LEATHERBACK SEA TURTLE } Dermochelys coriacea
DESCRIPTION: The leatherback sea turtle is distinguished by its soft, leathery shell, which is predominantly black and made of tough, oil-saturated connective tissue. Its flippers lack claws and are the largest, in proportion to body size, of any sea turtle. As the largest living turtle species, the leatherback reaches up to 10 feet in length and weighs an average of 500 to 1,500 pounds.
HABITAT: Leatherbacks are deep-water turtles but also forage in coastal waters. Temperature adaptations allow this species to travel to far northern and southern reaches of the world’s oceans — areas that are unexplored by other sea turtles.
RANGE: Leatherbacks are found in all tropical and subtropical oceans. They have been found as far south as the southernmost tip of New Zealand and as far north as the Arctic Circle. Leatherbacks are known to migrate thousands of miles between nesting and feeding grounds.
MIGRATION: In the Pacific, there are two populations. The West Pacific population breeds in New Guinea and Indonesia (it is virtually extinct in Malaysia), travels across the North Pacific past Hawaii, and feeds off California and Oregon in late summer and fall. The East Pacific population breeds in Mexico and Costa Rica and heads to its feeding grounds near the Galapagos and off South America in summer. In the Atlantic, the turtles breed in Florida, the Caribbean, and South America in the western Atlantic and along the coast of West Africa in the eastern Atlantic. They wander all across the Atlantic, appearing as far away as England.
BREEDING: Though male leatherbacks never leave the water once they enter it, females crawl onto sandy, tropical beaches to lay their eggs. Female leatherbacks nest several times during a season, laying clutches of approximately 100 eggs each. After two months, white-striped leatherback hatchlings emerge from the nest. Hatchlings make their way to the ocean, orienting themselves toward the brightest direction, which on natural, undeveloped beaches is toward the open horizon of the sea.
LIFE CYCLE: Leatherback sea turtles reach sexual maturity at five to 15 years and live 45 years or more.
FEEDING: Leatherbacks lack the chewing plates characteristic of other sea turtles. Unable to feed on crustaceans and hard-bodied prey, the leatherback’s diet is mainly made up of jellyfish. They also feed on sea urchins, squid, fish, blue-green algae, and floating seaweed.
THREATS: The primary threat to leatherback sea turtles is incidental bycatch in longline and gillnet fisheries. Other threats include coastal development, beachfront lighting, increased nest predation, habitat degradation, ocean pollution, collisions with watercraft, and global warming.
POPULATION TREND: Once numbering more than 100,000 nesting females, the leatherback sea turtle has suffered exponential declines in recent years. In the Pacific Ocean, fewer than 2,000 adult females now remain, and studies suggest that the Pacific population may become extinct within as little as a decade. The Mexico leatherback nesting population, once considered to be the world’s largest, is today less than 1 percent of its estimated size in 1980. Leatherbacks in the Atlantic Ocean are in better shape than in the Pacific, with some nesting populations actually increasing.
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