Rodents running rampant
By Callan Bentley
Flat Hat Variety Editor
When I went to Boy Scout camp, we stored all our food in a "chuck box," a large wooden trunk standing three feet above the ground in the center of our campsite. The reason for the chuck box was partly organizational (keeping everything food-related in one place) and partly protective (keeping raccoons from eating our grub).
One summer, though, we opened the chuck box every morning to discover that something new had been torn into and ripped apart. The oatmeal, perhaps, or maybe our supply of napkins. We scouts took turns blaming one another, but we soon discovered the actual culprit. When we opened the chuck box one morning, a small gray mouse ran for cover behind the Bisquik.
I'm not sure how familiar you are with the Eager Young Boy Scout mentality, but when we saw a mouse in our chuck box, we instinctively knew what had to be done. "Catch it!" someone cried, and the chase was on.
The mouse was a wily one, though. While we were searching for it among the silverware and spices, it made a successful and undetected escape to the ground below. Unfortunately, with a crowd of scouts lunging into the chuck box above, the ground was a danger zone. There were lots of shuffling feet. I felt something squish under my boot. Oops - I had killed the mouse by accident. Guiltily I took the mouse over the "Mammal Study" merit badge instructor. I figured he could use it as a prop in his lessons. Instead, I later heard that he roasted and ate it on a dare.
Such are the joys and vicissitudes of life at Boy Scout camp.
Mice are rodents, and rodents are everywhere. According to Peter Hanney, author of Rodents: Their Lives and Habits, "The rodents, without any doubt, are the most successful of modern mammals, with regards to both numbers of species and of individuals."
Rodents include among their legions mice, rats, voles, moles, shrews, lemmings, squirrels, beavers, chipmunks, and the capybara of South America. The capybara weighs a hefty 50 to 60 pounds, making it the world's largest living rodent. When considering non-living rodents, however, the Biggest Rat award would go to an extinct relative which was the size of a bear.
Hanney writes that, currently, 1650 species of rodents live on the planet, while the Audubon Society Field Guide to North American Mammals puts the number at upwards of 3,000. Whatever the number, rodents constitute roughly 40 percent of all mammalian species.
Being so numerous, rodents have a large effect on both the natural world and on man.
"They create a formidable force influencing the environment," Hanney writes, "both in their every-day behavior and as a source of food for carnivorous birds, reptiles, and other mammals."
Rodents have large eyes that bulge out from the sides of their heads, enabling them to scan a wide area for potential dangers. This may also help them see at night, as the majority of rodents are nocturnal. The order Rodentia derives its name from the Latin word rodere, meaning "to gnaw." All rodents possess several large pairs of incisor teeth in the fronts of their mouths.
Because the incisors ("buckteeth") are enameled on the front side only, the working of upper teeth against lower ones wears away the softer inner surfaces more rapidly. This produces a sharp, beveled edge ideal for gnawing. And gnaw they must, for a rodent's teeth grow continuously through its life. If it stops gnawing, the teeth will grow unchecked, and will eventually be so long that they curve back and pierce the animal's skull.
Rodents have no canine teeth, and there is a gap between the incisors and the cheek teeth. This gap, the diastema, enables the animal to draw in the sides of its lips so it can gnaw without getting chips of the material in its mouth. Effectively, then, gnawing takes place outside the mouth, while chewing occurs inside. This is an especially important adaptation for the muskrat, which frequently has the need to gnaw at things underwater. Without the diastema cheek-suck maneuver, submarine gnawing would result in a drowned muskrat.
Many of the larger rodents have semi-aquatic habits. Keep your eyes peeled for the following animals on your natural forays around Virginia's waterways:
Muskrats (Ondatra zibethicus) measure up to 24 inches long with a vertically flattened tail. Excellent swimmers, muskrats make their homes in lodges similar to those of beavers.
Nutria (Myocastor coypus) grow up to 55 inches long and have dark orange incisors and a round tail. Nutria are common sights along marshes, ponds, and streams.
Beaver (Castor canadensis)
are more recognizable by their horizontally flattened tail than by their size
(up to 46 inches). Lake Matoaka hosts several beavers. Just this past weekend,
I happened across a beaver dam across one arm of the lake. Canoeing or kayaking
around the shoreline will being you face to face with several beaver lodges.
Pay your local rodent a social call!