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Nature’s Ways: The Long-Lived Eastern Box Turtle

Mark Nale

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A gray squirrel or cottontail rabbit would be lucky to see its second birthday. A white-tailed deer is very old at age 10, and a rare black bear lives to 20. However, eastern box turtles can have a long lifespan — very long. Although no one knows exactly how long, many box turtles live to 40 or 50 years, and a few have been reported to be over 100.

The eastern box turtle (Terrapene carolina) is totally terrestrial. It has a highdomed shell that is usually brown and decorated with orange or yellow markings and it is the only central Pennsylvania turtle with a hinged plastron (the bottom of their shell). The easiest way to identify a box turtle is by picking one up. When danger threatens, its head and legs can be completely hidden when the double-hinged shell closes, often accompanied by a very noticeable hissing sound.

The box turtle is one of 14 species of turtles that live or have lived in Pennsylvania. Two species, the eastern mud and the midland smooth softshell, have disappeared from the Keystone State due to loss of habitat. Three others, the bog turtle, the red-bellied turtle and the Bandling’s turtle have threatened or endangered populations here.

The eastern box turtle inhabits forest, pasture, reverting fields and parks.

It is found in all 67 of Pennsylvania’s counties, but it is least common in the extreme northern edge of the state, as well as in totally urbanized areas. Even though Pennsylvania’s population of box turtles has been declining for several decades, it remains one of the state’s most common turtles.

Habitat is the key for protecting turtles, as well as for deciding which one is most numerous. Depending on where you live or have lived, and the type of outdoor activities you partake in, different people might name different species of turtle as what they think most common.

As a child, I spent a lot of time playing in and near two small streams in Blair and Bedford counties. As I grew older, I did less playing and more fishing in those same two streams, as well as other similar waters. By far, the turtle that I spotted most often was the wood turtle, therefore I assumed wood turtles to be most numerous.

If you spend a lot of time around ponds or slow-moving rivers, you might pick the painted turtle as most numerous. However, the most common turtle in Pennsylvania is likely the box turtle.

I found out just how numerous box turtles were when my son adopted an Irish setter puppy. That first summer, the pup roamed the woodland adjacent to my Centre County home and was always locating and retrieving box turtles and dropping them harmlessly in my yard. At one point I remember seeing four in the lawn at once. Fortunately, turtle collecting was a passing puppy fad.

Each section of a turtle’s shell (called a scute) grows a new ring every summer, just like a tree. You can count the rings to age a young turtle, but after 15 years, the older rings are often worn smooth. Box turtles grow at an average rate of just over a third of an inch annually, to attain a shell length of about six inches in 18 to 20 years.

Box turtles are omnivorous, eating both plant and animal material. Younger turtles eat more animal matter (carrion, insects, snails and slugs), while older box turtles are believed to feed mainly on berries. They seem to particularly relish ripe raspberries, strawberries, dewberries, blackberries and slugs.

Male box turtles have a concave surface on their plastron to facilitate mating, and they usually have red eyes. Females have a flat plastron and yellow or brown eyes. They are sexually mature at about six years of age.

Female box turtles bury their leather-like shelled eggs in sandy soil and give no care to their young. Mating can occur during any warm month, but they usually lay their eggs in June. Hatching time varies greatly and depends on soil temperature.

Box turtles remain active during the summer and early fall, but cooler weather eventually will stimulate these cold-blooded reptiles to seek a safe spot for the winter. Hibernation sites for box turtles are located in soft soil under leaves or grass, rather than under water or mud like most turtles. Several turtles may spend the winter together and they are known to reuse the same sites.

Centre County just might be the home to the oldest box turtle ever discovered.

In 2012, Josh McCaulley, one of my former high school biology students, found a male box turtle in Taylor Township with 1878 carved in its plastron. I sent photos of the turtle and the engraving to three box turtle experts.

Although it was impossible to verify the date, they concurred that the date was carved in when the turtle was an adult (already at least 18 years old) and that it was indeed a very old turtle. If accurate, that box turtle was at least 152-years-old at the time.

Dr. C. Kenneth Dodd, a renowned box turtle expert with the University of Florida and author of “North American Box Turtles – a Natural History,” offered his opinion.

“The date of 1878 seems reasonable, especially considering the way that the carapace looks. I have seen only a very few such turtles that look like this,” he said.

“I suspect this is indeed a very old turtle that somehow has survived the onslaught of man. The appearance of the date — with no extensive spacing between the numbers and a similar height among numbers — suggests it was marked after the turtle reached maturity. If it was small when marked,” Dodd said.

It is best not to collect turtles. If one does, always return them to the exact spot of capture as soon as possible. Evidence suggests that because of their small home range, turtles released in strange areas may become disoriented and unable to locate enough food or a suitable hibernation site.