with the toxicity of their venom, knowing how to correctly identify Eastern Coral Snakes is important. The rhyme, “Red on yellow kills a fellow. Red on black, venom lack” (or, “Red on black, friend of Jack”), is the easiest way to remember the identification of these snakes. While the Scarlet King Snake and Scarlet Snake look quite a bit like the Eastern Coral snake, their red bands and saddles touch black bands or saddles. (See this post’s photos for a better visual on the similarities and differences) Eastern Coral Snakes have banding with red touching yellow bands. This similarity is evidence of the most complex mimicry in nature. Also, Eastern Coral Snakes always have a black nose! If you look at the photos, you'll see the coral snake has a black nose; but, the Scarlet King Snake has a red nose, as does the Scarlet Snake.
Mertensian mimicry is mimicry in which the most harmful species mimics a less harmful species. This goes contrary to Batesian and Müllerian mimicry, in which less harmful, or even harmless, species mimic species that are much more harmful. (Don’t worry, we’ll discuss different types of mimicry in greater detail during a future visit with each other. I promise it’ll come back up again as we talk about insects found on the property.)
As always, if you cannot correctly identify a snake, you should always treat it as though it is venomous! That means give them respect and plenty of space.
The Eastern Coral Snake is the only venomous snake species in South Carolina that is not a pit viper. Instead, it belongs to the Elapidae family, which also includes such snakes as cobras, kraits, mambas and all Australian venomous snakes. Whereas the pit vipers have venoms made up mostly or entirely of hemotoxic proteins, which affect blood and tissue; Elapids have venoms made up mostly of neurotoxic proteins, which affect the nervous system. Their neurotoxic venom is more potent than hemotoxic venom and it takes far less of it to immobilize or dispatch prey when compared to the hemotoxic venom of pit vipers. For Eastern Coral Snakes, prey consists of other snakes, lizards and fellow reptiles.
Eastern Coral Snakes do not have the large, hinged fangs found in pit vipers. They have fixed fangs that are relatively short, often protruding only 1/8th of an inch from their upper labial scales (upper lip). Those short fangs are still very much capable of delivering enough venom to be a lethal dose, which is only about 5 milligrams for a healthy adult. Like other Elapids, Eastern Coral Snakes have proteroglyphous dentition. As we did the last time, let’s break that down to explain this scientific term. In ancient Greek, “proto” was the word for front or forward and “glypho” referred to a carved work. When the two Greek words are combined to describe dentition, it literally means, “having grooved teeth located in the front of the mouth”; which is ideal for describing fixed fangs that are located in the anterior of the mouth.
Despite what anyone may have said, humans are not too large for envenomation by Eastern Coral Snakes. They do not need to gnaw on us for an extended period of time and they do not need to bite between your fingers to cause you serious harm. Those small fangs can deliver their venom anywhere from your legs to your arms. However, Eastern Coral Snakes are the least encountered venomous snake in South Carolina and, like other snakes, they would much rather steer clear of humans. They cannot eat us; thus, they would rather not deal with us. Keeping that in mind, I was grateful to hear Sunshine say she doesn’t indiscriminately kill snakes. She doesn’t accept that whole “The only good snake is a dead snake” mumbo-jumbo. All of our native snakes, both venomous and nonvenomous, are good and they all serve a purpose.
This species should not be found in the lower piedmont area, but it is a great deal more common in Florida and the coastal plain areas of South Carolina. And I wanted to give a comparison to the far more common pit vipers to round out our lesson on the venomous snakes of South Carolina and the southeast
Pit Vipers At Harmony Hill
Though the calendar has now been flipped to the month of March and spring is right around the corner, in South Carolina it has been warming considerably and the signs of that annual rebirth have been popping up everywhere. Days are getting longer, but cooler temperatures are apt to come back to South Carolina perhaps once more before mid-April. Birds have begun their annual migrations north, but the warmth that has been around the last month has been sufficient to get snakes active. Being exothermic, or cold-blooded as I was taught in elementary school, snakes take environmental warmth and warm themselves to activate processes such as locomotion and digestion.
As we discussed in our last visit, there are 38 species of snakes in South Carolina, with only six of those being venomous. Now, there are many that refer to venomous snakes as poisonous, whereas you will hear me only refer to them as being venomous. There is a clear distinction between the two terms, from a biological and scientific point of view. The difference is found in the way a creature delivers toxins, be it actively through a specialized anatomical apparatus or passively through indirect means. Venomous animals, such as some species of snakes, spiders, bees and wasps use fangs and stingers to deliver toxins via injection. Poisonous animals, such as some species of frogs, toads, butterflies and moths are only harmful if eaten or touched. As each of the six species of venomous snakes found here actively delivers toxins through modified teeth known as fangs, they are venomous and not poisonous. Why don’t we start out with a look at some of our venomous snakes?
Five of our venomous snakes belong to a group known as pit vipers. An amazing group, the pit vipers have evolved an incredible ability that has made them the ultimate survivor and predator, especially under the cover of night. As their name implies, members of the Viperidae family, such as Pygmy Rattlesnakes, Canebrake Rattlesnakes, Eastern Diamondback Rattlesnakes, Eastern Cottonmouths and Copperheads, have pits located on their faces between the nostrils and eyes, usually located below either of those facial features. These pits are highly evolved heat sensing organs that serve a number of uses. Being sensitive enough to determine changes in temperature gradients of as little as 1/1000th of a degree, the pits add another dimension of “vision” to the snake and allow it to “see” temperatures more accurately than most heat sensing cameras used by first responders.
Being able to see specific hot and cool changes upon the landscape allows members of the Viperidae family to not only see endothermic prey cloaked in darkness or camouflaged by cryptic colors, but also to find cool places during the heat of the day and warm places on cool nights. While doing snake research years ago at Carolina Sandhills NWR, one of the criteria I would look at when I captured a live snake laying in the road was the surface temperature of the asphalt versus the air temperature at time of capture. Overwhelmingly, we found their ability to detect the warmth of the asphalt roads inside the protected boundaries of the refuge gave them a chance to actively use them as warming surfaces.
Pit vipers also have the most evolved dentition found in the serpent world. They have solenoglyphous dentition. In ancient Greek, “solenas” was the word for tube or pipe and “glypho” referred to a carved work. When the two Greek words are combined to describe dentition, it literally means, “having teeth like tubes”; which perfectly describes fangs designed like hypodermic needles. Viperidae snakes here have independently movable front fangs that are markedly longer than any of their other teeth. In some cases these fangs are about half the length of the snake’s head, which isn’t a problem as they can open their mouths nearly 180 degrees. Viperidae actively inject venom by compressing muscles surrounding specialized venom storage cavities, called lumens. Though their hemotoxic venom isn’t as potent as the neurotoxic venom of the Coral Snake, they are capable of manufacturing and injecting much more in a single bite than a Coral Snake ever could. (More on that beautiful snake when next we gather this week!)
Our smallest pit viper is the Pygmy Rattlesnake (Sistrurus milliarius). You will sometimes see it also spelled “Pigmy”. The scientific name means “Having the nature of a rattle and resembling millet”, referencing the tiny rattle (which is often nearly impossible to hear) and the cryptic coloration that can resemble grains of millet on its back. See the photo I took of a Pygmy 14 years ago to see the “individual grain pattern”. A very old Pygmy Rattlesnake can max out at a length of just shy of 2’, but the average length is between 10”-15”.
During the spring and summer of 2007, I captured and studied 111 Pygmy Rattlesnakes while conducting research. I found a Pygmy Rattlesnake which was 21” long and it was, by far, the largest Pygmy I’ve ever seen. They also come in a wide variety of colors; but, the pattern tends to stay the same, regardless of the overall color. (Side note, they are also pretty common in Florida. You may have seen a few down there.)
Pygmy Rattlesnakes are considered a much older species than the other rattlesnakes in South Carolina (or North America, for that fact). Their venom is weaker than their pit viper relatives and their head scales more closely resemble some nonvenomous snakes. And, with such a small rattle, the general consensus among biologists is that Pygmy Rattlesnakes predate the other pit vipers by several thousand years.
Our next largest rattlesnake is the Canebrake, or Timber, Rattlesnake. They are the same species (Crotalus horridus); but, are referred to as Canebrake Rattlesnakes in most of the Sandhill and Coastal Plain areas of South Carolina. When you get into the Piedmont and Mountain areas of the state, the snake is called Timber Rattlesnake. Their scientific name means “Horrible castanet”, which is both funny and sad. They do have a type of castanet on the end of their tail, but I would argue they aren’t horrible at all!
They are a beautiful tan or beige color, with dark chevrons down the length of their body. There is also a rust-colored line that runs along the spine of the snake. If you’ve seen them in the forest or in a field, you know how quickly they can disappear into the leaf litter or vegetation. There was a 3’ Canebrake Rattlesnake that would often hang out near one of the mist nets at a bird banding station I operated and, even with me knowing to be vigilant and have my awareness high, that snake would often be very near without me seeing it until I was close to it. (Thankfully, it was a very well-behaved snake, and it knew I wasn’t a threat.)
Our last, and largest, rattlesnake is the Eastern Diamondback Rattlesnake (Crotalus adamanteus). With a common name like that and a scientific name meaning “castanet with diamonds)”, it goes without saying the large diamonds on the snake are the identifying feature. Unlike their western counterpart, the Eastern Diamondback does not have a black-and-white striped tail before the rattles. (This gives the Western Diamondback Rattlesnake the colloquial name “coon tail rattler” in much of its range)
Eastern Diamondback Rattlesnakes are big. There is no other way to put it. It is not uncommon for a mature Eastern Diamondback to reach 6’ in length. The last time I checked, the largest measured was 8’ long. It is also not out of the question for these snakes to weigh in at 8-10 pounds. They are big snakes! And, like the Pygmy Rattlesnake, they are quite common in the palmetto and pine forests of Florida.
The genus, Agkistrodon, contains both the Copperhead and Eastern Cottonmouth. The genus name translates to “tooth like a fishhook” and implies the large fangs are, in fact, curved in shape. Let’s look at our last two pit vipers…
The Copperhead (Agkistrodon contortrix) is, in my estimation, the most common venomous snake found in the lower piedmont area. They are most often found in drier, more upland areas from their cousin, the Cottonmouth. In fact, their family relation and that tendency has led to their colloquial name of “Upland Cottonmouth”.
True to their common name, they are a beautiful copper color overall, with darker hourglasses wrapping around their width. One quick aside, there are “northern” and “southern” subpopulations and the way to tell them apart is that “northern” Copperheads have spots between their hourglasses, while the “southern” Copperhead is cleanly colored in just copper and hourglasses. Where their ranges overlap and they interbreed, there will be intermediates with a nominal number of spots accompanying their hourglasses.
Copperheads are able to make their smelly musk into an aerosol and can spray it around themselves and towards a threat. I learned this lesson the hard way while doing the snake research at Carolina Sandhills NWR in 2007. I had a new Jeep Grand Cherokee and stopped in the road to catch a Copperhead in the middle of Wildlife Drive, only to have it spray a fine and invisible aerosol of musk at me. I was not at all affected, but the musk got into the air conditioning filter and vent of my Jeep and there were a couple years afterwards where you could smell hints of that musk after turning on the air conditioner for the first time in the spring. Lesson learned!
Like its cousin, the Cottonmouth, young Copperheads are born with lime green tails that they use as bait to lure in prey. They will hide under leaf litter or vegetation and wiggle their lime green tails out in the open, attracting everything from frogs and toads to worms that they hope to dine upon
Finally, in our long lesson on the pit vipers of SC is the Eastern Cottonmouth, or Water Moccasin. Their scientific name of (Agkistrodon piscivorus) and means “fish devourer with fishhook tooth”. They are, without any competition, our most aquatic venomous snake in the Harmony Hill area. They love to be in and around slow-moving water, like creeks and swamps. While they can be found around ponds, they don’t tend to like large water and aren’t found around lakes that often. They can also be found in dry areas, but that is when they are moving from one aquatic area to another.
Harmony Hill is on the very northern edge of the range of this species. They will eat anything that will fit in their mouths and I do mean ANYTHING that will fit in their mouths. While they make a very good living eating fish, they will eat very young turtles, alligators, mammals, birds and other snakes. While doing the snake research, I captured a couple of Eastern Cottonmouths with large, circular scars on their sides (about the size of a dime). I was confused as to what may have caused the scars, particularly since they were somewhat the same size and found on separate snakes. I posed the question to a herpetologist friend who said it was likely the result of catfish barbs that were poked through the snake, from the inside… a last gasp of survival from a catfish being devoured by the snake.
This species has the reputation of being aggressive and, to hear my grandmother tell it, they would all but follow you home and set your house on fire. She told me tale after tale of Eastern Cottonmouths chasing people to bite them. Turns out, she wasn’t exactly right. Cottonmouths will stand their ground and don’t retreat like other snakes. They will gape their mouths open, showing that cottony white mouth and even reinforce it with a hiss. However, they don’t chase, and they don’t readily bite. The vast majority of bites are in response to being harassed or when people are trying to kill them.
I’d like to point out that situation appears to be a common thread among many snake bites from the species we’ve learned about today. They don’t actively seek to bite humans and most snake bites are the result of the snake defending itself.
Snakes: Evolutionary Marvels!
“I just don’t like them.”
“They look creepy.”
“I hate them.”
“I’m scared to death of them.”
“They are the most evil creatures on Earth.”
These are actual responses I’ve been given concerning one of my favorite animals. Whether those attending the many nature walks I lead or simply individuals contacting me to identify what they’ve encountered, when I say how much I like and appreciate snakes, I invariably get some version of these answers from the majority of folks. There is no single group of animals that evokes such a reaction among people in this region. I had someone tell me, as a point of fact, it was due to snakes being cursed after the infamous Garden of Eden incident. But, you know me well enough to know I’m going to look a little deeper into the culture and ecology of it.
This subject came up with fellow anthropologists at a conference once and neither of us thought that a tale from the bible explained fully the image of snakes in human culture or the root of any negative image of snakes by humans. Many cultures around the world and throughout human history have, in fact, seen snakes as less than desirable. This is far from a rule of thumb; however, as there are many cultures that view snakes in very positive ways.
Greek mythology tells of Asclepius, the god of healing and medicine. Asclepius, the son of the god, Apollo, was raised by a centaur and taught the art of healing. While a phenomenal student, it wasn’t until a snake whispered the deepest secrets of medicine in his ear that Asclepius became legendary among both mortals and gods alike for his ability to diagnose and to heal. According to the Greek tales, snakes were revered for being keepers of the knowledge of medicine, wisdom, and even resurrection. They were sacred creatures in Greek culture and far from the bane of all creation they are portrayed as in much of American culture. Even in modern times, we see the Rod of Asclepius used as a symbol of healing. The logo of the American Medical Association is that of a staff entwined by a snake, tracing the origins of medicine back to the myth of Asclepius. This particular topic will come back up when we discuss milkweeds in the coming installments, as we tie species together (even those you may not think are related).
Also, as another aside, there are some medical establishments and groups using a logo with a staff with two snakes display a caduceus, belonging to Mercury (or Hermes, depending on which tale you read). The mix up with the staffs may go back to the practice of alchemy. The staff with two snakes, or caduceus, appears to have been adopted by US military medical corps in the early years of the 20th Century; but the AMA logo is the staff of Asclepius. This also seems to be something that only occurs in America, as the rest of the world pretty uniformly uses the staff of Asclepius for medical practices, not the caduceus of Mercury (or Hermes).
Have snakes always been seen as vile and putrid in America? The answer to that question is, quite simply, “No”. Several Native American cultures have stories of snakes being administers of justice, immortality, and transformation. Various First Nations’ tales depict the Lightning Snake, He’-e-tlik, as an enforcer of Nature’s Moral Code. Should anyone forsake the rules of proper hunting or fishing, or should they needlessly harm or kill any animal, He’-e-tlik would disfigure them. He’-e-tlik was so powerful that he was the constant companion of the Thunderbird, Tootooch. Tootooch, the most powerful creature to have ever lived, hunted Orcas by unleashing his friend, the Lightning Snake, upon them. He’-e-tlik was indeed well respected by those residing in northwestern North American.
In the American southwest, The Pima depict the rattlesnake as the most gentle and meek animal on earth, calling him Soft Child. One version of the Pima tale says all creatures were given the chance to decide what gifts they would be given by the Sky Spirit to protect themselves. While some chose claws, teeth and cunning, the rattlesnake only asked for a way to let others know he was there, since he was low and could be easily stepped upon. The Sky Spirit, in granting his wish, gave the rattlesnake its well-known rattle as a warning to the other animals. Unfortunately, the rattlesnake was so meek that some of the other animals mocked him and poked fun at him nonstop. One animal in particular, the rabbit, would always seek out the rattlesnake to tease him.
Seeing the way the rattlesnake was treated, the Sky Spirit came down one evening and visited with him. In an effort to level the playing field, the Sky Spirit gave the rattlesnake fangs tipped with lightning bolts, knowing the snake would only use them as a last resort. The next day, the rabbit came poking and kicking the rattlesnake until he could no longer take it. No matter how much the snake rattled and warned the rabbit, the teasing did not cease. In less time than it takes to blink an eye, the rattlesnake struck the rabbit with his lightning fangs and killed him. To this day, the rattlesnake is so gentle and meek that it will always rattle to warn that it is there, in the hopes it doesn't have to use the lightning bolt fangs it has.
Clearly, not all cultures painted snakes in a negative light; with many having great respect for them. What about how we respond of snakes? Where does that come from? For that answer, we’re going to have to go back much farther than the 10,000 years that saw early North American settlers and the rise of ancient Greece. For that answer, we’re going to have to go back about 80 million years ago, before primates diverged into the suborders Haplorrhini and Strepsirrhini.
Our ancestors were tree-dwellers and their biggest predator predated them by about 40 million years. Snakes have made a very good living hanging out in trees and eating whatever they can get in their mouths. Stealthy hunters, snakes are extremely adept at sneaking up to primates and preying upon them. Even today, snakes continue to hunt and eat primates. Our ancestors had to develop an acute awareness and ability to locate danger, such as a reptilian predator.
Recent studies have shown that primates have a much more acutely developed recognition of snakes. The pulvinar portion of the primate brain, which is responsible for receiving and processing signals from the eyes, has 91 extra, highly developed neurons when compared to other mammal pulvinar. These extra neurons are responsible for directing our attention, such as recognizing and being alerted to the presence of a snake. It allows us to recognize and spot the shape of a snake in our surroundings. Individuals with damaged pulvinar portions of their brains have increased difficulty focusing and become distracted with little or no reason. On a side note, I really could’ve used that excuse as a child when I couldn’t sit still in class or didn’t pay attention at home. “But I have a damaged pulvinar!”
When studied, primates have shown instantaneous recognition of snakes. Further reinforcing this instinctual response is linked to specific recognition is that it’s even seen in primates that were raised in labs. These primates had never seen a live snake before the experiment. With further research, it was proven the reaction to snakes is not learned, but is hardwired from our primate ancestors. It is a perceptual bias; that is, we recognize the shape and presence of snakes faster than other objects in our environment. Even those of us without an irrational fear of snakes have similar pulvinar responses.
You’ll notice this is the first mention I’ve made of fear. Living in the lower piedmont, people have scant reason to fear snakes. There are 38 species of snakes in SC, with only 6 of those being venomous. The 6 venomous snakes found in SC are: coral snake, copperhead, eastern cottonmouth, pygmy rattlesnake, canebrake (timber) rattlesnake, and the eastern diamondback rattlesnake. Of those 6, only 3 are fatal to healthy adults: the coral snake, canebrake rattlesnake and the eastern diamondback rattlesnake. Copperhead and eastern cottonmouth bites may be fatal to very young, old, or those with compromised immune systems. The last time I checked, there are no recorded human fatalities due to the bite of a pygmy rattlesnake. All snakebites that could occur in South Carolina are treatable, with quick and proper medical attention.
Since 2010, there have been 25 fatalities linked to venomous snakebites in the United States. Two of those fatalities were caused by nonnative exotic pets, a Monocled Cobra and a Black Mamba. Seven others of were due to improper and careless handling; one by someone attempting to determine the sex of the snake and four were during snake handling religious ceremonies. Just one fatality has been reported in South Carolina in over 90 years and that was a good friend and colleague, Wayne Grooms. Wayne was hiking at the Cuddho Unit of Santee NWR and, while walking along an area of riprap along the Lake Marion Shore, he was bitten by a Canebrake (Timber) Rattlesnake. Wayne was 71; but had a couple of health issues. He passed away within 15 minutes of being bitten, which is EXTREMELY FAST AND HIGHLY UNUSUAL for a snakebite from a Canebrake (Timber) Rattlesnake.
As a comparison, according to NOAA there was an average of 26 deaths each year related to lightning strikes in the United States from 2010 - 2019. That’s more people each year from lightning strikes than in the last 11 years from snakebites. So, you are far more likely to die from a lightning strike than from a snakebite!
Yet, with the likelihood of a fatal snakebite being so low, people still fear and hate snakes. Perhaps it's the way snakes move. Slithering around on their bellies, their locomotion is alien to us. We identify with animals that walk. Though they once had legs, vestigial pelvic spurs prominent in large snakes show the remnants of a pelvis and femur bones, snakes left walking behind in favor of burrowing, utilizing smaller spaces, and even swimming more efficiently. Admittedly, watching a snake as it crawls along the ground or swimming in the water gives pause. But, that is no justification for the level of hatred leveled at snakes.
Six states still host “rattlesnake roundups”. Atrocities and circuses woefully disguised as educational events to teach, these roundups are nothing more than public butchering of rattlesnakes on a wholesale level. Last year, at a roundup in Sweetwater, Texas, an appalling 3,900 pounds of rattlesnakes were slaughtered in the name of tourism and festivities. For a period of weeks or even months, rattlesnakes are flushed out by spraying noxious gasoline in their burrows and are gathered in drums and barrels. When the roundup comes around, the snakes are paraded around, killed, and skinned for those in attendance. Claiming they are trying to reduce the possibilities for snakebites, people with little or no education in natural history search far and wide for animals that pose little threat to them. Most carry guns for protection; lest the snakes they are harassing and capturing attempt to protect themselves. Now, if you’re looking for the most evil creature on earth, may I nominate zealous, uneducated people with guns out hunting for rattlesnakes?
This was, as last week with owls, and introduction to the myth and even the physiology of snakes, as well as how humans and primates process being around snakes. In our next visit, we’ll take a closer look at a few of the 38 snake species found in South Carolina. With any luck, by the time we’re done, you will all see that snakes are not vicious beasts out to kill you. Instead, they are incredibly interesting, even beautiful, animals that aren’t deserving of fear and demonization. They are, however, deserving of respect and conservation.