Underwater giant on the brink
Background
Although Atlantic populations are rather more stable, models predict that they, too, will decline due to the large numbers of adults being killed accidentally by fishing fleets. In the Atlantic, the fact that they are widely distributed during the migration process and that they do not dive very deep increase the risk of interaction of leatherback turtles with longline fisheries.
WWF is working to conserve leatherback turtles and their habitats in Central and South America, and the western Pacific through concerted pan-Pacific and trans-Atlantic approaches that aim to protect critical nesting beaches and migratory pathways. This is being achieved by:
- protecting nesting beaches and nearshore habitats by establishing and strengthening sanctuaries and wildlife refuges;
- raising awareness so that local communities will protect turtles and their nests;
- promoting regional agreements to conserve marine turtles;
- reducing longline bycatch through promoting and facilitating gear modification, using new migration and genetics information to develop and trial management measures and ensuring that any traditional take is sustainable.
The leatherback turtle is the largest marine turtle and one of the largest living reptiles. Leatherbacks are one of the most migratory of all marine turtle species, making both trans-Atlantic and trans-Pacific crossings. They are easily distinguished by their carapace, which is leathery, not hard as in other turtles, and by their long front flippers.
Leatherbacks have a unique system of blood supply to their bones and cartilage. This enables their body temperature to stay several degrees above the water temperature and allows them to tolerate cold water, rather like a mammal. They can dive to depths of up to 1,200m, much deeper than any other marine turtle.
Recent DNA analysis confirms that Atlantic and Pacific populations are genetically distinct lineages of a single species. In turn, nesting Pacific leatherback populations are separated into two genetically distinct populations (eastern and western populations).
A leatherback was recorded to have descended to a maximum depth of 1,230 metres, which represents the deepest dive ever recorded for a reptile.
Range States
Albania, Angola, Antigua and Barbuda, Aruba, Australia, Bahamas, Barbados, Brazil, Cayman Islands, China, Colombia, The Democratic Republic of Congo, Costa Rica, Cuba, Cote d'Ivoire, Dominica, Dominican Republic, Ecuador, El Salvador, Eritrea, Fiji, Fench Guiana, Ghana, Grenada, Guadeloupe, Guatemala, Guyana, Haiti, Honduras, India, Indonesia, Jamaica, Liberia, Malaysia, Martinique, Mexico, Montserrat, Mozambique, Myanmar, Netherlands Antilles, Nicaragua, Panama, Papua New Guinea, Peru, Puerto Rico, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Senegal, Solomon Islands, South Africa, Sri Lanka, Suriname, Taiwan, Thailand, Togo, Trinidad and Tobago, Turks and Caicos Islands, United States, Venezuela, Virgin Islands, British Virgin Islands, U.S.
Ecological Region
Mediterranean Sea, Northeast Atlantic Shelf Marine, Southern Australian Marine, Benguela Current, Humboldt Current, Agulhas Current, Western Australia Marine, Gulf of California, Canary Current, Sulu-Sulawesi Seas, Bismarck-Solomon Seas, Banda-Flores Sea, Great Barrier Reef, Palau Marine, Andaman Sea, East African Marine, West Madagascar Marine, Mesoamerican Caribbean Reef, Southern Caribbean Sea, Northeast Brazil Shelf Marine.
Why is this species important?
As a major jellyfish predator, the leatherback turtle provides natural ecological control of jellyfish populations. Overabundance of jellyfish may reduce fish populations as jellyfish can feed on fish larvae and reduce population growth of commercially important fish. Hence, the presence of leatherback turtles benefits fish, fisheries and people.
Interesting Facts
The biggest ever recorded leatherback turtle was a male stranded on a Welsh beach that reached 256 cm long and weighed 916 kg.
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