NOAA's Reporter's Coral Reef Tip Sheet
October 13, 1997 - Week 41

The results of the first global survey of human impacts on coral reefs has just been announced in Hong Kong. The survey, Reef Check '97, has been completed as part of the International Year of the Reef. Organized by Hong Kong University of Science and Technology's Institute for Environment and Sustainable Development, the survey involved more than 100 marine scientists and 750 recreational divers who surveyed 300 coral reefs in 30 countries and territories between June and August of this year.

The survey found that the mean percentage of living coral cover on reefs was 31% globally, with the Caribbean recording the lowest value at 22%, possibly reflecting recent losses due to bleaching and diseases. In the Red Sea, there was less than half the dead coral (3%), than the other two regions. The ratio of live to dead coral was highest in the Red Sea, suggesting that these reef corals are the healthiest in the world.

One apparent bit of good news is that only 7 sites showed greater than 10% cover of fleshy algae, indicating that nutrient enrichment associated with sewage pollution was not a problem at most of these "good" sites. Sewage pollution may be more important at reefs near urban areas which were not common in this study.

45% of the reefs were rated as being subjected to low or no human impacts. In contrast, the low numbers of fish and shellfish recorded in the surveys indicate that almost all sites have been affected by heavy fishing of one or more indicator species. One reason for this is that many fishing activities occur at night, when sport divers are not present. In some areas such as the east coast of Borneo, the reefs had not been previously surveyed, and some scientists previously assumed that they would still be untouched. But according to the Sarawak Reef Check team, "99% of the reefs have been damaged by blast fishing."

According to Global Coordinator and coral reef biologist Dr. Gregor Hodgson, these results are an urgent reminder that "ocean resources are not limitless." The low numbers of edible and collectible indicator species is strong evidence that "coral reefs have been plundered on a global basis." The good news is that results from marine parks with proper management demonstrate the effectiveness of conservation to allow populations of indicator species to recover. High numbers of indicator species were reported from marine protected areas in several countries.

The project was badly needed, according to Dr. Hodgson "because coral reefs are the rain forests of the sea. They are one of the world's most valuable natural resources, a storehouse of billions of dollars worth of genetic material for drugs and an important factor in coastal protection. They are a tourist attraction for 7 million sport divers and a source of food for several hundred million people. "Sadly," says Hodgson, "since 1990 we have been getting reports from sport divers of rapidly increasing damage to reefs all over the globe, but scientific data have been lacking." The few hundred reef scientists in the world study many different aspects of the reef, at different times and places.

Traditional coral reef science has not kept pace with the spreading effects of humans on reefs. A new approach was needed to quickly gather comparable data on human impacts from many reefs at the same time. The Reef Check approach was to create a global network of regional, national and local coordination centers, each being responsible for matching up teams of experienced recreational divers with professional marine scientists. Each Team Scientist was responsible for training the team divers in use of Reef Check methods, then leading them on the actual field surveys, checking and submitting data to headquarters in Hong Kong.

For more information contact Reef Check
http://www.ust.hk/~webrc/ReefCheck/reef.html

All coral reefs showed signs of human activities, and few reefs were in excellent condition. No pristine reefs were found. Even very remote reefs had been heavily fished for sharks, lobster, giant clam and, most worrying, large predator fish species such as grouper and sweetlips. In many areas of Southeast Asia, high-value target species were completely absent. The results were the first scientific confirmation of what recreational divers have been reporting for several years -- coral reefs are being abused by man on a world-wide basis.

FOR MORE INFORMATION ABOUT THE INTERNATIONAL YEAR OF THE REEF , PLEASE CONTACT: