Endangered: Leatherback Sea Turtle
Part of Hall of Biodiversity.
A Singular Sea Turtle...
More than six feet long, weighing as much as 1400 pounds (636 kg), leatherbacks are the world's largest pelagic (ocean-going) turtles. They are also the only sea turtle with a soft, rubbery shell. (All others have hard, bony-plated shells.) Leatherbacks have special adaptations that allow them to eliminate waste gases through their skin, so they can stay under water for extraordinarily long periods. Inside their bodies, they actually convert salt water to fresh water, ingesting the sea water around them and excreting the salt. Their bodies are insulated by a thick layer of fat -- another adaptation that is unique among turtles to leatherbacks.
CONSERVATION: Use of Turtle Excluder Devices and protection of critical nesting habitats; CITES trade restrictions
...With Multiple Threats
They are strong and graceful swimmers, with powerful front flippers. They spend almost all of their lives at sea, swimming into shallow bays and estuaries to court and mate. The only time leatherbacks come ashore is to lay their eggs, which they do only on sandy, undisturbed beaches.
Leatherbacks are among the most wide-ranging of all vertebrates. They are found in oceans and seas around the world, in habitats ranging from tropical to subarctic. They migrate over long distances, which makes them hard to track and even harder to count. Only the females come ashore and then for just a couple of hours while they lay their eggs. This gives scientists a chance to count and tag them. Current estimates put the worldwide female population at about 100,000. Since males don't come ashore at all, it's virtually impossible to estimate their numbers.
Leatherbacks build their nests on remote stretches of sandy beach. Loss of these coastal nesting habitats is one of the primary threats to leatherback survival.
Fishing is another. Leatherbacks get caught in commercial shrimp nets and suffocate. Turtle Excluder Devices, called TEDs, have been built into some nets that let captured animals escape, but shrimpers complain that TEDs cut down on their catch size. It has been estimated that 11,000 marine turtles are caught in nets every year. Many of them are leatherbacks.
Leatherback eggs are harvested in Malaysia for food, and in some parts of Asia, the turtle is hunted for its oil and flesh.
And then there's the plastics problem. Leather-backs eat twice their weight each day. Their primary food is jellyfish. Unfortunately, they can't distinguish between jellyfish and clear plastic debris, such as sandwich bags. In recent studies, nearly half of all leatherbacks examined had plastic or cellophane in their stomachs. It's not known how much plastic it takes to kill a leatherback, but two facts are clear: no animal can digest plastic, and the amount of plastic in the oceans is increasing drastically every day.
Excerpted from the 1996 exhibition Endangered!