Like all turtles, snapping turtles have a shell that covers their back, also called a carapace. In snapping turtles the carapace is normally between 8 and 18 1/2 inches long. The shell color ranges from dark brown to tan and can even be black. As a snapping turtle grows, the shell often becomes covered with mud and algae. The tail has sharp ridges running along its length, and is nearly as long as the shell. Their necks, legs, and tails have a yellowish color and the head is dark. A snapping turtle's mouth is shaped like a strong, bony beak with no teeth. Their skin is rough with characteristic bumps, called tubercles, on their necks and legs. The feet are webbed and have strong claws.
Turtles have another hard plate that covers the stomach; this is called a plastron. A snapping turtle's plastron is small and leaves much of their body exposed. This means that they cannot pull their head and legs into their shell for protection against predators, as most other turtles can. Snapping turtles make up for this lack of body armor with an aggressive temperament.
Snapping turtles are native to the Nearctic region. Their range stretches from Southern Alberta and east to Nova Scotia in Canada and extends south to the Gulf of Mexico and into central Texas.
Snapping turtles live only in fresh or brackish water. They prefer water with muddy bottoms and lots of vegetation so that they can hide more easily. Snapping turtles spend almost all their time in water, but do go on land to lay their eggs in sandy soil.
In the wild snapping turtles are estimated to live up to 30 years. Snapping turtles are most vulnerable as hatchlings. Once they reach a certain size there are few natural predators of snapping turtles, though they are often hit by cars when searching for new ponds or nesting sites. In captivity they can live up to 47 years.
Snapping turtles are solitary, which means that they live alone. Even though many turtles may be found in a small area, their social interactions are limited to aggression between individuals, usually males. The number of turtles found living in the same area depends on the amount of available food. Snapping turtles can be very vicious when removed from the water, but they become docile when placed back into the water. Snapping turtles like to bury themselves in mud with only their nostrils and eyes exposed. This burying is used to surprize prey. Snapping turtles have a small growth on the end of their tongues that looks like a wriggling worm. To capture fish, the snapping turtle opens its mouth to make the "worm" visible. When a fish comes to the worm, the snapping turtle grabs it with its strong jaws.
Snapping turtles communicate to mates with leg movements while the turtles face each other. Snapping turtles also use their sense of smell, vision, and touch to detect prey. They may sense vibrations in the water.
Snapping turtles will eat nearly anything that they can get their jaws around. They feed on dead animals, insects, fish, birds, small mammals, amphibians, and a surprisingly large amount of aquatic plants. Snapping turtles kill other turtles by biting off their heads. This behavior might be to protect their territory from other turtles or it may be a very inefficient feeding behavior.
The eggs and hatchlings of snapping turtles may be eaten by other large turtles, great blue herons, crows, raccoons, skunks, foxes, bullfrogs, water snakes, and large predatory fish, such as largemouth bass. However, once snapping turtles become larger, there are few animals that prey on them. Snapping turtles are highly aggressive and will fight back ferociously.
Snapping turtles eat the young of some fish that humans like to catch, but snapping turtles do not eat enough to have much of an impact on the fish populations. Snapping turtles are known to kill young and adult ducks and geese, but once again the effects are small.
Snapping turtles are used by many people in turtle stews and soups. Snapping turtle shells were used in many ceremonies among Native Americans. The shells were dried and mounted on handles with corn kernels inside for use as rattles.
Snapping turtle populations are not close to extinction or even threatened. The destruction of the ponds they live in could pose a danger to snapping turtle populations at a later time. Some individuals are killed for food, which does impact the population, but in a very minor way.
Adam T. Bosch (author), University of Michigan-Ann Arbor.
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