Common Box Turtle (Reptiles of Alabama)

Common Box Turtle

Terrapene carolina

Summary ⁷

The common box turtle (Terrapene carolina) is a species of box turtle with six existing subspecies. It is found throughout the eastern United States and Mexico. The box turtle has a distinctive hinged lowered shell (the box) that allows it to completely enclose itself. Its upper jaw is long and curved.

Biology ⁸

Common box turtles are predominantly terrestrial reptiles that are often seen early in the day, or after rain, when they emerge from the shelter of rotting leaves, logs, or a mammal burrow to forage. These turtles have an incredibly varied diet of animal and plant matter, including earthworms, slugs, insects, wild berries (2), and sometimes even animal carrion (4). In the warmer summer months, common box turtles are more likely to be seen near the edges of swamps or marshlands (2), possibly in an effort to stay cool. If common box turtles do become too hot, (when their body temperature rises to around 32° centigrade), they smear saliva over their legs and head; as the saliva evaporates it leaves them comfortably cooler. Similarly, the turtle may urinate on its hind limbs to cool the body parts it is unable to cover with saliva (5). Courtship in the common box turtle, which usually takes place in spring, begins with a 'circling, biting and shoving' phase. These acts are carried out by the male on the female (4). Following some pushing and shell-biting, the male grips the back of the female's shell with his hind feet to enable him to lean back, slightly beyond the vertical, and mate with the female (6). Remarkably, female common box turtles can store sperm for up to four years after mating (4), and thus do not need to mate each year (6). In May, June or July, females normally lay a clutch of 1 to 11 eggs into a flask-shaped nest excavated in a patch of sandy or loamy soil. After 70 to 80 days of incubation, the eggs hatch, and the small hatchlings emerge from the nest in late summer. In the northern parts of its range, the common box turtle may enter hibernation in October or November. They burrow into loose soil, sand, vegetable matter, or mud at the bottom of streams and pools, or they may use a mammal burrow, and will remain in their chosen shelter until the cold winter has passed (4).