Snapping turtle
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 Common Snapping Turtle
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Snapping turtles (or snappers) are large, New World freshwater turtles of the family Chelydridae. The species range from southeastern Canada, west to the Rocky Mountains and south through Mexico to Ecuador.
Snapping turtles are noted for their pugnacious disposition and powerful beak-like jaws which may contain serrations on the margins that resemble teeth. They have a muscular build with ridged shells. The carapce length of modern snapping turtles ranges from 50 cm long in Chelydra to some 80 cm long in the Alligator Snapping Turtle (Macroclemys temminckii). The latter species is one of the largest freshwater turtles in the world, weighing up to 200 kilograms. The Common Snapping Turtle (C. serpentina) and its subspecies are much smaller, weighing up to 75 kilograms. Common snapping turtles kept as pets can become quite corpulent and difficult to move without their cooperation and require frequent cleaning of their water tanks to remain content and healthy. In some areas, they are hunted heavily for their meat. They may live for 120 years or more.
Snapping turtles have long spiked tails and long, flexible necks, which can reach two thirds the length of their shells, making handling dangerous. They cannot fully retract their head and appendages, relying on fierce displays when aggravated. Their snapping jaws and sharp claws are capable of inflicting serious injury.
Strangely enough, the Common Snapping Turtle, when raised in captivity from a hatchling, can sometimes become extremely docile and devoted to its owner. It may show signs of intelligence in recognizing individual people and will seek out those whose company it prefers. Some can be taught to obey simple commands, but this can be a long process, as Snapping Turtles display the stubborn nature that is a defining characteristic of all turtle species.
These turtles spend most of their time in ponds, shallow lakes and streams. Snapping Turtles commonly bask by floating on the surface with only their carapace exposed. The belief that they never leave water to bask derives from the fact that they are often very secretive about doing so, though in the northern parts of their range Common Snapping Turtles readily bask on fallen logs in early spring. Snapping Turtles also travel overland to reach new habitat. Pollution, habitat destruction, food scarcity, overcrowding and other factors will drive snappers to travel across land. It is common to find Common Snapping Turtles traveling far from the nearest water source. Alligator Snapping Turtles are much more aquatic and typically only females leave the water willingly, in order to lay their spherical eggs in June and July. Some may inhabit brackish environments, such as estuaries. All snapping turtles are omnivores and are important scavengers but they also actively hunt fish, frogs, birds and small mammals. The alligator snapper has a flesh-red, worm-like tongue, which it uses to lure fish into its mouth.
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[edit] Fossil Record of Chelydridae
The family Chelydridae has a long fossil history with extinct species reported from North America, Asia and Europe, far outside its current range. The earliest described chelydrid is Emarginachelys cretacea, known from well-preserved material from the Maestrichtian (Late Cretaceous) of Montana. Another well-know fossil chelydrid is the Late Paleocene Protochelydra zangerli from North Dakota. The carapace of Protochelydra is higher domed than that of Recent Chelydra, a trait that has been conjectured to be associated with the sympatric existence of large chelonivorous crocodilians. Example of a well-known Eurasian chelydrids are members of the genus Chelyropsis, several species of which existed from the Oligocene to Pliocene. The genera Macroclemys and Chelydra, each with one living species, are traditionally accepted as the only extant members of the family Chelydridae, although the monotypic Asian genus Platysternon has sometimes been included in the group. The genus Macroclemys is exclusively North American and is generally considered to contain three valid species, the extant M. temminckii and the extinct M. schmidti and M. auffenbergi, described from the early middle Miocene of Nebraska and the middle Pliocene of Florida, respectively. The genus Chelydra also is exclusively North American. The earliest occurrence of the genus Chelydra is from the late Barstovian (middle Miocene) of Cherry County, Nebraska. This assignment is based on a single partial right hypoplastron that is described as being markedly more massive and rugose than C. serpentina. No species assignment was made for this specimen. Published reports of Chelydra from the Pliocene involve very scant material. A large, undescribed fossil member of the genus Chelydra is known from upper Pliocene localities of North Florida. Specimens of this new species are by far the largest Chelydra ever discovered, reaching a carapace length of over 50 inches (127 centimeters). Abundant records of Chelydra from the Pleistocene have been published.
[edit] Reproduction
Snapping turtles mate from April through November, with their peak laying season in June and July. The female snapper can hold sperm for several seasons, utilizing it as necessary. Females travel over land to find sandy soil in which to lay their eggs, often some distance from the water. After digging a hole the female deposits typically 25 to 50 eggs, guiding them into the nest with her hind feet, and covers them with sand for incubation and protection. Incubation time is temperature-dependent, ranging from 9 to 18 weeks. In cooler climates, the hatchlings overwinter in the nest.
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[edit] Handling snapping turtles
It is a common misconception that a snapping turtle may be safely picked up by its tail, with no harm to the animal; in fact, this has a high chance of injuring the turtle. A handler must also be wary of injury to himself. Snapping turtles are aptly named, as they can snap with amazing speed and power; a full-grown snapper can easily nip off a finger. The safest method, of course, is to avoid handling a snapper at all. Lifting a snapper with a shovel is a safe technique that protects both the handler and the turtle. Lifting the turtle just off the ground to move it is advised, as otherwise they can easily squirm and fall off the shovel.
Lifting the turtle with the hands is more difficult. Some snappers can stretch their necks halfway back across the carapace. Manual lifting is best done by sliding fingers behind the turtle's hind legs, with the tail between the hands and gripping the turtle between the fingers and thumbs. The handler then proceeds to lift the turtle only just off the ground. The turtle will probably squirm and try to dislodge the handler's hands with its hind legs. Snappers are often slimy and wet, and they are good at causing handlers to lose their grip, so it is best to have the turtle already almost on the ground. The turtle may be covered with a smelly slime and may also defecate or urinate on a handler, who can usually expect his hands to be smelly after carrying a turtle.
[edit] Role in political history
The snapping turtle, known commonly and in folklore as the "Ograbme", was the central feature of a famous American political cartoon published in 1808, in protest at the Jeffersonian Embargo Act of 1807. The cartoon depicted a snapping turtle, fervently holding on, with its jaws, to an American trader, who was attempting to carry a barrel of goods onto a British ship. The trader was seen whimsically uttering the words "Oh! this cursed Ograbme", which was Embargo spelled backwards. This piece is commonly considered to be a pioneering work, within the genre of the modern political cartoon.
[edit] Classification
Family Chelydridae
- Genus Acherontemys (extinct)
- Genus Chelydrops (extinct)
- Genus Chelydropsis (extinct)
- Genus Emarginachelys (extinct)
- Genus Macrocephalochelys (extinct)
- Genus Planiplastron (extinct)
- Subfamily Chelydrinae
- Genus Protochelydra (extinct)
- Genus Macrochelys
- Genus Chelydra
[edit] Trivia
[edit] See also
[edit] Gallery
 Common Snapping Turtle investigating a board |
 Snap! |
 Common Snapping Turtle |
 Snapper and Canada Goose |
[edit] External links
- View the Ograbme Cartoon (Shown in Question #5)
- The Snapping Turtle Page - www.chelydra.org
- Snapping Turtle Resources
