ORNATE BOX TURTLE, (Terrapene ornata), (AGASSIZ, 1857)
IDENTIFICATION: 4-5 inches (10-12.5 cm). The coloration and markings present on the carapace, plastron, head, and limbs can be highly variable from one population to the next. However the typical base coloration of the carapace is olive brown to dark reddish brown. A yellowish mid-dorsal line is also present on the keel-less carapace. The carapacial scutes are further ornamented with anteriorly directed lines radiating from the center of each scute. Once again, this species demonstrates some polymorphism and the carapacial stripes may vary from bright to creamy yellow to almost white.
The plastron is longer than the carapace and has two closeable lobes between the pectoral and abdominal scutes. The closure of the plastron is accomplished via a plastral hinge. The plastral hinge is located near the fifth or sixth marginal scute. This allows for complete closure of the shell when the turtle is alarmed. The markings and coloration of the plastron are also variable from one population to the next. It also has a pattern of radiating lines present on each scute. The plastron may have a basal coloration of creamy yellow with black radiating lines. The exact opposite may be true as well, with an almost black plastron and yellowish radiating lines on each scute.
The coloration of the skin may be creamy white with a light suffusion of olive green to beige and a yellowish mid-dorsal stripe is usually present on the tail. The scales present on the anterior portions of the limbs bear the strongest coloration. Red, orange, yellow, or a combination of these hues adorns the front of the fore and hind limbs as well as the feet. Yellow spots may be present on the head or the head may be predominately a dark olive green to greenish yellow. The coloration of the beak may also vary from creamy yellow to the color of the head.
The "desert" or "western" box turtle (T. ornata luteola) is fairly easy to distinguish from its eastern relative. The western box turtle typically has 11-14 narrow lines present on the second costal scute. As individuals of this race mature, their carapace becomes more uniform and less distinctively marked. The coloration of the carapace is olive to horn brown and most individuals have a bluish-green head.
ECOLOGY AND BEHAVIOR: Throughout most of their range ornate box turtles may be active from March to November. Their activity, of course, is largely dictated by weather events and climatic factors. Ornate box turtles are most commonly encountered during the spring months after the first heavy thunderstorms. Their springtime activities begin to slow down by June when warmer temperatures and less frequent rains prevail.
During the hot months of late June to September ornate box turtles aestivate below the substrate or in other suitable refugia. I have found specimens during the oppressive summer heat sitting in shallow pools of water beneath limestone shelf formations. At the time of this observation this retreat was also utilized by Rio Grande leopard frogs (Rana berlandieri). Other ideal sites for relief from the heat may include preexisting burrows such as those dug by mammals. The heat inspired dormancy is halted after heavy summer thunderstorms. This is especially notable in the western portion of the range when summer monsoons drench the parched ground and revive the dormant turtles. In the spring months, ornate box turtles are found in the morning, afternoon, and early evening. In the past ten years, I have only found two specimens active at night. These were both seen on the road during a thunderstorm in Tarrant County, Texas. After spring thunderstorms in central Texas, I have witnessed several specimens entering the roadway. Many of these had cow manure adhered to their carapaces. It is likely that the fresh cow manure offered the turtles a suitably humid retreat and a location for invertebrate prey items.
When the oppressively hot summer temperatures arrive the activity of box turtles becomes more restricted to the cooler morning and late afternoon hours. The seasonal variance in activity rates also corresponds with activity displayed by captive specimens. However captive specimens tend to be more active throughout the year except for the winter. This of course is attributed to the keeper providing fresh water and food on a regular basis. This can result in the turtles "knowing" when to expect their food and water. Ornate box turtles quickly become accustomed to their feeding and watering schedules. Undoubtedly the antics displayed by captives during such interactions between keeper and kept have endeared them to many. In fact one keeper sent me videotape footage and photographs of his turtle raising up and resting on his hind limbs to "beg" for food. (David Hirsch, personal communication). Despite any anthropomorphic interpretations that may be derived from such actions, it is most likely a habit the turtle developed while in the wild. Possibly, this specimen learned how to obtain hard to reach foods in this manner. Despite their seemingly pleasant interactions, in captivity there are occasionally belligerent specimens. These are typically males that view other males as competition for available females and or food.
Courtship begins with males pursuing females and nudging the margins of their shells. The nudging is then followed by the male rapidly moving the first half of his plastron on top of the female's carapace. One observer noted a male emitting a white stream of fluid from his nostrils during such an episode (Brumwell, 1940). Once intromission ensues pairs may remain copulating for 30 minutes to two hours. Pairs will often remain in a copulatory position for a great deal of time following coitus. Males grip the females just beneath their legs and the fleshy areas on the gluteal region of their hind legs with the first claws of their hind feet. The remaining claws are used to help secure a grip to the female's plastron. Females help secure the coital positioning by wrapping their hind legs around those of the male. (Legler, 1960).
The elliptical eggs often measure 21.7 X 36 mm with a mass of 10g. Laboratory experiments involving hatching rates and different air temperature resulted in eggs hatching between 56-127 days. Eggs maintained at temperatures of 91° F (33° C) had an average incubation period of 59 days, at 82° F (28° C) 70 days, and at 75° F (24° C) 125 days (Legler, 1960). Eggs incubated at 84° F (29°C) resulted in females while 96% of those incubated at 77° F (25° C) produced males.
Hatchlings are typically 30 mm in carapace length with a mass of 7 grams. They often emerge during the late summer and early fall (August to October). However, hatchlings found in March and April indicate that this species may remain underground in the nest chamber after hatching in order to emerge during more favorable spring like conditions.
Ornate box turtles are chiefly carnivorous, although captive specimens consume a wide variety of food items from meats to vegetables. During a field study in Kansas, ornate box turtles were observed consuming the following: beetles, earthworms, caterpillars, grasshoppers, fish, a dead wood rat, snails, cantaloupes, tomatoes, strawberries, blackberries, green bean pod, a dandelion and even one specimen has been found stuck in a can of honey. Whether this specimen was seeking the honey or bees that were attracted to it is unknown (Metcalf and Metcalf, 1970). Other documented food items eaten in the wild include: a recently killed black rat (Rattus rattus), bird carrion, a land snail, June beetle, persimmons, stick insect, mulberries, prickly pear cactus, and cow dung (Blair, 1976). The affiliation this species seems to have with cow dung is quite significant, as dung beetles can supply a considerable amount of the turtle's diet (Ernst, et al. 1994). It is interesting to imagine what type of herpetological communities were present when millions of bison roamed the North American plains.
GEOGRAPHIC DISTRIBUTION: The western subspecies (T. ornata luteola) occurs in southeastern Arizona, southern New Mexico, west Texas, and into northern Mexico including Sonora and Chihuahua. The eastern subspecies (T. ornata ornata) has a wider distribution which includes eastern New Mexico and Texas to southern South Dakota, southwestern Wisconsin, western Indiana, and southwestern Louisiana (Iverson, 1992).
Blair, W. F. 1976. "Some aspects of the biology of the ornate box turtle, Terrapene ornata." Southwestern Naturalist. 21:89-103 .
Ernst, C. H., J. E. Lovich, and R. W. Barbour. 1994. Turtles of the United States and Canada. Smithsonian Institution Press.
Iverson, J. B. 1992. A Revised Checklist with Distribution Maps of the Turtles of the World. Earlham College. Privately printed; Richmond, Indiana.
Metcalf, E. L., and A. L. Metcalf. 1970. "Observations on ornate box turtles (Terrapene ornata ornata, Agassiz)." Trans. Kansas Acad. Sci. 73:96-117.
Minton, S. A., Jr. 1972. "Amphibians and Reptiles of Indiana." Indiana Acad. Sci. Monograph. 3:1-346.
Wilbern, S. E. 1982. "Climbing ability of box turtles." Bulletin of the Maryland Herpetological Society. 18:170-171.