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Cross Timbers Wildlife News - Jim Dillard
October 2003



Jim Dillard is a Wildlife Biologist for Texas Parks & Wildlife. He writes from Mineral Wells TX.

Terrapene ornata ornata

Dry-Land Terrapins

My first experience with a dry-land terrapin was anything but "dry." I had encountered one crossing an old sandy road and as I picked it up, it clamed shut, drawing its head and feet inside its ornately decorated shell. As I held and examined it further, it unceremoniously emptied its bladder all over me, prompting me to put it down. I can assure you, the aroma of turtle water is not pleasant and tends to linger longer than you would like. Bobcats, coyotes and badgers learn this defensive tactic early on. It took me several turtles to remember to hold them at arms-length until they finish doing their "business."

The ornate box turtle (Terrapene ornata ornata) is found throughout Cross Timbers Country here in Northcentral Texas and as far north as South Dakota and east to western Indiana and western Louisiana. West of the Pecos River in Texas, it's replaced by the desert box turtle subspecies (T. a. luteola). Ornate box turtles have 5-8 yellow radiating markings on their second coastal scute (scutes are those plate-like structures that cover the top of the shell or carapace.) If you're looking at a box turtle head on, look at the scutes to the right and left of the center one located directly behind the head. On desert box turtles, these scutes have 10-16 radiating lines. Otherwise, the pattern on the other scutes of the carapace is a random series of radiating yellow lines on the dark olive to black background color of the shell.

The bottom part of their shell, called the plastron, is a yellowish ground-color with dark radiating lines. Unlike most species of turtles, a box turtle's plastron is hinged crossways with tough cartilage just forward of center. This allows both ends of it to move, enabling box turtles to draw in their head, limbs and tail when disturbed. Most would-be turtle-eating mammalian predators such as raccoons, foxes or coyotes aren't able to pry them open and move on to find an easier meal elsewhere. If left alone for a few minutes, they'll usually peek out to see if the coast is clear and then take off. Hawks and eagles use their hooked beaks to probe and snip open box turtles and persistent crows often peck them apart.

A box turtle's shell has a high dome without a prominent dorsal ridge but is slightly flattened on top and with a central yellow stripe. Their head, legs and tail are olive colored. Average shell length of mature adults is 4-6 inches. Heavily scaled forelegs support stout feet with clawed toes used for digging. They have four toes on their hind feet with the innermost toe and claw on each foot thickened and turned inward. This configuration helps them to hold their position during mating with the larger females. Males have red or orange eyes, whereas those of females are yellowish brown. Scales on the forelegs of males may also be red.

Ornate box turtles are adapted to dry country, and it's a good thing, considering the hot dry summers we've been having the past several years here in Cross Timbers Country. Their home range is usually about 5 acres. They're most active during early morning or late evening and especially after rainfall events. Like desert tortoises, they're able to store water in their urinary bladder and reabsorb it in times of need. In addition, they'll burrow down through loose sand or soil to find cooler conditions to escape the heat. They hibernate in burrows they dig or invade holes dug by other critters like badgers, skunks, or armadillos, making themselves at home whether welcomed or not.

Their diet includes insects such as beetles and grasshoppers, soft-bodies invertebrates (caterpillars, grubs and worms), berries, fruits, and carrion. I saw an ornate box turtle several years ago eating wild plums that had fallen on the ground under a plum-thicket without even puckering up, but then again, since turtles don't have lips, I guess that's not possible. I tried one: I puckered up! They've also been observed rummaging through cow patties looking for insects or other edibles.

Females dig shallow nests in sandy soil during May, June or early July. Here, she'll lay 2-8 oval 1 3/8 inches long brittle-shelled white eggs that incubate on their own for 60-70 days. I'm still looking to see my first elusive baby box turtle - I don't know where they go. They're most vulnerable to predation at this early age since their hinged plastron doesn't work until they're about half grown.

Although ornate box turtles can survive drought, predators and that old hot Texas sun, they're no match for automobiles and 18-wheelers flying down the highway at 70 mph. Slow and steady doesn't always win the race. Many are killed each year crossing our roadways here in Cross Timbers Country, just going about their business of living off the land. As our human population continues to grow here in Northcentral Texas, ornate box turtles and many other wildlife species are at greater risk for survival.

If you see an ornate box turtle trudging across the road, it probably wouldn't mind a little help getting to the other side. There's a good chance the next vehicle that comes along will smush it. Just remember, hold'um at arms length or you'll be holding a wet dry-land terrapin.

Until next time - I'll see you down the road and God Bless America!



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