Increasing pressures from climate change will reach a tipping point in less than a decade triggering a significant decline in the health of the planet's coral reef ecosystems according to the findings in an international report issued today.
Released by the Global Coral Reef Monitoring Network and the International Coral Reef Initiative, international governmental and scientific partnerships, "Status of Coral Reefs of the World: 2008" provides both good and bad news while sounding the call for urgent global action to respond to climate change.
Coral reefs continue to be threatened from direct human activities of pollution and over-fishing, but now the threat of climate change is being recognized as the major threat to the future of reefs around the world. One fifth of the Earth's coral reefs have disappeared since 1950, and a NOAA authored report issued in July states that more that that nearly half of U.S. coral reef ecosystems are considered to be in "poor" or "fair" condition.
"Unless the world gets serious about reducing greenhouse gas emissions in the next few years, it is likely there will be massive bleaching and deaths of corals around the world," notes the report's lead editor and global coral authority Clive Wilkinson who coordinates the Global Coral Monitoring Network in Australia. "This will have significant impacts on the lives of the people in developing countries who are dependent on reefs for food, for tourism, and for protecting the land they live on."
This status report was put together from 370 contributors in 96 countries and states and is the most authoritative report on the world's coral reefs. The report presents regional assessments of the health coral reef ecosystems found throughout the world, the threats they face, and recommendations for action. A new feature of the 2008 reporting is publication of a separate report, "Socioeconomic Conditions along the World's Tropical Coasts: 2008," detailing socioeconomic data on how people use coral reefs in 27 developing tropical coastal countries.
The status report includes satellite date from NOAA's Coral Reef Watch project which measures stress to reefs from temperature globally and resulting bleaching. NOAA recently started tracking ocean acidification changes in the Caribbean.
Frequent or long-term bleaching kills or severely weakens corals, leaving them more vulnerable to disease, and resulting in a sea bottom covered with algae and sponges that may eventually smother remaining coral. Acidification is a growing threat that could imperil the ability of corals to build their skeletons. A number of recent studies demonstrate that ocean acidification is likely to harm coral reefs by slowing coral growth and making reefs more vulnerable to erosion and storms.
In good news the report, which is issued every four years, found that there was major recovery of reefs in the Indian Ocean and western Pacific from climate change induced bleaching events in 1998 - especially those reefs that were in protected areas. Other reefs cited as being in healthy condition included Australian reefs in general, most notably the Great Barrier Reef, the remote reef systems of the Pacific and Indian Ocean that suffer little human impacts and some small areas of the Caribbean.
The report also acknowledges that increased awareness such as that promoted by 2008 being designated "International Year of the Reef" is beginning to have an impact pointing to a series of major conservation initiatives that have been announced in recent years including the Coral Triangle Initiative in Asia, the Micronesia and Caribbean Challenges, and the creation of the two largest marine protected areas in the world: in the Phoenix Islands of Kiribati and the U.S. Papahanaumokuakea Marine National Monument.
In addition to climate change, negative impacts to corals in the past four years included the Indian Ocean tsunami, hurricane damage which combined with bleaching has endangered wide ranges of Caribbean coral reefs, and increasing human activity pressures including pollution, development, deforestation and overfishing in East Africa, South Asia, Southeast Asia, populated areas of the Pacific and Caribbean. One particular threat is the increase in "bomb" and cyanide fishing in Asia and in Tanzania.
The assessment includes detailed recommendations to preserve and better manage reef ecosystems. Human pollution and fishing pressures have to be reduced while the development of sustainable tourism activities can protect the reefs while stimulating economic growth. The report also encourages increased use of marine protected areas as a means of ensuring reefs can continue to protect important fish nursery areas and serve as reservoirs of marine biodiversity.
The Global Coral Reef Monitoring Network receives support from governmental and non-governmental organizations including the U.S. Department of State, NOAA (the National Oceanic and Atmospheric Administration), the World Bank and the WWF (World Wildlife Fund) to publish this survey of the health of the world's coral reefs and diagnoses solutions for halting and reversing their decline.