Coral reefs in much of the Pacific Ocean are dying faster than thought, with little difference between well-protected and poorly managed areas, says a study released Wednesday.

Researchers from the University of North Carolina examined some 6,000 surveys of more than 2,600 coral reefs in the Indo-Pacific — stretching from the Indonesian island of Sumatra to French Polynesia — conducted between 1968 and 2004.

Australia's Great Barrier Reef is just as susceptible to coral reef loss as the poorly-managed marine reserves in the Philippines, the study found.
(Associated Press)

They found coral coverage there has fallen by 20 per cent in the past two decades. About 1,500 square kilometres of reefs have disappeared since the 1960s, the study found.

"We found the loss of reef-building corals was much more widespread and severe than previously thought," said John Bruno, who conducted the study along with Elizabeth Selig. "Even the best managed reefs in the Indo-Pacific suffered significant coral loss over the past 20 years."

Little difference was found between the loss of coral in Australia's well-protected Great Barrier Reef and in ill-protected marine reserves in the Philippines, the researchers said.

The United Nations has said nearly one-third of the world's coral has disappeared, and expects 60 per cent to be lost by 2030.

Reefs play economic, cultural role

The Indo-Pacific contains about 75 per cent of the world's coral reefs.

Coral reefs provide a key source of income for island communities from fishing and tourism, as well as sheltering low-lying islands from storms.

"Indo-Pacific reefs have played an important economic and cultural role in the region for hundreds of years and their continued decline could mean the loss of millions of dollars in fisheries and tourism," Selig said in a statement. "It's like when everything in the forest is gone except for little twigs."

The study didn't examine the cause of the decline, but the researchers said they believed it is due to climate change, coastal development and disease.

Bruno said the study demonstrated the need to better manage reefs and prevent threats such as overfishing, but acknowledged local measures would have little impact without a reduction of greenhouse gases.

"It is just one more example of the striking, far-reaching effects of climate change and our behaviour," Bruno said of the link between climate change and reef destruction.

"It is the folks in North Carolina driving their SUVs. It is their behaviour that is having an effect way out in the Indo-Pacific."

With files from the Associated Press