A leatherback sea turtle swims across half the planet

After 647 days of swimming, the animal finally reached the cool waters of the Pacific Northwest—where a feast of jellyfish awaited.

Little had been known about the migratory routes of leatherbacks that nest in the western Pacific region, including some of the largest remaining nesting populations in Indonesia, Papua New Guinea, and the Solomon Islands.

Scott Benson of NOAA's Southwest Fisheries Science Center in Moss Landing, California. and his colleagues used satellite technology to track nine leatherback turtles from a previously unstudied population nesting on the beaches of Jamursba-Medi in the Indonesian province of Papua.
Transmitters were attached to nesting females using a backpack-like harness made of nylon webbing. The transponders sent signals to satellites every two days, allowing the scientists to record diving behavior, sea temperatures, and high-resolution geographic positions. Some of the turtle's dives sent it plunging into the cold darkness 3,300 feet (1,000 meters) below the ocean surface. While three animals traveled westward into the South China Sea, one turtle moved north to the Sea of Japan. The remaining turtles traveled eastward, though only the one animal made it all the way across the Pacific Ocean. This provides the first record of a trans-Pacific migration by a leatherback and is the longest recorded migration of any sea vertebrate.
"We had always assumed the leatherbacks occasionally spotted off California were from Mexico," said study co-author Peter Dutton, also with NOAA's Southwest Science Fisheries Service. "Now we realize that conservation efforts need to be expanded across the ocean to the western Pacific breeding sites."
"Leatherbacks are global mariners that don't recognize international boundaries," Benson added.