A global assessment of human effects on coral reefs

Coral reefs have been used by humans as recreation areas and as a source of food and other products for thousands of years. The effects of humans on c oral reefs are not well understood, especially on a regional or global scal e, A special survey protocol called "Reef Check" was designed to be used by volunteer recreational divers, trained and led by marine scientists, and b ased on the use of high value, easily identified indicator organisms. Durin g a period of 2.5 months, a global survey of over 300 reefs in 31 countries and territories indicates that few reefs remain unaffected by man, even ve ry remote sites, Overfishing has reduced fish and invertebrate indicator or ganisms to low levels at most reefs, including those within marine protecte d areas. The ratio of live to dead coral cover was higher in the Red Sea th an in other regions, indicating that reef corals are in the best condition there. In future years, by increasing the number of reefs and the frequency of surveys, the Reef Check program could provide a valuable method to dete ct broad-brush changes on a local, regional and global scale, as well as in creasing public support for coral reef conservation. (C) 1999 Elsevier Scie nce Ltd. All rights reserved.