Coral reefs could recover from tsunami

Posted: 23 March 2006

Most Indian Ocean coral reefs escaped serious damage and could naturally recover from the December 2004 tsunami within five to ten years if damage from human activities, including ill-planned repair work, can be reduced.

This finding come from the most comprehensive report to date on the impacts of the devastating tsunami on Indian Ocean coral reefs. It says that a small number of coral reefs may take 20 or more years to recover, and some individual coral reefs may not recover at all, but the major threats to the reefs of the Indian Ocean continue to be from human activities.

"These human activities include over-fishing, deforestation and climate change," says Clive Wilkinson, one of the editors of the report and Global Coordinator at the Australian Institute of Marine Science.

The tsunami, equivalent to a 100-gigaton bomb, caused unprecedented devastation, killing between 229,000 and 289,000 people, displacing more than a million and causing several billion dollars' worth of damage. Unparalleled in modern times, the wreckage engendered major economic disruption for the countries of the Indian Ocean and serious, although short-term damage to tourism and industry.

Yet, the dramatic effect of the tsunami and the damage to the coral reefs in the Indian Ocean was patchy, depending on the distance of the country from the source of the tsunami, the local bathymetry [or sea depth] and the health condition of the reef. Most of the damage to coral reefs resulted from backwash of debris and sediment from land, including from waste disposal sites.

Man-made stresses

However, the tsunami has caused less damage to coral reefs than the cumulative man-made stresses such as over-fishing, destructive fishing, sediment and nutrient pollution, and unsustainable development.

The report raises a new concern about potential economic damage caused by the ongoing rehabilitation efforts. While immediately after the disaster the main concern was about the potential tsunami damage to coral reefs and the associated livelihoods for millions of people, the unsustainable reconstruction efforts are now moving into the spotlight.

Many of the replacement boats, motors and general fishing equipment use different technology, often leading to inappropriate use and increasing fishing effort.

"There is a major need to sit back and assess what was successful during the whole rehabilitation process and what needs improvement, what lessons can be taken from this experience and what still needs to be put into place before the next coastal disaster," says Wilkinson.

The report, 'Status of Coral Reefs in Tsumani Affected Countries: 2005' was produced by the Global Coral Reef Monitoring Network (GCRMN). This was formed in 1995 as an operational unit of the International Coral Reef Initiative (ICRI).

Related links:

Factfile on Coral reefs

Tsunami disaster highlights need for environmental protection

Coral nears the crisis point