Speaking of Nature

Kids & Critters: Eastern Painted Turtle

Last week, for the first time this year, I saw turtles sunning themselves out of the water. These were painted turtles and though they can sometimes be rather small, they were easy to see on Sunday because the light of the sun would shine off their shells. I was out for a walk with my family and we passed by many different ponds, each with its own set of turtles warming themselves in the sun.

Everybody knows that turtles have shells, but most people don’t know what the shells are. Turtle shells are actually the highly specialized bones of the backbone and rib cage. The top of the shell is known as the “carapace” and the bottom is called the “plastron.” You will also notice that the carapace is made of panels, kind of like the shingles on a roof. These sections are called “scutes.”

The scutes are not randomly placed or randomly shaped. For instance, there is a group of scutes running down the middle of the back that are known as “vertebral scutes.” Can you guess which bones in the human skeleton are homologous with these scutes? Not much of a mystery is it? Vertebral scutes are in the same position as our vertebrae.

Along each side of the vertebral scutes are others known as “costal scutes.” These are ribs that have flattened out and fused together for protection. In painted turtles, the vertebral costal scutes are black edged with olive-brown edges. The small scutes that form the outer edge of the carapace are called “marginal scutes” and are black with red stripes. These markings, along with the red and yellow markings on the head and legs, are what led to the name “painted turtle.”

The bottom of a turtle’s shell is called the “plastron.” The scutes on the plastron of the eastern painted turtle are yellow, but they are often stained a reddish brown in water that has a lot of tannins in it, so don’t be confused if you find a painted turtle with a plastron the color of tea.

But when they are very little, turtles have more than one shell protecting them. This is because all baby turtles grow inside eggs. The shells of turtle eggs are not hard, like those of a bird. Instead, they are softer and have the texture of thick plastic sheeting. Unlike fish or amphibians, turtles cannot lay their eggs in water, so they need to find dry land somewhere. Unlike birds, female turtles don’t stay with the eggs once they are laid, so their nesting spot has to be safe as well as dry.

From May to July, female turtles venture out of the water to look for good nest sites. They need to find areas that have sandy, well-drained soils that will keep the eggs from drowning. Nest sites must also stay moist enough to keep the eggs from drying out.

As soon as she selects a location, a female will dig a hole (about 4 inches deep) with her hind legs. Into this hole she will lay up to 20 eggs, which she will then cover with soil. Once this task is complete, she will have nothing more to do with her offspring.

The eggs hatch 10 to 11 weeks later between August and October. The babies from early nests will dig their way to the surface, while the babies from later nests may spend the winter underground and emerge in the spring. This is a neat trick considering they are able to survive the freezing temperatures of winter while only 4 inches from the surface!!

So, as the weather gets warmer in the next weeks and months, keep your eyes peeled for female turtles crossing the road while they look for places to lay their eggs. Their shells are tough and help to keep them safe, but they are not strong enough to protect them from cars. If you spot a turtle in the road, just tell your mom or your dad to slow down and swerve around her so she can go about her life and safely lay her eggs.

Bill Danielson has worked as a naturalist for 16 years. In that time, he has been a national park ranger, a wildlife biologist and a field researcher. He currently works as a high school chemistry and biology teacher. To contact Bill, or to learn more about his writing, visit www.speakingofnature.com

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