Pictures of the Month!
| Home |
| Reptiles of Maryland |
| Amphibians of Maryland |
| Research at Towson |
| Photo Gallery |
| Herpetology Links |
| References |
This site was created by students in the herpetology class at Towson University. Site last updated: 05/21/07.
Acknowledgements: Herb Harris - Range Maps; Mark Tegges - Photography; Dan Lapascha & Gigi Forester - TU Herpetology Logo
Snapping turtle
(Chelydra serpentina)
Description
The snapping turtle gets its name from its powerful jaws, the upper of which is strongly hooked, and its massive head. Its prehistoric appearance makes it an easy local species to identify. It is a large species ranging in size from 20-47 cm in length. The carapace is tan to dark brown, relatively flat, has noticeable keels along the dorsal midline and serrated posterior marginal scutes. The plastron is greatly reduced, cross-shaped and yellow to tan in color. Snapping turtles cannot tuck their head into their shells as most turtles can; this is in part due to their reduced plastron. The tail can be long and always has saw-toothed keels. The skin is usually gray to dark brown. The neck is very thick and often long enough to extend three-quarters of the length of the carapace. They can exceed 40 lbs in weight. Hatchling snapping turtles have 3 distinct rows of dorsal keels that tend to flatten with age and tails that are at least as long as the carapace.
Habitat
Although they can be found in freshwater or brackish water, snapping turtles prefer still waters typical of pond and lake habitats with sandy or silty bottoms and plentiful vegetation. During the winter months these turtles burrow into the muddy substrate and hey typically emerge in late spring when the pond water warms. Due to their highly vascularized shell, snapping turtles do not have a great need for basking. They do, however, float along the upper surface of the water to gain some heat from the sun’s rays. Snapping turtles are carnivorous and as such will eat fish, frogs, small ducks and even other turtles. Research has shown this species to be highly tolerant of various aquatic pollutants; therefore, snapping turtles are commonly found in otherwise undesirable habitats.
Breeding
Snapping turtles mate from March to November under water. Males are aggressive and may even force copulation with females. The male will hold onto the female’s carapace with all 4 feet after which a series of violent muscular contractions of the legs, neck and tail occur. Additionally, the male may bite at the female’s head and neck during copulation. The female can store sperm for several years. Although peak egg laying season is in June, females can be seen nesting throughout the late spring and early summer. Females seem to test the substrate by digging several nest cavities before choosing one in which to deposit the eggs and will travel some distance from the water for a preferred nesting site. Females generally lay 1 clutch ranging from 20 to 75 eggs resembling ping pong balls. Based on temperature, the hatchling turtles will emerge from the nest in 9 – 18 weeks and are the size of a half dollar. Some hatchlings may overwinter in the nest before emerging.
Distribution in Maryland
Range map adapted from Harris, 1975.
Links
http://www.tigr.org/reptiles/families/Chelydridae.html
http://animaldiversity.ummz.umich.edu/site/accounts/information/Chelydra_serpentina.html