World Wildlife Fund

From sand to sea and back again, marine turtles travel the Earth. WWF’s tracking of two green turtles reveals a bit about their life in the water in the decades between heading out to sea as hatchlings and returning to the beach as adults to give birth to the next generation.

Sea turtles have made this planet home for far longer than humans have. Living in the oceans for over 100,000 years, these resilient creatures survived the last glacial period and the extinction of the dinosaur. But now they themselves are in danger of extinction. Sea turtles face many human-induced threats: widespread poaching for their meat, shell and eggs; habitat destruction; pollution; bycatch; and collisions with boats. As a result, some turtle populations have been entirely wiped out and others severely reduced. Six of the world’s seven species of sea turtle are classified as either endangered or critically endangered; the status of the seventh is unknown.

WWF is taking action to save the endangered green sea turtles and their fellow ancient mariners around the globe. From the seas along Coastal East Africa to the lush waters of the Coral Triangle, we have been using satellite technology to track sea turtles during their undersea migrations. The data we collect from this work tells us exactly where the turtles go once they leave their nesting grounds on shore. We turn this information into detailed maps – extremely valuable tools we use to improve turtle conservation, demonstrate the need for protected areas, and influence policy. Just as important, we can use the information to encourage communities to partner with us in conservation efforts.

After decades in the sea, the adult female green turtle returns to the each where she was born. With her hind flippers, she digs a deep hole and lays as many as 200 eggs. Roughly two months later, hatchlings emerge and scramble in a mad rush to the sea. The ones shown here are in the Turtle Islands Park, which WWF helped develop.
© WWF-Canon/Jürgen Freund;

Late in the summer of 2007, WWF began tracking the migrations of two female green turtles – affectionately named Marina and Carolina – in the Coral Triangle. This work is part of a larger tracking program that follows greens and critically endangered hawksbill and leatherback turtles.

Marina’s Trip Marina is a 193-pound green turtle whose curved shell measures about 3 feet in length. WWF scientists found her on Sangalaki Island on August 13, 2007, laying her clutch of eggs. Before she reentered the sea to resume her migration, we fitted her with a lightweight satellite transmitter. We tracked the signal, and at the end of the transmitter’s three-month battery life Marina had migrated almost 680 miles. She stayed quite close to the coastline along Indonesia and Malaysia, stopping along the way in a number of MPAs WWF helped establish (green areas on the map), including the Turtle Islands Park and her last-recorded location in the proposed Tun Mustapha MPA.

Carolina’s Trip Carolina is a good deal larger than Marina; her shell measures 3 feet, 8 inches and she weighs an impressive 331 lbs. This indicates that she is probably older than Marina. Carolina was fitted with a transmitter and left Sangalaki on the same day as Marina. However, her migratory path was far different. Typical of an older turtle, Carolina headed out into open waters, moving up through the Sulu Archipelago. When her transmitter gave out at three months, she had logged 1,100 miles and was near Basilan Island in the Philippines. There are currently no MPAs in this region, where continued armed conflict has limited the opportunities for conservation action.

What Tracking Turtles Tells Us Marina’s coastal journey took her through established MPAs that WWF worked hard to secure. The story of her migratory route is an example of the importance of these MPAs to critical feeding and nesting areas for these wide-ranging animals. We continue to work for the creation of additional MPAs along the Indonesian and Malaysian coastlines, to build a network of effective protection. Carolina’s travels illustrate the extensive turtle migration area in the Coral Triangle’s open seas. We are promoting the establishment of a network of MPAs across the waters around the Philippines. The enforcement of regulations in MPAs helps reduce poaching levels and accidental capture in fishing gear – not only for turtles, but for many other marine species.

The tales of these two ancient mariners, along with the stories of dozens of other turtles and related biological data, contribute another layer of scientific knowledge about the needs of these species. The more we know about them, the better we can tailor our efforts to ensure that they are in fact swimming toward survival.