Throughout the state except the extreme north-central counties. History Current Status Excerpt from the Animal Guide Description Named after its discoverer, the Blanding's turtle is medium-sized. It can be easily identified by the bright yellow underside of its neck. The hinge of the Blanding's turtle's plastron is not functional until the turtle is 3 to 5 years old. Before this age its yellow throat markings are not apparent.
Males are larger than females, have longer tails, and their plastrons are concave for mating.
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 original range of the Blanding's turtle extended from southern Ontario and northwestern Pennsylvania in the East, through Ohio, Indiana, Michigan, Illinois, Wisconsin, and southern Minnesota and is found in Nebraska, Iowa, and extreme northeastern Missouri in the West. In Wisconsin, Blanding's turtles live throughout the state with the exception of the extreme north-central counties. They are most concentrated in the vast marshes along the Wisconsin River in Wood, Juneau, Adams, and Iowa counties. While Blanding's turtles live primarily in marshes and the shallow bays of lakes, they also can be found in shallow, slow-moving rivers, streams, and some northern bogs.