Wednesday, July 30, 2008

News; Swimming For Survival

Slow-moving turtles might not seem like very exciting racers. But this spring, the first-ever Great Turtle Race will pit migrating leatherback sea turtles against each other in a 750-mile (1,207-kilometer) swim to the Galápagos Islands. The race is part of an effort to educate people about the threats facing sea turtles.

In February, Pacific leatherbacks started swimming their way from Costa Rica, where they nest, to the waters near Ecuador's Galápagos Islands, where they feed on jellyfish. Eleven of these turtles were wearing satellite harnesses that tracked their location.

By using this satellite tracking data, the Great Turtle Race organizers will show online viewers the turtles' journey, starting on April 16 and running through April 29. The winner will be the turtle that swam the farthest.

Each of the 11 burly competitors will have its own sponsor for the broadcast, including big companies like Microsoft and Travelocity. The Los Altos, California, Bullis Charter School is sponsoring a turtle with help from the San Francisco-based Gordon and Betty Moore Foundation.

The school's sixth-grade class traveled to Costa Rica this February to help researchers study the turtles. Back at school, students from all grades are learning about these big oceangoing reptiles as part of a special course. They're also working on a blog to help kids across the country learn about leatherbacks. The students named their turtle Saphira, after the female dragon from the book Eragon.

Leatherbacks are the biggest sea turtles on Earth, with some weighing in at more than 2,000 pounds (907 kilograms). "They can be the size of your kitchen table," says Lisa Bailey of Conservation International. They're also ancient—leatherbacks have lived on Earth for about 100 million years.

But today they're in trouble. At sea, turtles can get tangled in fishing nets or suffocate on drifting plastic bags, which they mistake for jellyfish. On the beach, bright lights from hotels and houses sometimes confuse both adult females coming ashore to lay their eggs and hatchlings trying to find their way to the ocean.

These and other problems have caused Pacific leatherback sea turtle populations to drop by 90 percent over the past 20 years. "If we don't do something, they'll be gone in ten years," said Bullis Charter School student Talliya Smith, 11. Smith helped release hatchlings and excavate leatherback nests with her classmates at Playa Grande in Costa Rica. 

The migrating leatherbacks swim more than 750 miles (1,207 kilometers) south to the waters around the Galápagos. Some go even farther south to the colder waters off Chile. Cruising at a rate of more than 43 miles (70 kilometers) per day, they make the trip in about two or three weeks. Once they arrive, the turtles dive to depths of more than 3,280 feet (1,000 meters) in search of jellyfish and other food. In four years, when the turtles are ready to nest again, they'll return to Costa Rica, says sea turtle expert James Spotila.

Saphira, the Bullis Charter School's turtle, is a veteran nester. Since researchers first spotted her nesting at Playa Grande in 1995, Saphira has made 25 nests, averaging 55 eggs in each clutch.

Warren Zhang, 11, and his classmates saw Saphira—who is an amazing 56 inches (143 centimeters) long by 41 inches (103 centimeters) wide—while they were out on turtle night patrol at Playa Grande. "The turtle dug its nest in record time," he said.

The satellite tags that Saphira and her ten turtle competitors carry on their journey will help researchers learn more about where leatherback sea turtles go, even after the online race ends. However, her hatchlings' journeys are more mysterious; researchers think hatchlings drift and feed in offshore ocean currents, but little else is known about what they do until they return to nest for the first time at Playa Grande, which can be ten or more years later.

Check up on the turtles at www.GreatTurtleRace.com, including picking your pre-race favorite beginning April 5.

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