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Reptiles and Amphibians:
The Field of Herpetology
A reinforcement to me that ignorance about amphibians and reptiles in general and about snakes in particular prevails at all levels of education came at midnight in a small South Carolina hospital in July 1971. The scenario began four hours earlier with a phone call to my house. Dave, an undergraduate research participant, was calling from the Savannah River Ecology Laboratory to say that Rita, another student, had been bitten on the foot by a canebrake rattlesnake.
Full of the enthusiasm we instill in students for working with animals and meeting them on their own terms whenever possible, Dave, Rita, and a third student, Jim, had set out to do some road collecting earlier that evening. Patrolling the blacktop roads of the SRP for three hours, they had picked up two scarlet snakes and a corn snake. It wasn't raining so the only amphibians on the roads were toads who despise cold weather but seem to ignore the lack of moisture. The students had started early, at twilight, for that was the best time to find the normally crepuscular canebrake rattlesnake.
Everyone looks for the canebrake when they road collect in South Carolina. The canebrake is a prize. A trophy. You may come up with a justification for collecting specimens of one type or another, but every reptile-oriented herpetologist awaits the canebrake. It is a thrill seeker's species. And the three students found their thrill at 10:30 P.M.
Clipping along through the pine plantations, they had seen nothingfor thirty minutes, save a fast-moving gray fox. Then they entered the valley of Upper Three Runs Creek. From the air the creek and its corridor of bottomland hardwoods appear to weave a sinuous path from the farmlands to the northeast across twenty miles of protected lands on the SRP. The hardwood corridor is a mile wide at some places and grades from annually flooded swamp forest habitat up into the dry-land oaks and hickories. Finally, at the top of the ridges, the smaller descendants of giant loblolly and longleaf pines now live.
The canebrake that got Rita could have crawled out from any of these places. As far as I can tell, canebrake rattlers are not as particular as most snakes about where they live. They are discriminating about when, however. A canebrake is seldom seen in the springtime in South Carolina before late April, although almost every other snake species will have already come and gone in number. Also, in the summer, canebrakes are nocturnal. They like to be out at night, but they do not care where they are, as long as mice, rats, and rabbits don't mind being there, too.
All three students saw the snake at the same time: a thin white line in the right lane, exactly perpendicular to the highway, with the front end elevated a few inches above the blacktop. Dave wheeled the gray government pickup to the left and braked as he went around. Knowing how things work when a bunch of herpetologists see a snake on the road, I'm sure there was a scramble for the flashlights and a snake stick. Everyone was probably being loud and imperative.
You have to hurry for most snakes, because they keep moving. And, at night, once they disappear into the grass on the shoulder of the road you most likely have lost them. But canebrakes are different. Canebrakes usually freeze when your headlights first shine on them, and they patiently lie and wait for you to get out of your truck. Not knowing this fact, however, Rita was in a big hurry.
As Dave backed up the truck, Rita opened the door, ready to jump. Running over a specimen when you're backing up is an embarrassment of the first order to a herpetologist. So, Dave stopped in the left lane before he had gone too far, he thought. Rita jumped out onto the highway.
Students enjoy going barefooted in the summer, and normally there is no problem as long as they don't mind the briers. But I now advise my students to be careful if they collect snakes and do not have on shoesbecause that night Rita landed right in the middle of the rattlesnake's back. And who can blame the snake for what happened? The canebrake bit Rita on her big toe. I met the three students at the emergency entrance of the hospital, having already informed the night duty personnel that a snakebite victim was on the way.
The intern on duty, Dr. Plunt (the only fictitious name used in this book, for reasons that will become obvious), and I got our acquaintanceship off to a poor start when he reproachfully asked the students if they had brought the snake with them for identification. That was his mistake, founded on ignorance. My error was in pointing out his mistake to him. I told him that as long as it was not a coral snake, something anybody could identify, any poisonous snake in the South was a pit viper. The treatment for all of them is the same. They even use the same antivenin as a poison neutralizer.
Not surprisingly, he didn't like my intervention. After all, he was the doctor, as he said. I stated that I was too and that with a Ph.D. in zoology and a specialty in herpetology I had seen more snakebites than he had. It turned out to be true. This case was his first snakebite and my second.
As Rita stood by patiently, Dr. Plunt ended our exchange by storming through the door that led into the back of the emergency room. Over his shoulder he shouted some orders to the two nurses. One began to get out some surgical instruments as the other bathed Rita's foot.
The rest of us looked on to see how bad the swelling was. To be sure, the front part of her foot was red and plump. A tiny red pinhole could be seen in the center of her big toe. A fang mark. I looked carefully and concluded she had been hit by only one fang. In my estimation the probability of serious consequences immediately dropped to one-half. Also, the rattler had been a small one, further diminishing the chances of any real danger to Rita. In fact, if her disposition were any measure of the seriousness, one might think that nothing had happened. Rita was in a most agreeable mood and was bearing up exceptionally well for someone suffering from the pain of a poisonous snakebite. Even a minor bite like this one can be painful.
I began to relax and prepared myself to apologize to Dr. Plunt. I intended to explain to him that I had been tense because I was unaware that the bite was not a serious one. Yes, despite his officious nature, I truly was ready to apologize without pointing out his ignorance a second timewhen he roared back into the emergency room brandishing a 20-ml syringe full of antivenin. All thought of apology vanished from my mind.
My level of anger and annoyance rose even higher when Dr. Plunt ignored me and did not answer my question about what he intended to do with the syringe and needle. Upon further inquiry, he finally answered that he was going to proceed with antivenin injections. When I began to admonish him for planning to administer antivenin without even examining the bite carefully, he lashed out at me by pointing out that he was a "real" doctor. I countered that I was the "real" doctor with my Ph. D. because the word doctor meant teacher and I had not seen him teach anything yet that was correct. I then went on to expound on the dangers of the horse serum-based antivenin and the potential for anaphylactic shock and other dread things about which I knew nothing.
When Dr. Plunt slammed the still-full syringe down on the counter and stormed into the back room again, I had the feeling of intellectual triumph. If he really knew what he was doing he would have -proceeded with the injection. Obviously he was not confident about his stand. Within moments, though, an uneasiness came over me. Had I been overconfident? I only knew what I had read. Perhaps the bite was more serious than it seemed. A basic antibiotic and a painkiller should be all that is needed for many North American snakebites. Was this remedy really what Rita required? With an audience of three students and two nurses looking on, I certainly hoped so.
At that point I decided to meet the arrogance of ignorance face to face. Seeing Rita still in good spirits (over an hour had passed since the bite) and perceiving the uncertainty of the intern, I boldly declared that the bite was not even serious enough for Rita to stay in the hospital overnight. I went to tell Dr. Plunt.
As I pushed open the swinging door, a startled Dr. Plunt quickly stuffed a book into the drawer of the desk where he stood reading. He came toward me, declaring that he must begin cutting and suction. Again I was aghast, as this treatment was considered totally unnecessary under the conditions of minor swelling. He brushed past me, and I started to follow, to take my stand against overtreatment by the medical profession. But, when he went out the door, I did what you might have done. I went to the desk and opened the drawer. His medical source might be revealing.
And wasn't it! The Boy Scouts of America Handbook! The same edition that I had used two decades earlier while trying to get enough merit badges to keep my status in the neighborhood. The edition with the cover of a scout building a fire. Dr. Plunt was sneaking his information about snakebite treatment from an out-of-date scout handbook that only considered first aid in the field. I rushed back into the emergency room. It was not difficult to detect the apprehension that came over the faces of the other five as Dr. Plunt and I prepared for another showdown.
The handbook evidence was too embarrassing to mention with Dr. Plunt there, but I did declare what should be done. Antibiotics. A painkiller. A night's rest in the hospital under observation. He called my bluff by saying he would not prescribe anything while I was there. Furthermore, he declared that Rita was officially admitted into the hospital. The only way be would allow me to remain in her presence would be for me to sign a statement that I took full responsibility for her well-being and that she would then have to leave. In my opinion, this tactic was a low blow. But it didn't matter anymore. I took the bet and we all left, Rita hobbling between Dave and Jim.
Fortunately, in Rita's case I was holding the high hand. She took some aspirin that night and by the next afternoon the swelling had subsided. No secondary infection developed. Anything the doctor might have done certainly would have been overtreatment and potentially costly in more ways than one.
The whole scene scares me when I think back. Both of us, supposedly trained professionals, "doctors," were operating in a very dim light. My only saving grace was that I recognized his ignorance about the situation even though I was not sure about my own knowledge. Perhaps I was lucky, or Rita was, that my ignorance did not come into play in a manner that made a difference to her welfare.
Only after many years have I come to realize that certain knowledge must come from experience. Such is true of snakebite treatment, because each snake and each victim is a composite of numerous variables that affect the outcome. Because snakebite is a rare occurrence to the medical profession, most physicians in the United States have never seen a snakebite victim. Hence they do not have experience on which to rely. Nor do we, the research ecologists and herpetologists, have experience that would be gained from extensive research on snakebite. Support for a rare medical problem such as snakebite cannot possibly command the research dollars that more visible problems such as cancer, heart disease, or diabetes do. Hence, in comparison, a minimal amount of medical research is done.
Snakebite is something that very few people, including professionals, know much about. But the entire realm of herpetology is in the same situation of wholesale ignorance not only in regard to most lay people but to the overwhelming majority of professional biologists, too. Of the five major classes of vertebrates, people know more about fishes, birds, and mammals than they do about reptiles and amphibians. This situation is evidenced in popular wildlife literature and in general discussions with people from all regions. Furthermore, the information that people provide about herpetofauna is misknowledge based on misinformation of various sorts or on such a limited supply of knowledge that misconception and superstition easily can be spawned. In my opinion, there are three primary reasons for the low emphasis placed on teaching and learning about reptiles and amphibians as compared to other vertebrates.
1. Few reptiles and amphibians have any commercial value as food or clothing, nor have they been essential to the welfare of a populace in a region; therefore, there has been little economic incentive to understand the life history or general biology of most species.
2. Because of the low numbers of species and the highly secretive nature of most forms of reptiles and amphibians, they are encountered far less frequently than the more numerous and obvious types of animals in this country.
3. The potential venomous nature of certain species of snakes and lizards and the man-eating tendencies of certain crocodilians have led to a psychological avoidance of these groups of animals. Uncharitable attitudes have extended to many nondangerous species, including most lizards, most snakes, and even a few completely harmless salamanders. The result is ignorance caused by an inclination not to be associated with these particular types of animals.
Each of these three reasons warrants discussion.
1. Commercial valueOnly a few of the 450 species of reptiles and amphibians that occur in the United States have any significant commercial value. Although many species are edible, their small size or their success at being inconspicuous makes them unattractive from a commercial standpoint. A few species of reptiles and amphibians in this country have been exploited, however. In the nineteenth and early twentieth centuries, the diamondback terrapin, a coastal species of turtle ranging from Chesapeake Bay to the Gulf of Mexico, was commercially harvested and sold as a delicacy for soup or stew. At one time the Bureau of Commercial Fisheries even established a turtle-rearing program to see if this species could be raised successfully in captivity to provide for what appeared to be a rapidly flourishing market. As might be expected, the slow growth rate of individual turtles and long term (at least four years) for the females to reach maturity reduced the pursuit of this endeavor. Concomitantly the overexploitation in the coastal areas gradually reduced the turtle population to a point that a sufficient yield was no longer possible, and the use of diamondback terrapins for restaurant fare waned.
Likewise, certain of the marine turtles, such as the green turtle, occurred in southern coastal waters of the United States and once were heavily utilized as the base for turtle soup. Declining populations and the placement of most species onto legally endangered species lists put an end to this effort. Many turtles, of course, are eaten regionally, such as the chicken turtle in many parts of the South, the gopher tortoise in southern Georgia and Florida, and the various species of slider turtles in the eastern United States. The snapping turtle seems to be eaten throughout most of the United States. At best, however, turtle as a source of meat is a highly localized phenomenon.
Perhaps the most popular amphibian food source is frog legs. The legs of any frog would be satisfactory to eat, but in this country the only common species obtaining a size suitable for making a meal is the bullfrog. Attempts have been made to raise bullfrogs commercially in some parts of the South and in some instances thousands of pairs of legs per year have been sold for food.
Rattlesnake meat is still sold as a delicacy in parts of the South. Much of the supply comes as a result of the famed rattlesnake roundups in Georgia, Oklahoma, and other areas. Many species of snakes are edible, but only rattlesnakes attain a size large enough to obtain a sufficient supply of meat to make the effort of catching the animal and processing it worthwhile.
No lizards in the United States are considered a food source, although many species are edible. However, in Central and South America the large iguanas are a common food item of the natives of the region and are served in a variety of ways. The American alligator is a popular food with people who have eaten alligator tail. The meat is white, has the consistency of pork, and, if properly prepared, can be served as steaks. Legal limitations were imposed on this food item in 1973, by official placement of the alligator on the endangered species list throughout the country and by its remaining in endangered or threatened status in most regions.
Most herpetologists have had at least limited experience with eating their study organisms. Ernie Liner of New Orleans has published a book on the subject entitled A Herpetological Cookbook: How to Cook Amphibians and Reptiles. At SREL we have had our own experiences with some of the local fare at what we call the "Herp Dinners." The objective is to try to eat examples of all of the major groups of regional reptiles and amphibians with which we work. The animals used for food are taken primarily from specimens found recently killed on local highways or from specimens that were sacrificed in the laboratory as part of experiments.
The first Herp Dinner, in 1977, was an outstanding success. Besides the local graduate students, such as Bob Parmenter and Joe Schubauer who worked with turtles, and Pat Murphy who studied alligators, we had visiting herpetologists from Michigan (Don Tinkle and Justin Congdon), Texas (Gary Ferguson), and Chicago (Ken Derickson). The final spread was magnificent and included sautéed alligator tail (legally obtained and frozen in 1971 after a large male was killed by a logging truck); legs of bullfrogs, leopard frogs, and green frogs; snapping turtle salad (excellent on crackers); slider turtle stew; crispy fried mole salamanders; baked canebrake rattlesnake (a 4 1/2-foot specimen coiled around tomatoes and green peppers); and deep-fried strips of cottonmouth moccasin. Although all of the representatives were unusual compared to a typical American meal, two of the items stood out in uniqueness and were declared to be the best and worst of the evening.
The "best" was a consequence of our having collected thirty-six male banded water snakes at a place called Flamingo Bay the night before. Even with eight of us walking around in the water, a total of forty-seven snakes (the thirty-six males plus nine females and two cottonmouth moccasins) was a lot to catch in one night. And fortunately they filled our need for a sample of water snakes to dissect to determine reproductive and lipid cycles in the species. During the Herp Dinner the following night we served part of the sample as hors d'oeuvres that were as well received as Oysters Bienville or Crab Louis. Everyone loved them and complained bitterly when the seventy-two "swamp oysters" as we called them were all gone. Only later did Bob Parmenter and I reveal that we had served perhaps the largest appetizer tray of water snake testes ever eaten in the United States. Let me repeat, though, they were excellent!
The "worst" item of the night had no close contestant. Gary Ferguson disappeared from the room "ill" after the first bite, and none of us was able to swallow any. The food was fried blue-tailed skink, one of the three species of local lizards with a brilliant blue tail. Although none of us has published on the subject in the scientific literature, we did conclude that to less naive predators than ourselves an attractive blue tail probably serves as a warning that a skink does not taste good.
We have continued the Herp Dinners at SREL, experiencing such new entrées as Laurie Vitt's soft-shell turtle casserole and Trip Lamb's snapper gumbo. Despite the appeal of herps as unusual delicacies, their exploitation for such purpose on a grand scale is never likely to be profitable.
Besides their use as food, reptiles and amphibians also have been commercially exploited for other purposes. Certain salamanders, for example, are sold as fish bait in some areas. The most apparent impact on a North American reptile species was the exploitation of the American alligator for hides to make shoes, belts, and purses, resulting in the elimination of the species in many parts of its range during the mid-1900s. In addition many species of reptiles and amphibians have been, and still are, sold as pets, although this practice is based mostly on incidental captures of various species. One market that is no longer in effect is the sale of baby turtles, primarily painted turtles and certain species of slider and map turtles. The demise of this market was partially a consequence of their being implicated as carriers of Salmonella, a form of bacteria that causes a severe intestinal ailment. Nonetheless, despite these few examples of commercial uses of herpetofauna, the impact on the commercial market has been trivial compared to that of mammals, birds, and fishes, although the impact on the animals themselves has in many instances been severe.
2. Secretive natureIn a scientific sense, reptiles and amphibians are no more closely related than reptiles and birds, yet their study is combined into a single field, herpetology. The word comes from the Greek word herpeton, meaning "creeping thing," and sums up one of the qualities that link the Class Reptilia and Class Amphibia. Most species indeed can be ascribed as creepers, which combined with another trait, smallness, leads to a general characteristic of being clandestine. This overall feature of secretiveness is a major reason why reptiles and amphibians are artificially included together in a single field, whereas fishes, birds, and mammals are studied separately. That is, reptiles and amphibians are superficially similar in their selection of habitats and are likely to be found in the same kinds of places. In many areas, when you turn over a log in the woods you are as likely to find a reptile as an amphibian. Because they are found together, they are studied together.
The actual numbers of species of any major group of animals can never be known for sure but accurate estimates have been made for the vertebrates. Amphibians are at one end of the species scale, with only about 3,000 representatives worldwide, whereas fishes with over 17,000 species are at the other. The world contains about twice as many kinds of reptiles (6,000 species) as amphibians, more than the mammals (about 3,500 species) but fewer than the birds (about 8,600 species)
Relative to the other vertebrates, reptiles and particularly amphibians are inconspicuous far beyond what might be expected on the basis of the numbers of species or individuals that are present in an area. Even though the mountains of Tennessee and North Carolina have the greatest concentrations of salamanders in the world, many southerners have never even seen a salamander. The explanation is simple. Most salamanders are small and inconspicuous to begin with and the habit of most is to live underground or under leaf litter or other forest debris for the majority of their lives. When they do venture forth, it is usually on rainy nights, a time when nonherpetologists are least likely to be out.
The fact that few people like to get outside their living rooms on a rainy night, particularly when it involves going into a swamp or woody area, is one reason that people are not more aware of how many frogs occupy most parts of the country. In short, the behavioral habits of most humans do not overlap at all with the behavioral activities of most frogs. Who is likely to hear a breeding chorus of two hundred spring peepers on a cold rainy night in February along the Atlantic seaboard or the ceaseless quacking of a thousand green tree frogs during a summer thunderstorm on a barrier island? When daylight comes and the humans emerge, the frogs are all gone, buried deep beneath the vegetation, mud, or other hiding places until the right nighttime conditions occur for them to emerge again. Most frogs are this way, being active mostly at night and making a racket that calls attention to themselves primarily when it is raining. Otherwise they are quiet and inconspicuous during the times when humans are active.
Turtles are perhaps the most conspicuous of the reptiles or amphibians because of the propensity of a few species to bask in the sun where people can see them. Most turtles are very shy and quick to retreat into the water off a log if they are disturbed. But some species congregate in large numbers in certain areas if they go unmolested. Also, almost everyone has seen a box turtle in those parts of the United States where they occur, wandering through the woods or alongside roads or sometimes making the fatal mistake of trying to cross one. So turtles really do not qualify for the same level of inconspicuousness that most of the other reptiles and amphibians do.
Snakes have their own style of secretiveness, much of which comes from staying out of view throughout most of their lives. In some of the snake-dense areas of the country, such as the Southeast, people may spend their whole lives living in an area where thirty to forty kinds of snakes occur and yet may never see more than half a dozen different kinds in their life. Part of the snakes' secretiveness comes from actually hiding underground or concealing themselves in various ways. But many snakes go unseen because most people are inexperienced in spotting them, even when they are close at hand, because of effective patterns of color and camouflage. Lizards likewise are frequently in view to people but go unseen because of effective camouflage.
So, despite the obviousness of a few reptiles, such as basking turtles and large snakes, most reptiles and amphibians cannot compare with the ever-present birds and fishes for conspicuousness. Mammals indeed are more secretive in nature than fishes or birds but, if one considers the numbers of squirrels, rabbits, mice, and occasional opossums and deer that we see, the herpetofauna are definitely in last place in terms of being seen by people.
3. Psychological avoidanceMost people tend to avoid anything that is threatening, distasteful, or unpleasant in some way. Avoidance of a subject maintains ignorance about it and is perhaps one reason why reptiles and amphibians are so poorly understood. It is no myth that certain snakes and at least two species of crocodiles have been responsible for numerous human deaths. This fact scares people: to think that a lower life form can callously kill or even eat a human. Consequently, the most prudent approach has been considered to be one of keeping a safe distance from such creatures that show themselves to be cold-blooded in more ways than one. Such an attitude, based on fear, is unlikely to promote knowledge of the animals in question.
Reptiles intentionally cause human deaths in three different ways. The most common and well-known means whereby certain snakes and two southwestern lizards can kill people is by means of injection of venom. All of the warm continents have poisonous snakes, capable of giving a lethal bite. This fact probably has resulted in a mindset in many cultures that all snakes can be dangerousfor rather than attempt to learn which ones are poisonous and which ones are not, it usually has been easier to avoid all snakes and to teach others to do the same. This notion has no doubt been the safest-approach for individual humans and for the culture but not for the harmless species of snakes.
Other examples of reptiles that have killed people are the Nile crocodile of Africa and the saltwater crocodile of the Australian-Malaysian region of the world. Both of these species unquestionably and unremorsefully will devour a human being if the circumstances are suitable. The mentality of a saltwater crocodile, which does, incidentally, come far inland into fresh water, appears to be no different from that of a great white shark when it feeds. Therefore, a human who is small enough for the crocodile to handle is fair game. Unfortunately, a saltwater crocodile may reach a length of more than twenty feet and can have a jaw length of more than two feet. Needless to say, no human is a match to such an animal. These Old World crocodiles have given a lot of bad press to their New World relatives, none of which is particularly dangerous unless provoked or cornered. Americans have been trying for decades to indict the American alligator as a killer. But American alligators are like house pets compared to the Old World maneaters.
The final example of intentional killing by a reptile is the case of the large constrictors. A few cases are on record of South American anacondas and some of the Old World pythons (snakes reaching lengths of more than twenty-five feet) having attacked, killed by constriction, and then eaten humans, usually children. No poisonous snake ever has been known to eat a person. Despite the few tragic instances of large constrictors' eating or attempting to eat humans, among the reptiles only the two species of Old World crocodiles can be accused of making humans a regular part of their diet through the ages.
Amphibians, of course, do not kill people. Hellbenders, the large ugly salamanders living in mountain streams of the eastern United States, sometimes are thought to be poisonous but are harmless. The secretions from the enlarged poison glands located behind the head of some toads are deadly poisonous in large quantity and, indeed, there are records of dogs dying after biting a toad. However, these occurrences are unintentional on the part of the toad so do not qualify in the category of what snakes or man-eating crocodiles are capable of.
Limited commercial value, an inherent inconspicuousness, and fear-provoking capabilities of some species all contribute to why reptiles and amphibians are poorly known and why herpetology is undertaught. Yet, ironically, the members of the groups, particularly some of the reptiles, hold a fascination for people that is unparalleled by most other members of the animal or plant kingdoms. Herpetology captivates us, perhaps, because for most people, even highly educated ones, any entry into the field is an adventure into the unknown.
90° in the Shade The University of Alabama Press
By Clarence Cason
Copyright © 1983 The University of Alabama Press. All rights reserved.