Friday, May 17, 2013

Bike Biology: Copperhead Road

This past week it seemed that copperheads awoke from hibernation on cue. Agkistrodon contortrix is the most widely encountered venomous snake in North Carolina.

Several roadkill were reported on the Raleigh 400km brevet. The lead-in photograph (roadkill), courtesy of Sridhar, was snapped on a recent populaire. The second photo (live) was taken on a commute by MikeO.

Both photos capture nicely the two attributes of poisonous snakes with which everyone ought to be readily familiar, while viewing from a safe distance. First, note the thick body of both snakes. The second characteristic of local venomous snakes is the telltale, arrowhead-shaped head.

Unlike venomous rattlers and water moccasins, whose first instinct at the sign of danger is to slink away if given the opportunity, the modus operandi of copperheads is to strike first.

An expert on copperheads, Whitt Gibbons, professor at the University of Georgia, notes:

Most copperheads tested have struck out immediately when they felt threatened. This behavior explains why more people receive legitimate snakebites from copperheads than from any other species of venomous snake in North America. The copperhead's initial threat display is to strike. It lashes out at an enemy as a warning. If the enemy is close enough, the fangs may penetrate the skin.

Here is a short video of a copperhead in its natural habitat.

If there is any good news regarding copperhead bites, it is that copperhead venom is not as potent as that of other poisonous snakes indigenous to our state. Nor do copperheads inject as much venom with their first strike as other snakes. Even so, sufficient venom is released to cause abundant tissue swelling. Thankfully, copperhead bites are rarely lethal. Full recovery, often without tissue death, is common. None of this, however, lessens the real pain and suffering of those bitten by copperheads.

The reader will be interested in a first-hand account by one of our local randonneurs, Jerry Phelps, who was bitten a few weeks ago by a copperhead at night in his driveway, while loading luggage into his car. The copperhead was under the car bumper. Jerry says that he may have stepped on the copperhead, which, nonetheless, had had ample opportunity to move away. Jerry recalls:

According to the EMTs and what I read afterwards, young (ie small) snakes do not have the ability to inflict a “dry bite.” They inject the full dose of venom. And a small snake bit me.—BTW, the shoulder-less scoundrel is still alive as far as I know! I didn’t have any tissue necrosis, just massive amounts of swelling. I was bitten on the instep of my right foot and my foot and leg swelled to slightly above my knee—my ankle was so swollen, I couldn’t flex my foot. It was very painful and difficult to bear weight on until about three days after the bite. It took about three weeks for the swelling to completely go away, but I was back on the bike about 10 days after the bite. I was also told that the anti-venom can be more harmful and dangerous than the venom itself. It is also very expensive, as much as $5-8,000 per dose. Therefore the recommended treatment is to monitor the patient’s vital signs and for signs of shock, treat for pain, and blood tests for hemotoxic shock. 

I was not given antivenom but was given Dilaudid—a powerful opiate. Two IV doses of morphine did nothing for me. I was in the ER about 8 hours and was sent home with an antibiotic and oxycodone. And I was given a tetanus booster in the ER. I’ve had no ill effects at all since.

While North Carolinians lay claim to “Tobacco Road,” it seems that Tennesseans have a corner on “Copperhead Road.” The name of a now-classic ‘80s country rock song, Rolling Stone called “power twang,” that embraces local history.

Please watch your step!

Let’s ride!


skiffrun said...

thanks for informative post, Dean.

-b said...

Very timely, Dean -- I nearly stepped on a baby copperhead in the back yard a week or so ago. BTW, Davidson Univ. has a great on-line guide for identifying snakes (as well as other reptiles & amphibians):