Washington - About 20 percent of the world's coral reefs are so damaged they are beyond repair, finds a new global assessment of the state of coral reefs released today at the WWF headquarters in Washington, D.C. The damaged reefs no longer provide fish for people or attractions for tourists. At the same time the percentage of reefs recovering from past damage has risen but half of the world's reefs are threatened with destruction, the assessment found. All told, 70 percent of the world's reefs are threatened or destroyed, up from 59 percent four years ago. Climate change, runoff pollution and destructive fishing methods pose the greatest threats to reefs. The Status of Coral Reefs of the World: 2004 involved 240 scientists from 96 countries in the Global Coral Reef Monitoring Network.
"The news is mixed for the world's coral reefs," said Clive Wilkinson, coordinator of the Global Coral Reef Monitoring Network and lead author of the assessment. "We're happy to report that almost half of the reefs severely damaged by coral bleaching in 1998 are recovering, but other reefs are so badly damaged that they are unrecognizable as coral reefs."
The report found that 20 percent of the world's coral reefs "have been effectively destroyed and show few prospects of recovery." The most damaged reefs are in the Persian Gulf where 65 percent have been destroyed, followed by reefs in South and Southeast Asia where 45 and 38 percent, respectively, are considered destroyed. There are also recent reports that many reefs in the wider Caribbean have lost 80% of their corals.
The percentage of recovering reefs has increased compared to the last global assessment. Many of these reefs were damaged in 1998 during an unprecedented "bleaching" when unusually warm water effectively destroyed 16 percent of the world's coral reefs. Most of the recovered reefs are in the Indian Ocean, part of the Great Barrier Reef off the cost of Australia and in the western Pacific, especially in Palau. Earlier this year, Australia increased protection for the Great Barrier Reef from 4 percent to 33 percent.
"This report is a reality check for coral reefs and a helpful guide for the work of WWF and many other organizations dedicated to coral conservation," said Brooks Yeager, vice-president for global threats at World Wildlife Fund. "This report shows that good management can help these amazing reef communities to survive the many stresses they currently face."
The report says the main causes of reef decline are poor land management practices which damage the reefs with sediments, nutrients and other pollutants, over fishing and destructive fishing practices, and coastal development. Other threats loom, especially climate change. Increased water temperatures have already been blamed for the single most destructive event for corals, the 1998 bleaching.
The report includes satellite data from the National Oceanic and Atmospheric Administration's Coral Reef Watch project which measures stress to reefs from temperature. The data show that more bleaching events caused by unusually warm water can be expected in the future.
"It is critical that we develop the ability to monitor and assess the condition of resources, as well as the effectiveness of management actions. The United States, through NOAA, in partnership with global oceans and the marine science community, is committed to the development of an integrated global ocean observing system that will provide resource managers the information they need," said Vice Admiral Conrad C. Lautenbacher Jr, under secretary of commerce for oceans and atmosphere and NOAA administrator. "Working with international, federal, state, academic and private sector partners we have begun to better integrate existing and new coral reef monitoring, mapping and research efforts in the development of coral reef observing systems to provide the type of effective stewardship of our marine resources called for in this report."
The assessment also includes detailed recommendations to preserve and better manage reefs. Some are fairly obvious such as reducing pollution and barring damaging fishing practices such as dynamite fishing which can turn a productive coral reef into a lifeless ocean wasteland. Other recommendations include expanding the use of no-take Marine Protected Areas which cover important spawning grounds. Protecting these "fish nurseries," for example, has shown to increase fishing yields.
The Global Coral Reef Monitoring Network receives support from governmental and non-governmental organizations including the U.S. State Department, National Oceanic and Atmospheric Administration, the World Bank, and WWF to publish this survey of the health of the world's coral reefs and diagnoses solutions for halting and reversing their decline.