x Abu Dhabi, UAEWednesday 17 January 2018

Turtle recall: Keeping track of threatened creatures

Scientists are monitoring the movements of 20 turtles in the hope of protecting their feeding grounds.

A hawksbill turtle, with a tracking device fitted to its shell, heads back to the water after laying eggs.
A hawksbill turtle, with a tracking device fitted to its shell, heads back to the water after laying eggs.

ABU DHABI // To the untrained eye, they might look like a jumble of lines with no logical pattern. But to marine turtle experts the 20 lines and dots against the backdrop of the Arabian Gulf, shown at the bottom of the page, mark the beginning of an exciting story. For these lines show the movements of 20 hawksbill turtles, which earlier this year were fitted with satellite transmitters on beaches in Iran, the UAE, Oman and Qatar.

The sea creatures, all females, were tagged after they came ashore to lay their eggs. Five of the reptiles were tagged in the UAE. The tagging began in April of this year, when the species begins to lay its eggs. Most of the tagged turtles are known by number only, but some, which have been sponsored by companies, have names. Together with the green turtle, the hawksbill is the most common marine turtle species in the region, but both are listed as critically endangered by the International Union for Conservation of Nature.

The data supplied by the satellite transmitters will help scientists determine what the turtles do after they lay their eggs. And that information is valuable, as not much is known about the foraging grounds that support the creatures in between the laying season. The data provides fascinating insight into the habits of hawksbills, some of which scientists say was previously unknown. The tagged animals initially remain close to where they were tagged. This, said Lisa Perry, programme director for the Emirates Wildlife Society, which organised the tagging in cooperation with the World Wide Fund for Nature (EWS-WWF), was unsurprising, as a turtle lays its eggs in several batches in a period of six to eight weeks in the same general area.

But with the nesting season coming to an end, the turtles are now on the move, looking for feeding grounds. "Already some theories that scientists had have been proved wrong," says Ms Perry. One such theory was that Oman's hawksbills keep to Omani waters and do not enter the Arabian Gulf. But one of the turtles, known on the project's website as number 53003 and tagged on the Dimaniyat Islands in Oman, did just that.

"It went straight into the Gulf, towards Qatar, where we know some foraging grounds exist," said Ms Perry. This is the first time researchers have documented such movement. Qatar is known to be the feeding ground of Gulf turtles, and indeed, said Ms Perry, many of the animals are headed there. Three of the turtles tagged in Iran are now in waters off of Qatar. Two, however, headed to UAE waters.

The five turtles tagged in the UAE have so far stayed in local waters. One of them is Ms EMEG, named after the Emirates Marine Environment Group; she was fitted with a tag at the organisation's nature sanctuary in Jebel Ali. After taking a northerly detour, possibly to avoid Dubai's large offshore developments, she is now swimming in the waters off of Sharjah and Ajman. Three of the UAE turtles - known by the numbers 52982, 52983 and 52989 - are swimming near Sir Bu Nair Island, off the coast of Sharjah, where they were tagged. Researchers say the creatures could be waiting around to lay their last batch of eggs.

Then there is Shelly, tagged off of Sir Bu Nair as well. Adopted by Linklaters, an international law firm with an office in Dubai, which footed the Dh30,000 bill for fitting the animal with a tag. She is heading towards Abu Dhabi. While the turtles will feed during the nesting season, their primary objective is the laying of eggs. Once this is done, they head for their foraging areas to recover. Depending on the availability of food, they nest every four to 10 years, said Dr Nicolas Pilcher, the executive director for the Marine Research Foundation, which is based in Malaysia, and a research partner in the tagging project.

"Overall, females expend a vast amount of energy, not only nesting, but in the physiological development of the egg follicles, then creating the albumen, or the 'egg white', and putting the shells on them," said Dr Pilcher. "Their reproductive activity is driven by the quality of the food resources in the years preceding nesting, not the other way around." That is why it is so important to document and protect the habitats in which sea turtles feed, he said.

"It appears that the southern coast of Qatar, close to the Saudi and UAE borders, is an important foraging ground, as well as some areas 50 to 100 kilometres off of Doha and a few rocky reef areas between Qatar and Bahrain," said Dr Pilcher, who has researched turtles since the 1980s. This week the EWS-WWF is collaborating with conservationists in Saudi Arabia to tag four turtles there, and the overall tagging project will continue for two more nesting seasons, through 2012. You can track the movement of the turtles at www.gulfturtles.com @Email:vtodorova@thenational.ae

Are turtle numbers declining in the UAE? The number has remained relatively constant, with no data suggesting a massive decline or any increase. So why the concern? Because turtles are unique creatures and are quite sensitive to environmental changes. Any disruption in their populations could be hard to discern and evident only after it is too late. What are the main threats? Turtles used to nest in small numbers along the entire UAE coastline, from the border with Saudi Arabia to Ras al Khaimah. But the situation is quickly changing as demand for beachfront hotels and residences grows. But less land on which to lay eggs is not the only problem. One of the biggest dangers is light pollution, a by-product of development. Turtles hatch at night or early morning and need to head for the ocean as soon as they emerge from their eggs. They reach the ocean by following the glow of the moon on the water. The glare from the lights of a hotel, port or neighbourhood often cause them to roam in circles or go the wrong way. Other threats include people and vehicles in nesting areas, the dredging of foraging grounds and plastic waste that ends up in oceans and in which the animals become entangled. How important are turtles to the marine ecosystem? They help to maintain coastal habitats and fish stocks. Green turtles - which, along with hawksbills, live around the UAE - feed mostly on sea grass. By doing so, they keep the grass beds in check, which is good for the ecosystem. * The National