A Sculptured Turtle
Sep 30, 2019 02:12PM
At the end of October, there is a migration of sorts, a migration of turtles from fields, shrublands, and forests to the sandy banks of streams and rivers. These are wood turtles—Glyptemys insculpta—a cold-blooded species that is amphibian-like in its lifestyle, living mostly on land in summer and below water during winter. About the size of an oval luncheon plate, the wood turtle dines on insects, earthworms, berries, mushrooms, and succulent plants. Though they lack teeth, they have a hard, keratin-rich beak for grabbing, cutting, and tearing food.
Wood turtles are easily identified by the presence of projecting, or sculptured, ridges—thus the nickname sculptured turtle—on the upper shell or carapace. Unlike most turtles, the plates of the carapace are not shed regularly, and instead pile up in layers of increasingly larger size, with the small top plate representing the year of hatching. A wood turtle’s upper shell is dull brown with fine radiating lines of yellow. The neck, legs, and tail are heavily scaled and are boldly colored below in varying shades of yellow and orange, with the male bearing richer shades of orange in contrast to the female’s paler colors. The head is dark—nearly black in some individuals.
In mid-autumn, wood turtles congregate and mate. Females can store sperm for use in spring to fertilize a clutch of five to ten eggs. Turtle life then begins inside a white egg deposited within the sandy bank of a stream or river. June is nesting season, and it is not uncommon to see wood turtles searching the fine gravel on the Pine Creek rail trail for a suitable site. Eggs remain in the soil, unattended from June until late summer. When ready to emerge, the hatchlings slice open the leathery shell with a sharp egg tooth or caruncle. Then, in a frenzy, they dig upward and emerge onto the surface, somehow knowing where to head to reach the nearest water. About the size of a silver dollar and bearing a nondescript, smooth brown shell, the hatchlings, while well-camouflaged, are vulnerable to a variety of predators.
As the water chills, some turtles will anchor themselves among tangled tree roots below an overhanging stream bank. Others will burrow in the mucky bottom of a slow-moving stream. Protected from land-based predators, they will endure until warm weather returns.
If you are lucky enough to see a wood turtle while you’re out and about, be sure to give this animal the respect it deserves and let it be.