Scientists Track Mysterious Green Sea Turtles in the Persian Gulf
Bu Tinah Island, United Arab EmiratesShe was standing on the gunwale in a wetsuit, clinging to an awning with one gloved palm. Then a dark shape emerged and zipped through the emerald water.
Jimena Rodriguez, a marine biologist with the Emirates Wildlife Society-WWF in the United Arab Emirates, bent her knees so she bobbed with the swells as the boat cut out across a sun-baked shoal, 50 miles into the Persian Gulf from Abu Dhabi. Behind her, the boat's captain, scientist Nicolas Pilcher, muttered, "Wait ... wait ... wait." Then he barked: "Now!"
Rodriguez launched herself from the deck, popping up from the water seconds later holding an enormous green sea turtle by the carpace. That afternoon, her fellow researchers would check its health, measure it, and afix a tracking device to its shell to follow its movements as its migrated across the Middle East.
Green sea turtles are found in tropical and temperate waters around the world from South Africa to the Galapagos and from Japan to parts of Canada. But in few places on the planet do we know less about them than along this balmy stretch of the Middle East. And this region is changing quickly.
So in March, off a tiny spit of sand called Bu Tinah Island, where greens come to fatten up on sea grasses before laying eggs, an international team of researchers captured turtles by the dozens, hoping to answer a few basic questions: Where do they nest? How many are there? What can we do to help protect them?
"To understand their longterm trends, we need data," says Pilcher, who runs his own sea turtle research organization in Malaysia and led the spring expedition. "For this region we just don't have it. It's a black box."
Gulf of Change
Greens are one of the most common of the seven global species of sea turtle. They are listed as endangered under the International Union for the Conservation of Nature and protected by the Endangered Species Act and the Convention on International Trade in Endangered Species. They face myriad threats around the world: hunting, pollution, being caught in fishing nets, coastal development, boat strikes. In one of the largest nesting islands in the world, in Australia, warming temperatures are turning almost all hatchlings female, raising important questions about the future.
Still, in other regions, things are looking up. Green populations in Hawaii skyrocketed in recent decades, coming back faster than scientists once thought possible. Hunting and egg-collecting have been curtailed and nesting beaches are now protected.
But scientists here are flummoxed. While they presume green turtle numbers are declining, they have no idea how quickly, or where, or how best to protect them.
"From where I sit, we see the dark side," said David Robinson, operations manager for the Dubai Turtle Rehabilitation Project, a turtle welfare center that operates from the basement of one of the world's most expensive waterfront hotels, the Burj Al Arab. "We get a lot of sick and injured animals, but there's a dearth of information about populations."
Turtles with organ damage from pollution or cracked shells from being hit by ships arrive at his shop from all over the Middle East. They nurse the animals back to health, often only to see them wash up dead later.
"What we're seeing are the physical manifestations of population growth," Robinson said. "The Gulf is under a huge amount of pressure."
Oil development since the 1960s has led to an explosion of development along coastlines in the UAE, Saudi Arabia, Qatar, Kuwait, and other regions. A related explosion of wealth has drawn workers from around the world, bringing more boat traffic and pollution. Along the way, marine life has gotten squeezed.
But figuring out which governments to lobby—and where—to make improvements for turtles is hard enough in the Middle East. Without concrete information it is almost impossible.
So, scientists from many parts of the world have been meeting each spring in Abu Dhabi to try to understand these creatures. It's not easy.
Greens are migratory. They spend time in spring in the warm waters off the UAE, where the Environment Agency of Abu Dhabi often tracks them by air while doing surveys for marine mammals called dugongs. But then they leave.
Every year, about this time, green turtles begin arriving on beaches all across the Persian Gulf. A few dozen often appear in Iran. A handful in Kuwait. Perhaps a thousand will show up in Saudi Arabia.
"The Saudis collected nesting data in the 1980s and 1990s, but they did it sporadically and don't share their data," Pilcher says. "We don't know what the numbers are, what they used to be or if they've changed."
The largest number seem to appear in Oman, where rangers patrol protected shorelines. They crawl to land in late spring in places like Ras Al Hadd. Right now, 5o to 100 turtles a night will be clambering from the water there, onto sandy beaches ringed by bluffs.
Some animals journey even farther. Pilcher tracked one turtle that swam past the Horn of Africa and Djibouti and into the Red Sea.
"We don't know if we're seeing transients or residents," Robinson said. "But we're seeing some amazing journeys, too."
Turtles his organization have rehabilitated and released have disappeared near Pakistan. One swam down to the Maldives and made it near Sri Lanka, clocking an astonishing 5,146 miles before the battery ran out in the tracking device.
So far, this year, Pilcher's group has tracked several turtles headed toward Oman, but not a single one going toward Saudi Arabia.
"We think there's a 20 percent chance of a turtle going north and an 80 percent chance of it going east, but so far everyody's going east," Pilcher says.
That's why this is a multiyear project. Rodriguez, Pilcher, and leaders with Abu Dhabi's environment agency want to get enough data to make recommendations to leaders around the region. Previous studies on hawksbill turtles already have helped Omani and Emirati officials begin rethinking boundaries of some marine protected areas.
"We need to identify areas that are hot spots so governments can use that to know where we need to stop fishing or development or keep people out," Robinson said.
Until then, Rodriguez and Pilcher and others hope to keep capturing and releasing turtles until they unravel more mysteries about their travels.