Coral reef settling into new home

posted on 07/06/2009: 70 views

As Dubai develops its coastline, so the marine environment comes under increasing threat. But Gregor McClenaghan discovers that a novel attempt by one major property developer to minimise the environmental impact of its planned coastal project is proving a considerable success

A year after it was dragged 18 kilometres through the ocean to make way for a construction project off Dubai's coastline, a fragile coral reef appears to be adjusting to life at its new home.

The 2,200-square-metre reef had grown for 25 years on the breakwater of Dubai drydock, but was moved last year after the property developer Nakheel announced plans to build a new logistics facility in the area to ship construction materials to The World islands.

Another property firm, Meeras Development, had also planned to build a series of islands near the area occupied by the reef.

Because of the type of coral that had grown over and encrusted the drydock breakwater, it could not be broken off piece by piece and attached to a new home – which was the only way coral had been moved in the past.

Instead, using a previously untried technique, Nakheel glued metal spikes into the rock and concrete and drilled it out in sections, lifting them with a crane then dragging them slowly behind a barge, underwater, to a new home on the breakwater surrounding The World.



"We had about three or four months from start to finish to decide how to do it and complete the move, because we had developers wanting to get to work,” said Brendan Jack, the head of sustainability and environment for the Nakheel project.

"This technique wouldn't have worked on a natural reef, but because the coral had grown on the artificial reef of the drydock breakwater, which was made up of sections of concrete and rock, we could take it out piece by piece.

"Everything had to be done underwater, which was technically difficult – we had to find glue that we could use underwater that wouldn't be toxic to the coral.

"And then, when it came to hooking the sections on to the crane, the crane driver obviously couldn't see what was happening, so the divers had to communicate with a member of their team on the surface who would then relay instructions to the crane.”

Dr John Burt, an assistant professor at the department of natural science and public health at Zayed University in Dubai, has been studying the emirate's coral reefs since 2005. He was brought in as scientific adviser to help Nakheel move the reef, on the condition that his findings would be published in scientific journals independently of the company.

He is now a year into an 18-month research project studying what effect the move has had on the coral. "Most of the reefs in this area have around 35 per cent coral coverage; this reef had 50 to 60 per cent coverage and had 10 times more abundance of juvenile corals than at any of the other three main sites in Dubai, so it was a very significant ecosystem, with 18 species of coral and more than 30 species of fish,” he said.

His involvement in the transplantation involved not only advising on how to minimise damage to the coral during the move, but also monitoring the newly established reef, diving to see how it was recovering one month and three months after the move, and every three months thereafter.

The monitoring project involved tagging 45 coral colonies that would be checked every time, as well as random sampling in different areas. The results, he said, were surprisingly good. "With traditional methods of moving coral you generally get a survival rate of about 30 per cent,” he said.

"In this case, around five per cent of the coral was lost during the move, and after the first month, seven per cent of it showed signs of discolouration, which is a sign that the coral is dying.

"However, in no cases did I see whole colonies die, and by the third month the discolouration was down to about two per cent.

"There was no significant change in the growth rate from when the coral had been at the drydock, and while some colonies did shrink in the first three months, they quickly recovered after that.

"From the ecological side of things, it has been a success – pretty much all of the corals survived.” He said that fish had quickly repopulated the reef in its new location, including two species of damselfish that in Dubai had only ever been seen on the drydock reef.

Economically, however, the project may have been of little short-term benefit following the global financial crisis.

A spokesman for Nakheel confirmed that there were no immediate plans to start work on the logistics facility, while all Meeras Development projects are currently being reviewed.

"We do not disclose details of costs, but we feel this is a relatively small investment to make in comparison to the long-term gains of supporting a healthy marine environment around our projects and the rest of the Dubai coast,” the Nakheel spokesman said.

Dr Burt said that even if the coral had remained in its original home and the developments had not gone ahead, its future was not secure.

"I've been diving in the area for more than 10 years, and the water quality has definitely got worse – there is a major port right next door and there is more algae in the water than there used to be. The corals were not in a good location long- term.

Although recreational divers will eventually be allowed into the area, for now Nakheel is keeping the location of the transplanted reef secret.

"At the moment we don't want to muddy up the scientific study,” said Mr Jack. "We are especially keen not to have commercial fishermen going to the area, but we want people to enjoy the site once it's established and it's the appropriate time.”

The results of Dr Burt's study will be submitted to scientific journals after he finishes gathering all the data in around six months. – The National

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