The Blanding’s turtle is a medium-sized, semi-aquatic freshwater turtle. It has a smooth, black shell with yellow spots. One of the most identifiable features is its bright yellow neck and throat.
What They Eat
The Blanding’s turtle is an omnivore, with a diet consisting of both meat and vegetation. Its diet includes crayfish, frogs, snails, fish, fish eggs, insects, tadpoles, earthworms, slugs, grubs, berries, seeds, leaves and carrion.
Where They Live
This North American species lives in wetlands, slow moving streams and nearby uplands. It ranges from portions of Canada into parts of the United States – as far south as Missouri, east to Maine, and west to South Dakota and Nebraska.
What They Do
Seasonally, the Blanding’s turtle moves between freshwater habitat and nearby terrestrial habitat. Blanding’s turtle breeding usually takes place at the start of spring. During late June or early July, the female turtle will leave the water in search of a safe nesting area. Under the cover of darkness, the female Blanding’s turtle will dig a hole in an area with good drainage and little vegetation. She will bury her eggs and then return to the water. Hatchlings leave the nest between mid-August and early October, and travel to nearby wetlands to overwinter. In winter months, the Blanding’s turtle remains buried in mud under the ice of ponds, marshes or slow moving rivers.
How They’re Doing
The International Union for the Conservation of Nature lists this turtle as “endangered.” The greatest threats to Blanding’s turtle survival are illegal collection, road mortality, predation (especially of eggs and young), and loss of habitat through wetland drainage, flooding, development and conversion to agriculture. In the state of Minnesota, the Blanding’s turtle is listed as a “threatened” species.
Where in the World
Wetlands and uplands
Body Length: 6–11 inches
Weight: 1.6–3.1 pounds
Number of eggs: 3–19 per clutch
Lifespan: 70–77 years
Where at the Zoo
- The Blanding’s turtle is named after Dr. William Blanding – an early naturalist from Philadelphia.
- Blanding’s turtles have a long lifespan and are not able to reproduce until they are 12-20 years old.
- The sex of turtle hatchlings is dependent on environmental temperatures. In general, female Blanding’s turtle hatchlings occur in nests with temperatures above 86°F and male hatchlings occur in nests with temperatures below 80°F. In nests with intermediate temperatures, a mix of male and female offspring will occur.
- Hatchling turtles rely on their sense of smell when moving from their nest to a wetland.
- Turtle egg and hatchling predators include shrews, skunks, opossums, raccoons and foxes.
- Unlike some aquatic turtles, Blanding’s turtles can swallow food without being in water.
- The Blanding’s turtle has specialized capillaries lining its mouths and cloaca that allows it to absorb oxygen from the water. These specialized blood vessels allow the turtle to stay underwater for long periods of time, as well as overwinter underwater.
- Blanding’s turtles have a hinge on the bottom part of their shell, or their plastron. The hinge on the Blanding’s turtle plastron is able to move once the turtle is two years old. By the time the turtle is five years old, it can move its hinge to fully close the bottom of its shell, thus protecting it from predators.
The International Union for the Conservation of Nature lists the Blanding’s turtle as “endangered.” This turtle is legally protected in many states where it occurs, including Minnesota. With a decreasing population, there are many threats to Blanding’s turtle survival. Habitat loss impacts this species as wetlands are drained or flooded, and upland areas are developed or converted for agriculture. The seasonal movements of this turtle put it at high risk of vehicle strikes as it slowly crosses roadways. Young turtles and eggs are preyed upon by a variety of predators including shrews, skunks, opossums, raccoons, foxes, domestic dogs and domestic cats.
There are a few things you can do to help Blanding’s turtles in Minnesota. When it’s safe to do so, assist turtles across roads in the direction they are moving. Don’t disturb turtle nests, and keep pets leashed so they can’t disturb nests, either. Help clean up litter, since trash can attract turtle predators such as raccoons. Leave shorelines natural and keep water free of pollution.
Things the Zoo’s Done/Doing
In 2018, the Minnesota Zoo received funding to begin partnering with other state agencies to better understand the threats facing Minnesota’s turtles. Using radio telemetry and GPS transmitters, we are tracking wood turtles and Blanding’s turtles to learn about habitat use and nesting locations. This data will provide information on turtle needs and help to inform best management strategies. We are also investigating road mortality impacts on turtles by surveying sites around the greater Twin Cities metro, and testing the effectiveness of mitigation strategies such as small animal exclusion fencing.