A Global Assessment of Human Eects 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 e€ects of humans on coral reefs are not well understood, especially on a regional or global scale. A special survey protocol called ``Reef Check'' was designed to be used by volunteer recreational divers, trained and led by marine scientists, and based on the use of high value, easily identi®ed indicator organisms. During a period of 2.5 months, a global survey of over 300 reefs in 31 countries and territories indicates that few reefs remain una€ected by man, even very remote sites. Over®shing has reduced ®sh and invertebrate indicator organisms to low levels at most reefs, including those within marine protected areas. The ratio of live to dead coral cover was higher in the Red Sea than 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 detect broad-brush changes on a local, regional and global scale, as well as increasing public support for coral reef conservation. Ó 1999 Elsevier Science Ltd. All rights reserved