The Great Outdoors | July 1, 2018
By Jackie Scharfenberg, Naturalist, Wisconsin Department of Natural Resources
Oh, how I despise traveling on land! It makes me extremely cantankerous! I hiss, lunge, and snap with my sharp “beak” at anything that gets too close. You may even detect a foul smell coming from near my rear legs. Snapping turtles (Chelydra serpentine), like me, belong in the water of lakes, ponds, marshes, and slow-moving rivers!
Now that my carapace (top shell) has reached eight inches and I’m over five years old, it’s time for me to leave the water to find a sandy spot. I’ll lay 20-40 or sometimes even 100 white ping-pong shaped eggs. Using my strong back legs, I dig a four-to-seven-inch-deep hole. Afterward, I deposit my eggs, cover them, and finally head back to the safety of the water. This all takes place from late May into July.
Temperature determines much of a snapper’s life. If my eggs experience warmer temperatures during a set five-day window, the hatchlings will become female. Cooler temperatures will produce males, and in between weather will yield a mixed clutch. Hatching occurs anywhere from two to three months later, depending upon the temperature. If my eggs hatch late, the young may stay in the nest until spring.
As Wisconsin’s largest and heaviest turtles, our adults encounter very few predators. Our predators include humans, skunks, racoons, crows, and foxes dig up our nests to eat our eggs. The poor little hatchlings must escape the jaws of those egg-eaters, as well as, bullfrogs, largemouth bass, great blue herons, larger turtles, and water snakes. If our hatchlings make it through year one, they may live 30 to 45 plus years.
Habitat and Hibernation
Water temperature gives us clues regarding when to hibernate in the mud and when to wake up in spring. We can tolerate colder water than most turtles, so you may see a few crazies walking under the ice. Being exothermic, the temperature of the environment determines our body temperature. To warm ourselves, we bask on logs sticking out from the water, or often by floating with just our carapace sticking out of the water.
We enjoy a solitary life. During the warm months, we bury into the mud exposing only our eyes and our nostrils, which are located on the tip of our snorkel-like nose, above the water. We hunt mostly at night. We use a small worm-like growth on the tip our tongue to lure in fish and other prey. Another approach we use involves ambushing any passing critter we can fit into our large mouths. We also eat a lot of aquatic plants, making us true omnivores.
We Are Snappers
Warning! Out of the water, we become quite aggressive since we cannot pull into our shells. Our plastrons (lower shell) cover only a small area between our legs. With our highly mobile neck and head, we lash out with our big mouths wide open for defense. Our strong jaws and powerful beaks can cut off a finger! Back in the water, we become quite docile preferring to flee and hide in the bottom sediment or weeds. Let’s make a deal. If you give us our space, we won’t hurt you!