Turtles of Wisconsin
Biology and Behavior
There are 260 species of turtle worldwide.
This is one of them, the false map turtle.
Turtles are believed to have existed on earth longer than any other group of reptiles. Fossil records suggest that they were present as long as 200 million years ago and that they haven't changed much since that time. They are also believed to be one of the longest living creatures. Some species live past 100 years of age. There have been individual turtles that made it to 200 years-old. How can we know that? Turtle havesters report that some alligator snapping turtles harvested in recent years have had arrowheads and musket balls lodged in their shells. How long ago did we use muskets in this country?
Turtles belong to the animal kingdom, phylum Chordata (animals with backbones). They are reptiles covered by scales or horny plantes. Turtles are exothermic or cold-blooded, and unlike humans, they get their body heat from outside sources like the sun. There are approximately 260 species worldwide, 55 native to the United States, and 11 species in Wisconsin. Any idea which turtle species in Wisconsin is the most abundant? It's the painted turtle.
Wisconsin's turtles represent four of the turtle families. There are the mud and musk turtles (one species); the snapping turtles (one species); box and water turtles (seven species); and the softshell turtles (two species). One of Wisconsin's turtles--the ornate box turtle is Wisconsin's only terrestrial (totally land-dwelling) turtle.
Where Do They Go in Winter? Ten of Wisconsin's 11 turtle species spend the winter under water. Some bury themselves under the bottom while others lie on the bottom and remain motionless. Recent studies show that many turtles don't actually hibernate. The remain semi-active, moving about during the winter. Because winter takes a toll on body reserves, many species begin to emerge as soon as the ice starts to melt around lakes, ponds, and streambanks. Turtles will come to bask on sunny days in early spring when air temperatures near 50 degrees Fahrenheit. Of course, the ice has to have melted enough so that they can get to the shoreline.
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