Art Lander’s Outdoors: Eastern box turtle, docile, colorful turtles are joy to encounter

The eastern box turtle is present throughout Kentucky, but most often found where there is a mixture of forestlands and overgrown fields, with moist underbrush around springs, seeps or small creeks.

Shell shape and coloration is highly variable. In fact, there are four subspecies found in the U.S. The subspecies found in Kentucky is Terrapene carolina carolina.

Eastern box turtles have a sharp, horned beak, stout limbs, and their feet are webbed only at the base. They have a high domed carapace (shell) and five toes on each front leg. Normally they have four toes on each hind leg, although some individuals may have three toes on each hind leg.

When frightened or harassed, box turtles retreat into their shells. A hinged lower shell (plastron) enables the turtle to completely close up, protecting its head and legs from predators.

The eastern box turtle’s shell can be of variable coloration, but is normally brown or black with a yellow or orange radiating pattern of lines and spots. Skin coloration, like that of the shell, is variable, but is mostly brown or black with some yellow, orange, red, or white spots or streaks.

Males normally have dark orange or red eyes, while the females’ eyes are typically brown or light orange.

The female’s plastron (lower shell) is flat, while the male’s is concave so he can fit over her during mating.

Males also have more colorful markings on their forelegs, and the claws on the hind feed are shorter and more curved than those on the females.

When injured or damaged, the shell has the capacity to regenerate and reform. Keratin slowly forms, growing to replace damaged or missing scutes (bony plates). Over time, the damaged area falls off, revealing the new keratin formed beneath it. Unlike water turtles box turtle scutes continue to grow throughout the turtle’s life and develop growth rings.

An adult eastern box turtle measures about four to six in length, but occasionally reaches over seven. They are very long-lived, commonly reaching 30 to 40 years of age in the wild.
 
Their home range is very small, about 300 yards in diameter. In cold climates they hibernate through the winter in loose soil at a depth up to two feet.

Geographic Range

The eastern box turtle is found as far north as southern Maine and Michigan’s Upper Peninsula, south to southern Florida and west to eastern Kansas, Oklahoma, and Texas.
 
In the northern parts of its range, box turtles are rarely found above 1,000 feet in elevation, while they may be found up to 6,000 feet in the southern parts of their range.

Distribution in Kentucky

Eastern box turtles are found statewide.

According to the Kentucky Department of Fish and Wildlife Resources there are 56 species of reptiles in Kentucky, including 10 lizards, 32 snakes, and 14 turtles. All but one of Kentucky’s turtles are aquatic and leave the water only to make overland migrations between water bodies or to lay their eggs.
 
The eastern box turtle is the only totally terrestrial species, but it will venture into shallow water, soaking for a time in puddles. During the hot periods turtles may burrow into mud for days at a time.

Food Habits

The eastern box turtle is an omnivore, eating both plants and animals. Hatchlings are primarily carnivorous. But as they grow their diet shifts more towards plants. Eastern box turtles feed on earthworms, snails, slugs, grubs, beetles, caterpillars, grasses, fruit, berries, mushrooms, flowers, and even carrion. 

Interestingly, box turtles are even able to eat many mushrooms that are toxic to humans.

Population Decline

Population monitoring across the U.S. indicates an ongoing gradual decline of Terrapene carolina that probably exceeds 30 percent over the past 50 to 100 years.

Causes of decline are not fully understood, but several factors are responsible, including habitat destruction, pollution and pesticide effects, and direct mortality from vehicles on roadways and tractors in farm fields. There has also been a spike in predation of eggs and juveniles, primarily by raccoons, coyotes, skunks, opossums and crows, causing decreased recruitment.
 
The capture of turtles for the international pet trade, which peaked in the 1980s and early 1990s, impacted populations, too. Exports ceased in 1994 when genus Terrapene was included in the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), an agreement created to ensure that international trade in specimens of wild animals and plants does not threaten their survival.

Reproduction

Female box turtles are able to store sperm in their oviducts for up to four years and are thus able to produce viable eggs for many years following a single mating.

Box turtles mate between May and October. Eggs are laid into oblong holes that are three to four inches deep. The holes are meticulously dug by the female into the soil on a sunny, warm site.
 
Three to six elliptical, leathery eggs are laid and then covered to incubate and then hatch on their own. Several clutches can be laid per year. Incubation lasts about 75 days.
 
A clutch that hatches late in the season may over-winter in the nest hole and emerge the following spring. Young are about one and one-quarter inches long when they hatch.

The docile, colorful turtles, are a joy to encounter. For generations they have captured the imagination of Kentucky farm boys and girls, in touch with the natural world.

Art Lander Jr. is outdoors editor for NKyTribune and KyForward. He is a native Kentuckian, a graduate of Western Kentucky University and a life-long hunter, angler, gardener and nature enthusiast. He has worked as a newspaper columnist, magazine journalist and author and is a former staff writer for Kentucky Afield Magazine, editor of the annual Kentucky Hunting & Trapping Guide and Kentucky Spring Hunting Guide, and co-writer of the Kentucky Afield Outdoors newspaper column.