Missouri's Two Box Turtles
If wildlife were to compete in popularity contests, reptiles would probably lose. People naturally find furred or feathered creatures more appealing.
Box turtles are perhaps the one exception. People who'll recoil from other reptiles will take to box turtles. They are non-threatening; even their eyes have a responsive quality compared to the cold, unnerving stare of snakes.
Box turtles even have qualities we admire, such as the persistence and perseverance of the famous tortoise in Aesop's Fable.
We've heard the adage, "If it ain't broke, don't fix it." Mother nature seems to have applied this principle to turtles. The fossil record tells us that turtles have been on earth some 200 million years, and in that time have changed little. Box turtles won't win any races. But then again, if you've been around for a couple hundred million years, why hurry?
Box turtles differ from other turtles in several ways. They are terrestrial (land-dwelling) turtles. Their high, domed shells and unwebbed feet are adapted for life on land, not water.
But to discover the unique feature from which box turtles get their name, you have to turn them over. The bottom shell, known s the plastron, is equipped with a hinge. This hinged shell permits box turtles to close their lower shell against the inside edge of the upper shell (called the carapace). The turtle's head, tail and limbs are pulled inside - as if enclosed in a box.The three-toed box turtle is a land-dwelling turtle; its domed shells and unwebbed feet are adapted for life out of the water. The box turtle's hinged bottom shell (left) allows it to retreat inside the shell as if enclosed in a box - hence the name box turtle.
Missouri is home to two species of box turtles:
The three-toed box turtle (Terrapene carolina triunguis)
is found statewide, excluding the northwestern corner and extreme
northern Missouri. Adult thee-toed box turtles are 4.5 to 6 inches
long (115-145mm). - Three-toed box turtles, as their name implies, typically have three hind toes - but some individuals have four. They are a forest species, although they may also be found along forest edges and brushy fields. They consume earthworms and insects, but adult three-toed box turtles tend to be more vegetarian, eating a variety of plants, berries and mushrooms. This is the common box turtle of Ozark woodlands.
The ornate box turtle (Terrapene ornate ornate) is
a smaller (four to five inches), more colorful box turtle. Its
Missouri range includes all but the Bootheel. While ornate box
turtles sometimes share the same habitat as three-toed box turtles,
they have different needs. - The ornate box turtle prefers more open country: pastures, prairie and open woodland. Although ornate box turtles consume some plant matter (especially berries), 90 percent of their diet is insects - made up mostly of grasshoppers, beetles and caterpillars.
Three-toed Box Turtle
Underside of a three-toed box turtle
Easily distinguished from young three-toed box turtles by the color pattern on the bottom of the shell which is similar to that of the top.
The differences between a young three-toed box turtle and a mature turtle are obvious, easily visible to people as well as to other turtles. Changes in color, wear and size are gradual and can vary tremendously among individuals.
Portraits
In both species, adult male turtles can generally be identified
by their more colorful heads and forelimbs, a slight depression
in the plastron and bright red eyes.
The patterns of color on the head and neck of box turtles vary with age and from turtle to turtle. While the head color ranges from yellowish-brown to blackish-brown, it may be patter end with black, white, yellow or orange.
In general, males have irises of some shade or red, with mottling of yellow, white, purple or purple-own. Females generally have brown irises, which may be solid, or splotched or ringed with yellow, gold, orange, blue, pale red or purple. The combination of eye color and facial mottling is so variable, it may be distinctive to each turtle.
How old is it?
Like counting tree rings, annual growth rings on every scute of the turtle shell can help age young turtles. Unfortunately, these rings become smooth and hard to count with age. Growth rings are easy to count to age 5, but by the time the turtle is 15 years old the growth rings have been obscured by wear. The bottom (or plastron) of the shell may even have a polished appearance. precise aging of wild turtles is difficult. These are three-toed box turtles.
A close examination of each individual plate (or scute) of a box turtle's shell can reveal the turtle's age. Box turtles exhibit growth rings on each scute similar to the annual rings of trees; one ring equals one year's growth. On young turtles up to 10 years old, the rings are conspicuous and easily counted.
However, older turtles gradually wear these rings smooth. A turtle with a completely smooth lower shell with no visible growth rings can be estimated to be at least 30 years old.
Just how long box turtles live is uncertain. Estimates range from 32 to more than 80 years. Three-toed box turtles of over 50 years have been documented with certainty a number of times Estimates of box turtles living more than 100 years are probably not accurate.
The life of a box turtle:
Most box turtle mating takes place in the spring. Two to eight white eggs are laid in the spring or summer. Young turtles hatch in two to three months; however, some clutches laid in summer may not hatch until the following spring.
Hatchling box turtles, slightly more than one inch long, are vulnerable. They are secretive and seldom encountered.
Good box turtle habitat may have surprisingly high population densities of up to 10 or more turtles per acre. Box turtles are usually homebodies with small home ranges of about two to five acres. However, some turtles do travel. These are the turtles that drivers encounter crossing roads in the spring.
Research has shown that road-crossing box turtles are typically young (not yet sexually mature) turtles or young adult male turtles. Adult females and older males make up but a small percentage of these wanderers.
Box Turtles
So the question, "Why does the box turtle cross the road?" can be answered two ways. Immature turtles are establishing their own home ranges - wanderlust, in other words. Young adult male turtles are out looking for mates - just plain lust, you might say. Unfortunately, many thousands of these wanderers are killed by vehicles.
While some collisions red unavoidable, drivers who watch both the road and their speed can spare box turtles. Remember, if you see one turtle crossing the road, you'll likely encounter more. The main cause of mortality in adult box turtles, other than vehicles, are sudden freezes early or late in the year.
Box turtles are often victims of their own popularity. Many are captured and brought home as pets only to die from improper care. This is particularly true when box turtles are kept through the winter months.
The next time you encounter a box turtle in the woods, pick it up. A close look can reveal a lot about an individual turtle. See if you can determine if it is male or female, a youngster or and old-timer.
Look around a few hundred yards in each direction. The turtle in your hand may live for decades and near venture beyond what you see. Then put it down and let it slowly go on about its life.
Box turtles don't need much from us. By simply leaving them alone and keeping our eyes on the road, we can help ensure that these popular reptiles will continue to have a place in Missouri's outdoors for a long time to come.
