INTRODUCING THE EASTERN BOX TURTLE
My first encounter with an eastern box turtle occurred in the forested Trestle Pointe property near Fisherville. I was surveying the property for the first time when I nearly stepped on the cryptically colored, yellow and black domed shell (called a carapace). The legs and head were extended and its eyes were wide open. I crouched down to get a good look at it. Knowing it was not a snapping turtle, I reached down and picked it up. Within a few seconds its arms, legs, and head pulled in, and a conspicuous trap door in the front of the belly (called a plastron) sealed the animal fully inside the grapefruit-sized shell. Amazed, I turned it over and over as if examining a baseball, took some photos, and set it back where I found it.
The eastern box turtle (Terrapene carolina) is a remarkable and charismatic critter of the eastern forest. It is relatively common in some locales, including Floyds Fork—I have found perhaps 15 or 20 over the past couple years. There are four subspecies found in the eastern states; our subspecies occurs from southern Maine, to Michigan, to Georgia. Other subspecies occur in Florida, the Gulf Coast, and the Lower Mississippi states. There is also a western box turtle.
Eastern box turtles bury themselves in the soil in autumn and emerge around March. The territory of a box turtle is a few hundred square yards up to a few acres. Better habitat will allow a turtle to keep a smaller territory.
As a generalist, box turtles eat a variety foods; this has probably allowed their success during the dramatic landscape changes in Eastern North America over the past few centuries. Box turtles are omnivorous eating snails, slugs, caterpillars, spiders, snakes, eggs, and carrion as well as fruits and berries. The fruits of our native plants are particularly important for box turtles and box turtles are important for the plants; the seeds of several species have better germination rates after passing through the gut of a box turtle. Such species include jack in the pulpit (Arisaema triphyllum), pokeweed (Phytolacca americana), black cherry (Prunus serotina), and grape (Vitis aestivalis). For mayapple (Podophyllum peltatum), the box turtle is the only known seed disperser and the seed germination rate exceeds 38% after passing through a turtle while it is only 8% for unpassed seeds.
For such a relatively small animal, box turtles are long-lived. Most sources suggest they live for 30 to 50 years in the wild though centenarians have been reported. Interestingly, one can obtain a reasonably accurate age of a box turtle by counting the growth-rings (like a tree) on the scutes (plates of the shell). I have aged Floyds Fork turtles to their mid-20s.
The shell can also be used to decipher the gender of a box turtle. In general, a female’s shell is more domed, while a male shell is somewhat flatter. Perhaps more diagnostic is a concavity occurring on the male plastron (belly) which allows him more stability when mating.
I have left all the box turtles I have encountered right where I found them. Unfortunately box turtles are often removed from the wild to become pets. Over half of these animals die in captivity. The numbers of turtles entering the commercial pet trade is staggering. In Louisiana, for example, 30,000 box turtles were removed from the wild to enter the pet trade over a three-year period. Undoubtedly, other states have similar (but undocumented) figures. Some states have passed legislation protecting the turtles.
Loss of habitat and fragmentation is the other factor leading to a loss of box turtles. Roads and particularly train tracks can present formidable barriers to a box turtle. Many turtles are killed by lawn mowers. Building greater connectivity among forest patches and rewilding our landscapes will help box turtle populations and all native flora and fauna.
A version of this Field Note was printed in The Courier-Journal in September of 2012. Click here to read the article.