by Patrick Harmon
Spring finally makes its debut with flowers blooming and trees growing their leaves, the landscape transforms into an emerald wonderland as plants come back to life. With the return of such greenery we also see the re-emergence of countless mammals, amphibi-ans, insects, and reptiles. One of these reptiles is the incredibly rare wood turtle.
The scientific name of the wood turtle, Glyptemys insculpta, comes from the patterns of the scutes on its shell which appear similar to tree bark. Their carapaces are mostly dark gray-brown while their plastrons are yellowish with black splotches at the outer end of each scute. Their head and limbs are mostly gray with yellow or orange accents, making them quite colorful and similar to many other North American pond turtles. Wood turtles are a long-lived species capable of achieving a lifespan of over 50 years in the wild. This species is omnivorous meaning it eats both plant and animal matter and they are not very picky. They will eat things like fruit, algae, insects, tadpoles, moss, leaves, and even carrion.
During the spring these turtles favor slow-moving woodland streams with ample vegetation lining the banks. Although they are almost always within a few hundred meters of water, wood turtles can travel far distances in search of suitable habitat or mates. During the summer wood turtles may move to more open areas like forests, meadows, and bogs. If it gets too hot during the peak of summer, wood turtles can estivate.
This is when an animal enters a state similar to hibernation in order to escape hot or dry conditions in their environment. Once the heat of the summer dies down and fall begins, wood turtles will prepare to overwinter in the muddy banks of streams. This usually occurs from October until March. Once they reawaken, males will begin to seek out mates.
Males form a social hierarchy that is usually dependent on age, size, and their levels of aggression. The dominant males tend to be the largest, oldest, and most aggressive individuals and thus have the highest reproductive success. When a male has found a female, the two will enter a courtship “dance” followed by the male chasing and nipping at the female’s limbs. After mating, the male will leave in search of more females.
When it comes to nesting, female wood turtles are very particular about where they choose to lay their eggs. Factors like canopy cover, vegetation, and substrate type can all impact the chances of nesting success. When she chooses an appropriate area she will dig a shallow cavity around 2-5 inches deep and lay a clutch of 3 to 18 eggs. Unfortunately, hatchlings have a very low survival rate and most nesting attempts result in failure. Those that are lucky enough to survive the 47-69 day incubation period will hatch sometime between late August and September. Most of these surviving young often do not make it to adulthood however. Eggs and hatchlings are readily preyed upon by animals like raccoons, foxes, snakes, and birds. Even adults face many dangers, especially when traveling long distances. Wood turtles that have to cross roadways or farmlands can be injured or killed by vehicles and farming equipment. These turtles have also been taken from the wild by commercial poachers who wish to sell them illegally as pets or food. Their survival is also impeded by their life history, as wood turtles are not sexually mature until around 14-20 years of age. These factors put them at risk of extinction, making them among the rarest freshwater turtles in North America.
Here at the reservation, we use radio transmitters to track the movements of individual turtles throughout the park and monitor their health. You too can help turtles by watching out for them as they cross roads, picking up trash, and leaving them in their habitat. Just by following steps like these, we can all do our part to make sure that this incredible species of turtle has a fighting chance