Leatherback sea turtles, named for their leathery skin, are notable for their size and power. They are the largest sea turtle and one of the largest reptiles, weighing as much as 900 kg. They can out-swim a shark and dive as deep as a whale, reaching down to 1230 metres. They produce the largest hatchlings and migrate the furthest distance. They are found in all the world’s oceans from the Arctic to the tropics and down to the Southern Ocean.

Scientific Name
Dermochelys coriacea

Conservation status
Leatherback turtles are classified as Critically Endangered by the International Union for Conservation of Nature (IUCN)

Description
Leatherbacks are recognised by the 5 ridges running along the length of the carapace (top of shell). Their carapace is black with light spots and they have pale pink spots on top of the head and a very pointed posterior. They have a soft leathery shell rather than the hard shell usual with sea turtles. This may be an adaption to withstand the pressure found at the extreme depths to which they dive. Adult carapace length averages 1.6 metre.

Hatchlings are black with white markings along carapace ridges and on the plastron (under part of shell).

Distribution
Leatherbacks have the largest range of any sea turtle and are found in all oceans of the world. They can be found in tropical and temperate waters and even on the edge of arctic waters. They have been seen off the coast of Canada, Great Britain, Alaska, Argentina, New Zealand and South Africa.

Habitat
Leatherback Turtles are oceanic and are found in all the oceans of the world. They migrate great distances between cooler feeding grounds rich in jellyfish and tropical nesting beaches.

Lifecycle
Once a leatherback hatching enters the water it swims continuously for up to 6 days and nights. Also taken by ocean currents, the hatchlings tend to congregate in the open water. Little is known about these early years and they are still considered to be the ‘lost years’. Leatherbacks remain in pelagic waters their entire life apart from when nesting.

Diet
Leatherbacks are carnivorous and feed mainly on jellyfish. They also eat tunicates, hydroids, amphipods and crabs. Juveniles must eat substantial quantities of jellyfish every day to support their rapid growth.

Nesting
Females nest every 2 to 4 years and mating takes place all along the migration route as well as off nesting beaches. Some leatherbacks have shown less dedication to their natal beach than other turtle species due to changing sand structures that causes them to choose beaches with the most suitable sand composition. The French Guiana coast in South America has the largest nesting colony with other major nesting sites in Gabon West Africa and Costa Rica. On beaches undisturbed by predators hatching success is low at 50% for reasons as yet unknown.