Dermochelys coriacea
Scientific Name:-
Dermochelys coriaceaCommon Name:-
Leatherback turtle / Leathery turtle
Malayalam Name:-
Leatherback Kadalama
Category:-
Sea turtles
Status:-
Critically Endangered A1abd ver 2.3 in Red Data Book; Appendix I of CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora); and CMS, the Convention on Migratory Species (listed on Appendices I and II). Indian Wildlife (Protection) Act: Schedule I.
Description:-
This is the largest living sea turtle of the world. Adults are easily distinguished from all other species of sea turtles by their spindle-shaped huge bodies and their leathery, unscaled keeled carapaces. The carapace is dark grey or black with white or pale spots, with 7 distinct ridges running the length of the animal, while the plastron is whitish to black and marked by 5 ridges. The head of the adult leatherback is small, round and scaleless. Head has feeble beak; upper jaw deeply notched, with 2 cusps; lower jaw with a single, pointed central hook that fits between the upper cusps, when the mouth is closed, giving the appearance of a W in front view. Their diet is almost exclusively jellyfish. Males are distinguished from females mainly by their longer tail; they also seem to have a narrower and less deep body. Apart from their short tail, females have a pink area on the crown of their head.
Leatherbacks prefer open access beaches with a steep slope and rock free deep water approach. Leatherbacks usually nest once in every 2 to 3 years, though there have been reports of them nesting annually. A female may nest between 6 to 9 times per season, with an average gap of 10 days between nestings. A clutch consists of an average of 80 fertilised eggs (about 5 cm in diameter), which are covered with a layer of about 30 smaller, unfertilised eggs in each nest. Incubation takes about 65 days.
Threats:-
The greatest threat to the species in India is incidental catch in fishing nets. They are frequently caught in southern Kerala and meat consumption has been reported. Further, habitat destruction in nesting beaches is another threat to these turtles. Pollution, especially those by plastics is another cause of mortality.
Remark:-
Though it was believed that leather back turtles are strictly epipelagic, recent tagging studies confirm that this species frequently descends into deep waters and that it is physiologically well adapted to deep-diving.
Habitat:-
Leatherbacks are the most migratory and wide ranging of all sea turtles. The Leatherback turtle has a worldwide distribution. It is found from tropical to sub-polar oceans; nests on tropical (rarely subtropical) beaches. Very little is known about the distribution of post-hatchlings and juveniles. Nest on sandy beaches. The juveniles may remain in tropical waters warmer than 26°C, near the coast, until they exceed 100 cm in curved carapace length. The leatherback turtle is a highly pelagic species that approaches coastal waters only during the reproduction season.
Synonyms:-
Testudo coriacea Linnaeus, 1766; Testudo coriaceous Pennant, 1769; Testudo arcuata Catesby, 1771; Testudo lyra Lacépède, 1788; Testudo marina Wilhelm, 1794; Testudo tuberculata Pennant in Schoepf, 1801 ; Chelone coriacea Brongniart, 1805; Chelonia coriacea Schweigger, 1812; Chelonia lutaria Rafinesque, 1814; Dermochelys coriacea: Blainville, 1816; Sphargis mercurialis Merrem, 1820; Coriudo coriacea Flemming, 1822; Chelonia Lyra Boryde St. Vincent, 1828; Scytina coriacea Wagler, 1828; Sphargis tuberculata Gravenhorst, 1829; Dermochelis atlantica LeSueur in Cuvier, 1829; Dermatochelys coriacea Wagler, 1830; Gadow, 1901; Dermatochelys porcata Wagler, 1830; Sphargis coriacea Gray, 1831; Chelyra coriacea Rafinesque, 1832; Testudo coriacea marina Ranzani, 1834; Dermatochelys atlantica Fitzinger, 1836 (1835); Testudo (Sphargis) coriacea Voigt, 1837; Dermochelydis tuberculata Alessandrini, 1838; Chelonia (Dermochelys) coriacea van der Hoeven, 1855; Testudo midas Hartwig, 1861; Sphargis coriacea var. Schlegelii Garman, 1884; Dermochely coriacea Boulenger, 1889; Sphargis angusta Philippi, 1889; Dermatochaelis coriacea Oliveira,1896; Dermochelys schlegelii Stejneger, 1907; Dermatochelys angusta Quijada, 1916; Dermochelys coriacea coriacea Gruvel, 1926; Dermochelys coriacea schlegeli Mertens andMüller, 1934.
References:-
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