Common Snapping Turtle
Pictured Above: Common Snapping Turtles are cantankerous (top left). A Common Snapping Turtle's plastron is reduced compared to other turtles (top right).
Description: Common Snapping Turtles are one of the largest turtles found in the La Crosse area, reaching adult carapace lengths of 15+ inches. Common Snapping Turtles are usually uniformly brown, olive, or black in color. In some cases, their undersides are are tan or beige and the plastron is always reduced compared to other turtles (see above pictures). The carapace of these turtles has three rows of keeled scutes that may be pointed, and a serrated back edge (pictured above). A Common Snapping Turtle's tail extends out from the back of its carapace and is dorsally lined with "teeth-like" projections (pictured above). Common Snapping Turtles are members of the family Chelydridae.
Habitat/Ecology: These turtles are commonly found in almost any type of water body, however, they seem to prefer habitats with muddy bottoms and ample vegetation. They are known to bask in the early spring, but it is uncommon for them leave the water. I have rarely witnessed these turtles far from water unless in the process of nest-building. Common Snapping Turtles will consume a variety of food items including; fish, frogs, other turtles, snakes, small mammals, and various vegetation. Nest-building generally takes place during the month of June, and females lay spherical eggs (not elliptical eggs like map turtles). Hatchlings will emerge from late July through late August, depending on when the nests were originally built. Common Snapping Turtles generally over-winter under water in areas close to spring-heads. This cold spring-fed water is higher in oxygen and can sustain them throughout the winter hibernation period.
Remarks: Snapping Turtles are notoriously ill-tempered and will strike viscously and repeatedly if threatened. They will also claw and release a foul smelling odor. Due to their extremely aggressive nature, these turtles should never be handled. If they are left alone, they pose no threat. As a child, I frequently encountered them near the Yahara River, which is by no means a "clean" body of water, in Stoughton, WI (Dane Co.). This leads me to believe that these turtles can withstand a certain degree of human-induced habitat degradation.
Common Snapping Turtles are frequently trapped or "hooked" by people who eat their flesh. It should be noted, however, that there are restrictions on the size and number of these turtles that an individual can harvest in Wisconsin. Therefore, anyone who wishes to trap them must contact the Wisconsin Department of Natural Resources for specifics.
It is interesting to note that Alligator Snapping Turtles (Macroclemmys temminckii) were once said to be found in Wisconsin near the Mississippi River and Wisconsin River confluence (Grant Co.). Now, however, this species is rarely found as far north as southern Illinois.
I have found Snapping Turtles in several locations throughout La Crosse (including Myrick Park and Green Island) and I believe them to be relatively common here. Within the state, they can also be found along the Wisconsin and Rock Rivers