What Do We Know About Coral Snakes?

Every spring I receive many questions about venomous snakes from people throughout the Southeast. Answers to some recent questions will be provided in this and next week's columns.

Q. I hear a lot about the danger of rattlesnakes and copperheads in the South but no one provides much information about coral snakes. Are they really different from the other poisonous species?
A. Snakes qualify as one of the world's most fascinating group of creatures with which virtually everyone is familiar. A snake on a playground will nearly always attract a bigger crowd than any bird, with the exception of, say, an ostrich or an albatross. People are intrigued with snakes of every size, in part because we know that some of them are potentially dangerous. Yet only six of the 52 species that occur naturally in the southern United States east of the Mississippi River are venomous. Of the remaining 46, all have teeth, and a few will bite if picked up but even these can be considered harmless.

To most people, the words "venomous" and "poisonous" are synonymous. The technical distinction is that venom is injected into the bloodstream; poison is typically injected or absorbed through mucous membranes. As far as I know, no snakes are poisonous to eat, although I have only tried a few so cannot speak with certainty about all of them. The copperhead, cottonmouth, and three kinds of southeastern rattlesnakes, all venomous, are known as pit vipers. The heat-sensitive pit is located between the nostril and eye. If you are using the presence of this pit to determine if a live snake in the woods is venomous or not, you are probably too close to the snake. The coral snake is distinguished from the pit vipers in several ways. Nonetheless, despite many people's misconception, coral snakes have hollow fangs in the front of the mouth with tubular connections to venom sacs located in the head, as do pit vipers.

Coral snakes are the only North American snakes in the cobra family. The type of venom they inject, generally referred to as neurotoxic, is distinctively different from that of most other U.S. snakes. The venom affects the nervous system and results in muscle paralysis. As the venom effect progresses through the body, the muscles of the diaphragm can become paralyzed, resulting in difficulty in breathing. If that difficulty continues, the result can be fatal.

From a human safety standpoint, southeastern coral snakes are small, rare, and unlikely to bite a person unless picked up, which no one other than a herpetologist should do. An accidental bite from an unseen coral snake is a truly rare event. The greatest likelihood of a coral snake bite is to a child who might pick up a brightly colored red, yellow, and black snake because it is pretty. The eastern variety, which is one of the 70 species of coral snakes found in the Americas, is found in the Coastal Plain from Louisiana to the Carolinas and throughout Florida.

Despite the potency of coral snake venom, a victim has plenty of time to get to a hospital. According to the book "Venomous Reptiles of the Western Hemisphere" (2004; Cornell University Press) even "the onset of symptoms usually begins during the first 2-6 hours following a bite" and "may require 48 hours to reach the maximum effect." Ample time would be available anywhere in the country to reach a medical facility.

I have firsthand knowledge of two eastern coral snake bites (to a young girl and an adult male); both of them had happy endings. Each person was bitten on the finger. Numbness and paralysis slowly progressed up the arm; the attending physician told me the man could not feel a needle stuck into his hand. When each victim was given coral snake antivenin, the process immediately reversed itself and the paralysis gradually disappeared. Why the man picked up a coral snake in the first place is a question he will now be able to answer for the rest of his life.

Send environmental questions to ecoviews@gmail.com.

Whit Gibbons is an ecologist and environmental educator with the University of Georgia's Savannah River Ecology Laboratory
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