Just Leave Phuket's Coral Reefs Alone!

[george]

Just leave Thailand's tsunami-damaged coral reefs alone say scientists

Thailand's rush to grow its tourism industry led to overdevelopment and eco-unfriendly infrastructure that damaged coral reefs.

PHUKET, Thailand (14 May 2005) -- The best way to regenerate the scores of Asian coral reefs battered by the devastating tsunami of December 2004 is simple, say conservation bodies - leave them alone.

A new advisory report, commissioned by the World Bank, argues that governments should focus the scant resources available on minimising over-fishing and other hindrances to natural recovery, rather than launching into costly artificial reef-restoration projects.

Up to 20% of 174 sites now surveyed in Thailand were badly affected by the tsunami, with 13% being severely damaged, says marine biologist Alasdair Edwards, who chairs the World Bank's Coral Restoration and Remediation Working Group. Levels of destruction are likely to be similar in Sri Lanka, he says.

A separate study completed in March by the Coral Cay Conservation group found that just 8% of reef coverage in western Thailand's Surin Islands had been lost.

Localised destruction

In most cases, the damage was caused by debris carried onto the reefs by the backwash that occurred when the tsunami waves retreated. Sediment, trees, rubble, cars and other debris were dragged into the ocean, but the damage was often quite localised. For example, the north of Patong Bay in Phuket, Thailand, was almost untouched, says Edwards, while reefs in the south of the same bay were severely impacted.

Despite the widespread damage, there is no evidence to suggest most reefs will not recover naturally, says Edwards, based at the University of Newcastle upon Tyne, UK. The report's authors point out that corals damaged by typhoons and cyclones in the past have recovered without human intervention.

But Edwards notes that a few "simple, low-cost interventions" could be useful, such as clearing reefs of man-made debris, and righting some of the massive, overturned corals.

The World Bank requested the advice following concern about engineering techniques being proposed to governments by commercial organisations in the region. Suggestions included the installation of artificial concrete and wire reefs and schemes to cement corals back into place.

Quick fixes

Similar recommendations were made by others at a meeting of the International Coral Reef Initiative in the Seychelles in April. ICRI is a global partnership of bodies, including governments, tasked with preserving coral reefs.

"The area of reefs damaged during these events is often vast," said a resolution put forward at the meeting. "Naturally governments and the private sector with economic interests in coral reefs will seek quick solutions based on engineering principles to repair the damage."

But Edwards told New Scientist that, while "quick fixes are being offered to governments, these restoration projects are totally unproven. Coral reefs have been subject to natural disasters for millions of years, and they have survived."

Craig Turner with the Coral Cay Conservation group in London, UK, agrees with the new report: "Governments should concentrate their scant resources on reducing the other threats to reefs", such as pollution and fishing with explosives. He says the CCC's March study revealed the beginnings of regeneration - just eight weeks after the disaster.

--The Scientist 2005-05-15