ABU DHABI // Coral reefs in the Arabian Gulf have deteriorated significantly in the past decade and some of the damage is irreversible, according to a prominent marine scientist.
"All the major indicators are down," Professor Charles Sheppard, from the University of Warwick in the UK, told a marine conservation forum in the capital.
Average fish density, which is 4,000kg a hectare in a healthy reef, is less than 1,000, he said.
Coral reefs sustain a quarter of marine species, despite covering a tiny portion of ocean territory. Shrimp, crab, lobster and many other commercially viable species of fish live on reefs. If reefs disappear, so, eventually, will fisheries.
Prof Sheppard has been studying Gulf corals for more than 20 years and is a reviewing member of the Intergovernmental Panel on Climate Change, the scientific body that informs the United Nations and world leaders.
One of the most striking examples of the severity of the reef damage that Prof Sheppard gave at the forum is Fasht al Adhm, a once-vibrant reef between Bahrain and Qatar.
When he first visited the reef in 1985, "the coral cover at that time averaged 50 per cent or more, which is healthy", he said.
"When we went back two years ago, the coral cover was virtually zero. The reef was covered in seaweed and slime and the corals were disintegrating.
"We went to other reefs around Bahrain and they were all the same," he said.
Prof Sheppard has recorded the damage to Gulf coral in a recent scientific paper, The Gulf: A Young Sea in Decline.
The paper mentions Dubai, where there was once healthy coral off the Deira Corniche and the Dubai aluminium smelter in Jebel Ali. Until 2004, when construction of The Palm Jebel Ali began, the emirate also had the Gulf's second-most biodiverse documented ecosystem.
In Abu Dhabi, the new Khalifa Port and Industrial Zone, projected to have the world's largest aluminium smelter and the biggest plastics and chemicals manufacturing zone, is close to the emirate's most vibrant coral reef, in Ras Ghanada.
In his paper, Prof Sheppard estimated that only three per cent of the Arabian Sea's coral reefs, mainly around the Mussandam Peninsula in Oman, experience low threat levels.
"Reefs and mangroves, in particular, are more threatened here than in any other sea," he wrote.
In his address on Tuesday he explained the reasons for the decline. Large-scale dredging and land reclamation, the process of creating new land from what was once the sea, are major factors, he said.
Others are nutrient-rich discharges from sewage treatment plants, thermal pollution from desalination plants and industry, and overfishing, which can remove herbivore fish that control algae. If algae is allowed to grow unchecked, it can overwhelm coral.
"Usually it is a combination of different factors in varying degrees," Prof Sheppard said.
The problem is that once reefs are destroyed, full recovery is impossible.
"Unfortunately, things are not in our favour," he said. "Even if the problems - sewage, overfishing, landfilling - are solved, when the damage is done, very little can recover."
Efforts to transplant coral from areas about to be affected to safer areas have more of a "feel-good" effect on people, rather than real significance for the marine environment, he said.
"It is better to try to plant them rather than just to bury them and let them die," he said. "But it is a matter of scale."
A translocation scheme can cover one per cent in the best case. In addition, a scheme cannot re-create the coral reef habitat.
"Nobody can transplant a coral reef. What you can do is to try to transplant a few of the corals," he said. "You are making a kind of zoo.
"It is so much better to try to avoid damaging them anyway."
At the same time, however, Prof Sheppard is optimistic for the future.
"It is never too late," he said. "But what we have to do is to step up the information flow. What we need to do is convey it to the people who make the decisions."
Dr Thabit al Abdessalaam, the director of the biodiversity management sector at the Environment Agency - Abu Dhabi, said that if the remaining reefs are to be better protected in the future, there needs to be capacity building "not only at the community level but at the government official and leadership level.
"The issue is not an issue of technological challenge or a management challenge," he said.
What is already known to scientists needs to reach society and decision-makers fast, Dr al Abdessalaam said. The UAE and other Gulf countries need long-term coastal planning, legislation to enable a comprehensive planning system, and networks for information and monitoring, he said,.
The Second Marine Conservation Forum for the Gulf Region, at the Radisson Blu hotel on Yas Island, runs until today. It is organised by the Emirates Wildlife Society - World Wide Fund for Nature.