Blanding's Turtles are medium-sized water turtles. They can be easily identified by the bright yellow undersides of their necks. The head, tail, and limbs are bluish-black. The upper shell (carapace) is usually black speckled with yellow, while the hinged lower shell (plastron) is yellow speckled with black or brown.
The carapace of a Blanding’s Turtle measures 5-8 inches (12-20 cm) across.
- The hinged plastron allows the turtle to close the front half of the shell tightly, protecting the soft flesh of its head, neck, and legs from predators.
- The flat-topped shell and slightly webbed feet of the Blanding's Turtle help it to move efficiently through the water.
In the wild, Blanding's Turtles will eat a variety of food, including crustaceans, snails, insects, berries, and grasses. At Cosley Zoo, the Blanding's Turtles are fed mixed greens, crickets, earthworms, fish, young mice, and a processed turtle food.
Mating usually occurs in the water during early spring. The turtles will travel up to 1 1/2 miles from water onto land to nest. They usually return to the same nesting site each year. Once they deposit the eggs in the ground, the mothers return to the water, and the sun's warmth incubates the clutch of 3 to 17 eggs. In 65 to 90 days, the eggs hatch. Hatchlings are about 1 1/4 inches long and range from dark gray to green in color. From the time they hatch, the young turtles are on their own. Like most turtles, Blanding's Turtles do not exhibit parental care towards their young.
Shelter and Space Needs
The Blanding's Turtle is semi-aquatic. It prefers open, grassy marshes containing shallow water, but it will, on occasion, move to ground adjacent to water to forage or bask in the sun.
Blanding's Turtles have the potential to live 75-80 years. However, their juvenile mortality rate is extremely high due to predation on eggs and young turtles and increasing lack of suitable habitat. Only a small percentage of Blanding's Turtles in Illinois live to sexual maturity, which occurs at 15-20 years of age.
Relationship with Man
Turtles are important to the health of their ecosystems because they eat a wide variety of food, including both plant and animal material. Turtles, along with other reptiles, also serve as "environmental indicators." They are particularly sensitive to changes in the quality of their surroundings and therefore their health reflects the health of their environment. In Illinois, the Blanding's Turtle is an endangered species due to illegal collection for the pet trade and habitat destruction. The DuPage County Forest Preserve District, Peggy Notebaert Nature Museum, St. Charles Park District, Brookfield Zoo, and Cosley Zoo are working together to implement a recovery program to increase the wild population of these animals.
- In many types of turtles, including Blanding's, the temperature at which the eggs incubate determines the sex of the hatchlings. More females are produced at higher incubation temperatures and more males are produced at lower incubation temperatures.
- Turtles do not have teeth! Instead, they have a beak that is used to tear food into pieces.
- A turtle's shell is made up of about 60 bones. If you look closely at a turtle's upper shell, you can see a raised line running from head to tail. This line is the turtle's backbone.
- Like many turtles in this area, the Blanding's Turtle survives the winter by burying itself in the mud or silt at the bottom of a pond and entering a state of dormancy that is somewhat like hibernation.