This is the VOA Special English ENVIRONMENT REPORT.
Scientists have appealed for international cooperation to protect leatherback sea turtles. The scientists say the world's leatherback population has dropped more than ninety percent over the past twenty years. They warn that leatherback turtles around the world will disappear if current fishing methods continue.
Leatherbacks are the world's largest turtles. They can grow more than two meters long and weigh more than four-hundred kilograms. But they do not have hard, protective shells like most turtles. Their backs are covered with oily, ribbed skin.
Leatherbacks are able to dive almost a kilometer below the ocean surface in search for food. They have survived for millions of years -- since the time of the dinosaurs.
The scientists presented their findings at the yearly meeting of the American Association for the Advancement of Science. Delegates met earlier this month in Denver, Colorado.
Larry Crowder of Duke University told the meeting that leatherbacks are quickly disappearing. He warned that the creatures could disappear within the next ten to thirty years.
Leatherback turtles usually mate every other year. The females swim thousands of kilometers to warm breeding areas. They leave their eggs on the beach at night, then return to the ocean. Many people gather on beaches to watch this event.
For years, experts thought leatherback turtles were safe because they are found in a number of countries. However, recent studies are forcing experts to re-examine this idea.
In nineteen-eighty-eight, scientists found that more than one-thousand-three-hundred turtles left their eggs on the Pacific beaches of Costa Rica. Ten years later, that number fell to just one-hundred-seventeen turtles.
Scientists blame fishing for the sharp drop in the number of turtles. Leatherbacks and other sea creatures get caught in fishing lines. They drown. Or they can be pulled into fishing boats and killed.
In the United States, the federal government and some states have restricted or banned long fishing lines. Scientists say fixing the problem will require efforts by governments and by the fishing industry. They are calling for new fishing agreements to save the leatherback turtles.
This VOA Special English ENVIRONMENT REPORT was written by George Grow.