The snapping turtle adult is about eight to 12 inches long and weighs 10 to 35 pounds. It has an enormous head, thick legs and a long tail that is saw-toothed on the upper side. The carapace (top of shell) has three weak keels (ridges) that often have algae growing on them. The plastron (bottom of shell) is small. This turtle is unable to withdraw completely into its shell. The young turtle is black with some gray or olive spots. The adult is olive, gray or black.
The snapping turtle may be found statewide in Illinois. It lives in any permanent body of water. Although aquatic, this species is often encountered on land as it migrates from one body of water to another. The animal is very aggressive out of water and will attempt to bite. In water, it is calmer. It spends much of its time on the bottom of a water body waiting for prey items to come close. It buries itself in the mud in winter, often near other snapping turtles. The mating season lasts from April through November, although most mating occurs in late spring. The female digs a nest in soil in mid-May or early June and deposits 20 to 40 eggs. Eggs hatch in September and October. The snapping turtle eats almost anything it can catch and swallow, including insects, crayﬁsh, fishes, birds, amphibians, reptiles and mammals. It also does some scavenging and eats vegetation.