Unconquered Coral Revisiting the reefs a year after the tsunami    By   Kate Durham

On the sidelines of the human tragedy caused by the December 2004 tsunami, the diving community and environmentalists had serious concerns for the coral reefs in the affected areas. As massive waves receded, they pulled sand, silt, buildings and other debris across delicate marine ecosystems. If the coral wasn’t broken by the flotsam, people feared, it would be smothered under sediment.

The waters had barely receded when organizations all across the world, under the umbrella of the United Nations Environmental Programme (UNEP), rushed to the Indian Ocean to determine the damage. By February 2005, the findings had been consolidated in After The Tsunami: UNEP’s Rapid Environmental Assessment Report.

courtesy World Bank Reef damage was less than expected.

At the earthquake’s epicenter, the Indonesian island of Sumatra suffered the brunt of the tsunami. According to an initial assessment by Wetlands International (WI), a non-profit organization working to maintain and restore wetlands, the areas expected to be most damaged were around the Pulau Aceh (Aceh islands). An April 2005 study by Edi Rudi and Nur Fadli at the Marine Science Center at Syiah Kuala University in Banda Aceh, Indonesia found “no significant impact of [the] tsunami to [the] coral community and no sand or other debris deposited on the coral reef community” around Weh Island, noting that damage was limited to the first three meters below the surface. The WI reported that Banyak Islands coral was still in good condition, while those around Simuelue saw moderate damage.

At the end of October, three marine conservation organizations — The Khaled bin Sultan Living Oceans Foundation, Reef Check and The World Conservation Union — were surveying 600 km of Aceh coastline to determine the damage to the coral reefs.

In Thailand, the coast and islands on the Andaman Sea were hit hardest, particularly around Phuket. However, a January 2005 assessment conducted by the Department of Marine and Coastal Resources, part of Thailand’s Ministry of Natural Resources and Environment (MONRE), noted that damage was localized: “Reefs located in channels between islands suffered higher impacts. Shallow-water reefs are most affected. Deep-water reefs and those around Phuket remain largely intact.” The MONRE report said that several reef sites in Mu Ko Surin National Park had more than 50 percent damage, but a March 2005 survey by Coral Cay Conservation in the park determined “these impacts are extremely localized in nature and do not have a major significant impact on the overall health of the coral reef resources.”

Sri Lanka’s east coast was severely battered by waves up to four meters tall, and UNEP reported that the reefs in Dutch Bay were almost completely destroyed. Even before the tsunami, the Sri Lankan reefs had been severely damaged by human activities, such as blast fishing and coral mining for use in cement. The UN assessment team found that in areas where the coral had been depleted, the tsunami waves were more destructive on land, reporting, “There were signs of absorbed impact and less damage in locations with healthier vegetation and less disturbed ecosystems.”

The Maldives reefs were much more fortunate than the islands themselves. John Gunn, CSIRO, Head of the Maldives Coral Reef Assessment team, reported in March that “the tsunami had very little direct impact on the coral reefs.” Compared to Aceh and Sri Lanka, where massive waves pummeled the coast, Gunn explained that the Maldives experienced “just essentially a rise in sea level.”

A recurring theme in the UNEP and other assessments was the human impact on the reefs. The impact of the tsunami was relatively minimal compared to previous reef damage caused by humans and environmental changes at sites in the Seychelles, the Maldives and Sri Lanka — damage that contributed to devastating consequences on land.

“The tsunami in the Indian Ocean taught the world some hard, shocking but important lessons which we ignore at our peril,” says Klaus Toepfer, executive director of UNEP. “We learnt in graphic and horrific detail that the ecosystems, such as coral reefs, mangroves and seagrasses which we have so casually destroyed are not a luxury. They are life savers capable of defending our homes, our loved ones and our livelihoods from some of nature’s more aggressive acts.”  tt