Eastern box turtles.
I’ve seen several of these unobtrusive critters in the past month, so I ought to spend a moment talking about them. We’ve had quite a bit of rain here lately, and turtles move more after rain.
Box turtles are easily identified by their high, domed carapace (top shell). The plastron (bottom shell) has a unique feature: a hinge. When threatened, all terrestrial turtles can pull their limbs and head in to gain protection from their shells. But box turtles go a step further by raising the hinged portion of the plastron, completely enclosing the head and front legs.
The box turtle looks and acts like a land-dwelling tortoise but is more closely related to pond turtles. You might see them in puddles or shallow creeks on occasion, but box turtles aren’t swimmers and can drown if they go in over their heads.
Box turtles are omnivores, eating grass, mushrooms, berries, earthworms, insects, slugs, and suchlike. Immature turtles tend to be more carnivorous, as young creatures often are – it’s the best way to get the protein they need to grow.
It’s possible to tell the sex of a box turtle with some basic observation. The male generally sports a brighter coloration than the female, although there is enough individual variation to make this method of sex determination unreliable. Male eyes tend to be red, while those of a female are brown; again, there is variation.
A more reliable method is to look at the back of the shell. The female’s shell is more domed and higher than the male’s. This may require looking at a few shells to get the hang of it, but it is an accurate method. Finally, if you have the turtle in hand, you will see the plastron of the male is somewhat concave, rather than flat as with the female.
Box turtles can breed anytime from late spring through early autumn. While there is courtship, they don’t bond, separating after mating. Most nests are produced in early summer. A surprising fact is that females can store sperm for several years, waiting for favorable conditions before developing eggs. When they are ready, the females dig shallow nests in the soil, deposit 1-8 eggs, and cover the nests in soil or leaves. They may lay more than one clutch in a season. Similar to other reptile species, temperature of the eggs determines the sex of the offspring. After two to three months, the eggs hatch and the hatchlings, perhaps an inch or two long, make their way into the world.
That brings me to the little tyke I saw last week. I noticed what looked like a dirt clod wobbling past my wheelbarrow. It was too small to close its shell (which was too thin to give much protection anyway); for the first few years, not being seen it its best defense. After inspecting it for a few minutes, I removed the wee thing from the wide open clay yard to the safety of the leaf mould just off in the woods.
Will it make it through the winter? Between predators, fire ants, and inclement weather, the first year’s odds are stacked against a young box turtle. If it reaches maturity (5-10 years), the turtle is likely to keep going for decades with few worries outside human-related mortality. I’ve seen turtles killed by plows, dogs, and cars; on hot summer days, it’s possible for a turtle to cook to death trying to cross an asphalt road. But if it avoids the hazards and finds enough slugs and bugs, perhaps our paths will cross in a decade as it searches for a like-minded turtle to tryst with.
If you wander the hardwood forests, you may come across an empty box turtle carapace. Perhaps, like this example, your shell is shedding its keratin and leaving only bone. Did the turtle leave its shell to grow a bigger one, like a snake shedding its skin? I’m afraid not. Look inside; you will see the structure of the backbone along the inside of the dome.
The bones extending from this structure are the modified ribcage, fused together into a protective dome. A turtle can no more leave its shell behind than you can pull loose from your skeleton!
For budding naturalists, box turtles are excellent creatures to experience up close. Spiders and snakes can be off-putting; birds, rabbits, and deer only allow a distant viewing. Even water turtles will slide off their logs when approached. But a box turtle is pretty mellow. It will sit, wary but confident of its defenses, while you observe. I met an environmental educator this week who said she likes to show kids the box turtle because it is the animal they are most likely to encounter in their backyards. “To these kids,” she said, “box turtles are nature.”