Leatherback Sea Turtle, Dermochelys coriacea, Family Dermochelyidae, Stock Photos, Pictures, Images

Other common names: Leatherback Turtle, Leatherback Seaturtle, Leatherback, Coffin-back, Trunk Turtle, Trunkback, Leathery Turtle, and in Latin America, Tinglado, Canal, Tortuga Laud, and Baula (Witherington, 2006)

The Leatherback Sea Turtle, Dermochelys coriacea, the largest species of sea turtle, is unique in many ways. It lacks a hard shell, has ridges along its back, has no claws and no scales, and it can elevate its body temperature, allowing it to function well in cold water.

The leatherback is a very large sea turtle, with exceptionally long flippers. Adult females generally weigh from 200 to 600 kg (440 to 1320 lbs) and have a shell length of from 145 to 170 cm (4 ft. 9 in. to 5 ft. 7 in.) (Witherington, 2006). The largest leatherback ever found, however, was a male that weighed 916 kg (2,019 lbs) and had a shell length of 2.56 meters (8 ft. 5 in.). Pacific leatherbacks tend to be smaller than Atlantic leatherbacks. The span of the leatherback’s flippers, from tip to tip, well exceeds the length of its shell.

Leatherback Sea Turtles are dark gray or black with small white and light gray blotches distributed uniformly over their bodies. The same blotchy pattern extends over their shell, head and flippers. They usually have a pinkish blotch on the top of their head. Only their underside is light in color.

Their body is streamlined, with large muscular shoulders and a teardrop-shaped shell. They have seven ridges on their shell that taper to a point at the rear. Unlike the shells of hard-shelled turtles, the leatherback’s shell is leathery, oily and cartilaginous, and strengthened by a network of numerous tiny bones. Leatherback sea turtles lack claws on their flippers. Their eyelids are thick and close to a vertical slit.

Leatherback sea turtles have a wider distribution than any other sea turtle. They nest in tropical waters, but feed in temperate waters as far north as Iceland and Norway, and as far south as New Zealand and Chile. When traveling from feeding grounds to nesting areas, they may migrate as far as 5,000 km (3,100 miles).

The leatherback sea turtle feeds mostly on coelenterates, particularly jellyfish. This diet of jellyfish is somewhat amazing, as jellyfish consist primarily of water and are poor in nutrients. Nevertheless, leatherbacks grow to a large size on this diet, as they feed continuously, eating twice their bodyweight in a single day. The jellyfish congregate in great numbers at a depth of 600 meters during the day, and the leatherback repeatedly dives to that depth to get them. They continue to feed when the jellyfish surface at dusk.

The leatherback has a unique w-shaped mouth that is well adapted for grasping and tearing jellyfish. They also have flexible spines in their mouth and throat that push food down toward their stomach while expelling sea water. Leatherbacks are also known to feed on crustaceans, squid, sea urchins, algae and seaweed.

Leatherback Sea Turtles have two amazing talents; they can dive to greater depths than any other sea turtle, and they can regulate their body temperature, allowing them to be active in cold waters. Scientists have measured leatherback sea turtle dives of over 1,000 meters (3,300 ft). The water at this depth is colder than 6 degrees centigrade (43 degrees F). Their oily skin and large, leathery shell help them conserve heat, so their body temperature stays higher than their surroundings. They also have a heat-exchange mechanism in their shoulder area, where cool blood from the flippers is warmed before it reaches the internal organs and shoulder muscles.

Female Leatherback Sea Turtle, Dermochelys coriacea, comes ashore to lay eggs with moon in background, Mexico, Pacific Ocean. Image #: 003385	Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Reptilia Order: Testudines Suborder: Cryptodera Superfamily: Chelonioidea Family: Dermochelyidae Genus Species: Dermochelys coriacea
	>>> More Leatherback Sea Turtle Pictures

The leatherback’s main nesting areas are northern South America, the Caribbean, tropical West Africa, the Andaman Islands, Indonesia, West Papua, and Pacific Mexico and Costa Rica. Some are also found in Florida. Females are known to return to the same nesting sites year after year. They favor extensive, sandy beaches with a steep slope to the ocean, allowing them to reach the nesting area quickly. They avoid rocks, which can damage their shell.

Nesting occurs in spring, when 65 to 85 eggs are laid four to nine times a season. Their nests tend to be deeper than the nests of other sea turtles, and they spend more time concealing their eggs with piled sand. Leatherbacks typically lay a number of yolkless eggs on top of their clutch of fertilized eggs. Explanations for this vary, but they may be a diversion for predators who eat their fill of them, leaving the fertilized eggs to hatch. Their function may also be to prevent sand from filling all the air spaces in the nest.

Hatchlings emerge in 55 to 70 days and weigh about 44 g (2 ounces). They are about 6. 25 cm long (2.5 inches) and they have tiny, beaded scales covering their bodies, which disappear as they mature. They are dark gray with white stripes along their carapace ridges and on their flippers.

Young leatherbacks live near the ocean surface, feeding opportunistically on matter that floats by. As they get older and can dive deeper, they spend their lives feeding in the open ocean. They grow more quickly than other sea turtles, doubling their weight every few months. Females reach sexual maturity after about 13 years.

The number of Leatherback Sea Turtles has been greatly reduced in recent years, particularly in the Pacific. Fewer and fewer reach nesting sites each year, and those that do often have their eggs poached. By the 1990’s, most nesting sites in India, Sri Lanka and Malaysia were eliminated by people harvesting eggs. Pacific Mexican nesting sites are now at 1% of their historical number. Another major threat in the Pacific is long-line fishing, which is responsible for thousands of leatherback deaths annually. Further, leatherbacks easily get tangled in fishing nets, causing them to drown. Finally, because floating plastic resembles squid, leatherbacks often choke on it and die.

The IUCN lists the leatherback sea turtle as Critically Endangered, and they will likely become extinct in the wild in the near future.

Sources:

Perrine, D. Sea Turtles of the World, Voyageur Press, 2003.

Ripple, J. Sea Turtles, Voyageur Press, 1996.

Witherington, B. Sea Turtles, Voyageur Press, 2006.

http://marinebio.org/species.asp?id=287