Box Turtles in Southwest Florida
Question: We have several turtles living on our property. They are dark with yellow markings and we are wondering what they are?
Answer: From the detailed description that you sent in, you are dealing with a number of box turtles (Terrapene carolina). Box turtles are land turtles found in the eastern states. Two types of box turtles occur in Florida. The Florida Box Turtle (Terrapene carolina bauri) lives throughout Florida. This turtle is black with a distinct pattern of radiating yellow lines on its shell. The Gulf Coast Box Turtle (Terrapene carolina major) is another box turtle that occurs in Florida but is usually found in the Panhandle. This turtle has a dark carapace (dorsal part of the shell) with yellow or orange markings, but lacks the bright lines of the Florida Box Turtle.
The Florida Box Turtle is an attractive animal that makes a good pet. This has led to the over-collection of this animal. The Florida Box Turtle can no longer be sold commercially. This land turtle spends most of its time wandering through woods, fields and gardens. It will occasionally soak itself in water and is usually seen just after a rain crossing roadways. These land turtles get their name because they can fold themselves up like a box. All box turtles have a hinged plastron (ventral part of the shell) which allows them to close their shell almost completely.
The males are slightly larger than the females and have short, thick, curved claws. They also have longer and thicker tails than females. Unlike the Eastern Box Turtle (a close relative), the Florida Box Turtle has three toes on its hind feet instead of four. The Florida Box Turtle grows to about 11 cm by 8 cm in size. The yellow markings can also be found on the head.
The Florida Box Turtle is omnivorous. These critters eat snails, insects, berries, fungi, slugs, worms, roots, flowers, fish, frogs, salamanders, snakes, birds, and eggs. They have been seen eating carrion like dead ducks, amphibians, and assorted small mammals. Their food preferences vary with the seasons, but the young are mostly carnivorous as they grow during their first five to six years. Adults tend to be more herbivorous but do not feed on green leaves.
The box turtle begins to mate in the spring and continues this ritual through October. A female can lay fertile eggs for up to four years after one successful mating. Nesting occurs from May through July. Nests are usually dug in sandy soil. The eggs are then laid in the cavity and the nest is carefully covered up again. Three to eight eggs are usually laid and incubation takes about three months. The incubation time will vary according to soil temperature and moisture. The sex of the young is also temperature dependent. Nests that are cooler than 97 to 106 degrees F tend to be males, and those above 108 degrees tend to be female. Box turtles reach maturity at five years but continue to grow for at least twenty. Some box turtles are believed to live over one hundred years.
Box turtles usually have a home range of 250 yards but will occasionally travel outside of this boundary. Home ranges for each turtle overlap and they are often found together. They show no antagonism toward each other. If frightened they will retract their heads and limbs into their shell and clamp it shut until the perceived threat is gone. This defense technique protects adults from predators, but juveniles are still at risk. Box turtles help spread seed and eat some injurious insects. The downfall to having turtles in your yard is that they may damage some vegetable crops and destroy the eggs of nesting birds. These turtles are quite common and maintain a healthy population size. Enjoy watching them in your yard!
Shannon L. Ruby is the Natural Resources/Agriculture Agent with the University of Florida/IFAS and Lee County Extension Service. To submit questions, call 461-7515 between 9am and 4pm or send questions to 3406 Palm Beach Blvd. Fort Myers, FL 33916-3736 or via e-mail at firstname.lastname@example.org.