Scientific Name: Dermochelys coriacea Fijian Name: ‘tutuwalu’
Species Description
The ‘tutuwalu’ or leatherback is the only sea turtle that lacks a hard bony shell. Rather it consists of a leathery, oil saturated connective tissue overlaying loosely interlocking dermal bones. The leatherback is the largest turtle and the largest living reptile in the world. Mature males and females can be as long as six and a half feet (2m) and weigh almost 2000lbs or 900kg. The front flippers lack claws and scales and are proportionally longer than in other sea turtles; back flippers are paddle shaped. The ridged carapace and large flippers are characteristics that make the leatherback uniquely equipped for long distance foraging migrations.
Female leatherbacks lay clutches of approximately 100 eggs on sandy tropical beaches. Females nest several times during a nesting season, typically at 8 to 12 day intervals. After 60 to 65 days leatherback hatchlings with white striping along the ridges of their backs and on the margins of the flippers emerge from the nest. Leatherback hatchlings are approximately 50 to 77 cm (2 to3 inches) in length, with fore flippers as long as their bodies, and weigh approximately 40 to 50 grams.
Leatherbacks lack the crushing chewing plates characteristic of sea turtles that feed on hard-bodied prey. Instead, they have pointed tooth-like cusps and sharp edged jaws that are perfectly adapted for a diet of soft-bodied pelagic (open ocean) prey, such as jellyfish and salps. A leatherback’s mouth and throat also have backward-pointing spines that help retain such gelatinous prey.
Habitat
Leatherbacks are commonly known as pelagic animals, but also forage in coastal waters. In fact, leatherbacks are the most migratory and wide ranging of sea turtle species. Thermoregulatory adaptations such as a counter current heat exchange system, high oil content, and large body size allow them to maintain a core body temperature higher than that of the surrounding water, thereby allowing them to tolerate colder water temperatures. Leatherbacks mate in the waters adjacent to nesting beaches and along migratory corridors. After nesting, female leatherbacks migrate from tropical waters to more temperate latitudes which support high densities of jellyfish prey in the summer.
Distribution
Leatherback turtle nesting grounds are located around the world with the largest remaining nesting assemblages found on the coasts of northern South America and west Africa. The global nesting population is estimated to be around 34,000 females. Little is known on the nesting population for leatherbacks in Fiji. However there have been sightings in Savusavu, Qoma, Yaro passage, Vatulele and Tailevu.
The distribution and developmental habitats of juvenile leatherbacks are poorly understood.
Population Trends
The Pacific Ocean leatherback population is generally smaller in size than that in the Atlantic Ocean. Because adult female leatherbacks frequently nest on different beaches, nesting population estimates and trends are especially difficult to monitor. In the Pacific, the World Conservation Union (IUCN) notes that most leatherback nesting populations have declined more than 80%. In other areas of the leatherback’s range, observed declines in nesting populations are not as severe and some population trends are increasing or stable.
Threats
Like the other marine turtles leatherback turtles face threats on both nesting beaches and in the marine environment. The greatest causes of decline and the continuing primary threats to leatherbacks worldwide are long term harvest and incidental capture in fishing gear. Harvest of eggs and adults occurs on nesting beaches while juveniles and adults are harvested on feeding grounds. Incidental capture primarily occurs in gillnets, but also in trawls, traps and pots, long-lines and dredges. Together these threats are serious ongoing sources of mortality that adversely affect the species’ recovery. For more information, please visit our threats to marine turtle’s page. Conservation effort
Being migratory and highly pelagic, leatherbacks face the same threat that the other marine turtles face. A coordinated conservation initiative between States is needed to ensure that sufficient effort is given towards the work of conserving leatherbacks.
Regulatory Overview
Leatherback turtles are listed in Appendix I of the Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES), which means that international trade in this specie is prohibited.
