Coral reefs, which are among the most biologically diverse ecosystems on the planet, are also some of the most ancient. They first appeared in the Mesozoic era some 225 million years ago and some living coral reefs may be as much as 2.5 million ars old.

Outstanding examples of our biological and natural heritage, coral reefs are an important asset to local communities -- serving as a source of seafood, providing materials for new medicines, generating income from tourism, and buffering coastal cities and settlements from storm damage. Yet, in just a few decades, human activities have devastated many of these biologically rich, ancient ecosystems. In the next two or three decades, more are destined for destruction.

Until recently, almost nothing was known about the extent and condition of coral reefs. Unlike the change in rainforests, that in coral reefs is difficult to assess from satellites, and information on their status has been scattered, anecdotal, and relatively inaccessible. The state of knowledge began to improve in 1988, when the World Conservation Monitoring Centre (WCMC) completed work on a three-volume collection of preliminary reports on coral reef problems in 108 nations, which was published by the United Nations Environment Programme and the World Conservation Union.

In 1993, ReefBase, a global database on coral reefs, was established by the International Center for Living Aquatic Resources Management (ICLARM), and WCMC. This resulted in the first global map depicting the location of shallow reefs around the world, published by WCMC in 1996.

Eighty nations now participate in a Global Coral Reef Monitoring Network, to assess the health of reef ecosystems. This network and other efforts will provide a clearer picture of the impact of human activities on coral reefs. However, it will take years to assemble a comprehensive picture of the status of reefs based on field research.

Reefs at Risk: A map-based indicator of threats to the world\'s coral reefs provides the first map-based global analysis of the condition of coral reefs. As such, it marks a significant advance in understanding the condition of coral reefs and should help stimulate further data gathering that will improve subsequent reporting.

This study draws on 14 global datasets that are indicators of development pressure, information on 800 ReefBase sites that are known to be degraded, plus scientific expertise -- to model areas where existing human pressures indicate that reefs are threatened by sedimentation, pollution, overfishing, and other factors.

The analysis offers a stark warning: the pressure of human activities poses grave danger to reefs in most of the world\'s oceans, and irreparable damage is occurring rapidly. The exceptions are places still isolated from intense human pressures and those few places that have implemented effective measures to protect reefs. That is the key. Action is needed, and action is possible to protect these treasuries of ocean wealth.

Many of the protective measures needed to ensure the health of these ecosystems are "win-win" options for both reefs and people.For example, creating marine parks and sanctuaries may enrich local communities by attracting tourists and may benefit nearby fisheries by protecting breeding stock of target species. Eliminating perverse and often costly subsidies to fisheries and agriculture, for example, may reduce overfishing, sedimentation, and pollution of reefs, and building sewage treatment facilities within coastal communities may provide both environmental and health benefits.

We deeply appreciate support for this project from the United Nations Environment Programme, the Swedish International Development Cooperation Agency, the David and Lucile Packard Foundation, the Bay Foundation, the Henry Foundation, and the U.S. Environmental Protection Agency.

Mark Collins, Chief Exective, WCMC
Jonathan Lash, President, WRI
Meryl J. Williams, Director General, ICLARM