As pretty much everybody who lives in eastern North Carolina knows (unless they’ve been on an extended vacation in Cozumel), we had had a cold snap a few weeks ago that beat anything most of us have ever seen.
For four continuous days the temperature didn’t get above freezing and, at night, it dipped down to single digits. The Neuse, Trent and many other coastal rivers froze over and life in the outdoors seemed to come to a standstill. Or so it seemed.
A few days after Mother Nature loosened her icy grip a little, some hardy outdoorsmen suffering from bad cases of cabin fever ventured out. Two of them, both old friends of mine, came across something that shook their (and my) long-held otions of the world around us.
One fellow and some others broke the ice along the shore of Catfish Lake in Jones County and ventured across to a small cabin on the other side. There they came across a large cottonmouth moccasin. The ominous pit viper was a little slow-moving but frisky enough to curl up when approached, display its namesake facial structure, and let the human interlopers know they had better keep their distance.
On the same day, about fifty miles away on Harkers Island, another friend encountered another cottonmouth, also quite healthy and equally defensive. The man said he saw this one’s fangs extend from his upper jaw as they do when those snakes are preparing to strike.
How the heck did those critters – reptiles whose body temperature is controlled by the environment – survive a record-breaking cold spell, much less recover enough to be out and about when it was still frigid enough to freeze a brass monkey’s ears off.
According to Chris Kent, a biologist with the N.C. Wildlife Resources Commission, the answer to the first question may be “brumation.” That’s a process in which some reptiles respond to cold temperatures by burrowing under leaves, rocks, matted marsh grass or similar cover and hunkering down till things warm up a bit. During what is essentially a dormant period, their respiration and heart rate slow down drastically and they enter something akin to a comatose state.
Still it would seem that the day the cottonmouths were seen was cold enough that most folks would not expect a reptile to be out. John Pollard, a trained and licensed herpetologist from Carteret County, said that may be because of some unique characteristics of the species involved. He explained that water moccasins – cottonmouths – have the ability to puff themselves up with air (which explains why they are able to float high in the water) and they also have a thicker layer of fat than most snakes.
Those features act as insulators and may allow them to come out of brumation and seek a warm spot in the sun before their snakey and lizardly brethren.
Some other reptiles aren’t so well-equipped. Iguanas that are common in south Florida don’t seem to have the instinct for brumation. They will remain in their normal haunts – in trees along waterways and in people’s yards – even when the thermometer suggests they would be better off somewhere else. When it dips into the low forties, cold for that tropical clime, their metabolism sometimes slows down and, unable to maintain their grip on things, they topple to the ground.
Needless to say, that can be an exciting experience for a person walking under their tree at that moment. It can also be a thrill for anyone who picks one up and brings it inside. The iguanas are usually not dead, just stunned, and when they arm up they continue life as usual, which includes biting anyone messing with them.
Other wild animals have different ways of dealing with extremely cold weather.
They include hibernation, natural insulation, growing winter coats and feathers, conserving energy by moving very little, fattening up in the fall, huddling together and migration.
All of us, of course, learned at an early age that bears hibernate in the winter. That may be true for those in the northern parts of the continent but not for black bears in this region. According to Chris Kent, bears in these parts will find thick cover when cold weather approaches and burrow into it to wait things out. They never truly hibernate, however, and may be seen out feeding any day in the winter.
Being able to dine year around is one reason bears in this part of the country get very large.
Whitetail deer also find thickets that will offer some protection from wind and precipitation when things get tough and ride it out. Kent described deer as “unbelievably hardy.” They are helped in that respect in that they begin in the fall to develop thicker coats which consist of coarse, dark, hollow hairs that shed water and keep heat in. Foxes, coyotes and some other mammals are also helped by winter coats. Nearly all mammals build up extra fat in preparation for winter weather. (Some of us humans also do that).
Some semi-aquatic mammals such as beavers, otters and nutria don’t seem to be bothered by the cold much at all. That’s because they have dense fur close to the skin and slick, oily coats above that. Those animals seem to actually relish cold weather and can be seen romping in the snow or icy water any time.
Waterfowl may have the best way of dealing with low temperatures. They simply pack up and migrate south, continuing until they find food and cover to their liking. If they misjudge how fast and far they need to go, they still have a little built-in insurance. It’s a layer of fine, thick down close to their bodies with oily feathers over that to keep moisture out. In addition, the legs of ducks and geese don’t freeze when they sit in cold water because they are equipped with what is called “counter current circulation.” Arteries carrying warm blood from the heart are interwoven with veins bringing cold blood from the feet.
The result is that their legs stay warm enough to keep them working as they should.
Many upland birds and song birds stay warm when the temperatures drop by fluffing their feathers out to form dead air space – insulation – and huddling together. Bobwhite quail will roost as a covey, in a circle facing outward, to share their body heat.
We humans can learn a few things from our wild brethren. When things start getting chilly, we can’t grow a winter coat, but we can buy one or get it out of storage. And we can build up stores of fat to provide insulation, huddle together (with someone who doesn’t mind huddling), and perhaps migrate south. If we do the last, however, we do have to keep an eye out for falling iguanas.
Ed Wall can be reached at firstname.lastname@example.org or 252-671- 3207. His web site is www.edwalloutdoors.com