What Are We Doing to Our Reefs?

For more than a decade, divers worldwide have reported rapidly increasing damage to reefs, but there has been little scientific data supporting their observations. Now, thanks to 750 volunteer divers and 100 marine biologists, Gregor Hodgson, coordinator of Reef Check, says "we have evidence that coral reefs are being plundered on a global basis."

In fact, Reef Check, the first global survey of reefs ever made, has found that 95 percent of the world's coral reefs have been damaged by overfishing, dynamiting, poisoning, pollution, or ships' anchors.

The Reef Check survey, which was sponsored by the Marine Conservation Society, was carried out last summer at 300 sites in the Caribbean, the Indo- Pacific, and the Red Sea. It revealed that populations of fish and shellfish once common to the reefs it studied have been decimated on most of them. On each reef studied, teams examined an area of coral roughly the length of a football pitch. They checked numbers of 20 key species and looked for evidence of coral damage from sewage pollution, cyanide fishing, and anchor destruction.

The most severely affected reefs were in the Indo- Pacific, where demand for reef fish -- a gourmet delicacy in Hong Kong and southern China-- has stripped reefs of many large species. The Napoleon or humphead wrasse and Barramundi cod were once moderately abundant on Indo-Pacific reefs, but none were reported at 85% of the 179 reefs surveyed in the region. Although more than 25 kilometers of Indo-Pacific reef were surveyed, only 26 humphead wrasse were seen. Cyanide and other forms of fishing had severely damaged populations of this species, which was formerly found in moderate abundance there. (Areas in the Maldives and the Red Sea, where there was no fishing with poisons or explosives, had bigger fish populations.)

Lobsters were also scarce in the region. Only 25 were found in the 179 Indo-Pacific reefs surveyed, 11 of them at a single reef in an Indonesian marine reserve. In all, the Indonesian Institute of Science found that 42% of Indonesian coral reefs have been damaged and that only 6% are in excellent condition.

Sadly, worldwide statistics aren't a whole lot better. No lobsters were found at 81 percent of the reefs surveyed worldwide, and 40 percent of reefs had no grouper longer than a foot. Large grouper are heavily fished world round, and none were reported at 40% of the reefs studied. The rest had small numbers at best. (The Maldives and the Red Sea, where no poisoning or dynamiting occurs, were also an exception to this trend. More than 20 large grouper were recorded at survey sites in these areas.) Out of 51 Caribbean reefs surveyed, the once-common Nassau grouper was found at only four sites, and the total count was only 12 fish. In the Seychelles, Dr. Elizabeth Wood noted that "we found no lobsters on the sites we surveyed, and valuable shells such as giant triton have also been over-collected -- we found none of these either."

"Coral reefs on a global basis have been pretty well wiped out as far as these high-value edible species go," says Hodgson. "The results are very shocking."

If there is any positive side to the study results, it is that this sort of information is vital if countries are to be convinced to protect their reefs before it is too late. Says Herman Cesar of the World Bank's Coral Reef Rehabilitation Program, "the Indonesian government does not realize that if coral reefs are destroyed, the value of Indonesian reefs, which can generate 2.3 billion dollars in annual income, would diminish seriously." However, it's just this kind of information that has led the Philippines to set up a legal system which makes it easier to bring violators to court. As a result, Cesar said, cyanide fishing there has decreased significantly.

-- from various news sources, including New Scientist

Next issue: What YOU can do to help save the reefs.