However, 46% of the world’s reefs are regarded as being relatively healthy and not under any immediate threats of destruction, except for the ‘currently unpredictable’ global climate threat. Another positive sign is the ability of some corals to recover after major bleaching events, caused by warming waters, and to adapt to climate change threats.

Climate change is considered the biggest threat to coral reefs today. The main climate threats, such as increasing sea surface temperatures and seawater acidification, are being exacerbated by other threats including overfishing, pollution and invasive species.

If nothing changes, we are looking at a doubling of atmospheric carbon dioxide in less than 50 years. As this carbon is absorbed, the oceans will become more acidic, which is seriously damaging a wide range of marine life from corals to plankton communities and from lobsters to seagrasses.

—Carl Gustaf Lundin, Head of the IUCN Global Marine Programme, one of the organizations behind the Global Coral Reef Monitoring Network

The report shows that, globally, the downward trend of recent years has not been reversed. Major threats in the last four years, including the Indian Ocean tsunami, more occurences of bleaching, outbreaks of coral diseases and ever-heavier human pressures, have slowed or reversed recovery of some coral reefs after the 1998 mass bleaching event.

The report details the strong scientific consensus that climate change must be limited to the absolute minimum. If nothing is done to substantially cut emissions, we could effectively lose coral reefs as we know them, with major coral extinctions.

—Clive Wilkinson, Coordinator of the Global Coral Reef Monitoring Network

Corals have a higher chance of survival in times of climate change if other stress factors related to human activity are minimized. Well-managed marine protected areas can also boost the health of coral reefs, but proper enforcement is difficult, especially in remote areas where the most pristine reefs are found.

The report makes a number of summary recommendations, including:

• Urgently combat global climate change. Current rates of climate change pose the greatest threat to the long-term sustainability of coral reefs and human coastal communities.

• Maximize coral reef resilience by minimizing direct human pressures on reefs. The second major threat to reefs derives from direct human activities: over-fishing and destructive fishing; sediment pollution from poor land use; runoff of nutrients and other pollution; and habitat loss through unsustainable development. Control of these threats, which are damaging reefs around the world especially in developing countries including small island developing states, will improve the resilience of coral reefs in the face of climate change.

• Scale up management of protected areas. There is a need to improve the management of existing marine protected areas (MPAs) to accelerate restoration of depleted fish stocks and protect coral reef goods and services that underpin coastal economies and livelihoods. This includes managing adjacent catchment areas to prevent nutrient and sediment pollution to create buffer areas that will reinforce MPA management activities.

• Include more reefs in MPAs. A proven and effective governance approach for conserving coral reefs and promoting sustainable use is to include them in effectively managed MPAs.

• Protect remote reefs. There are many coral reefs remote from continental land masses and human populations that, if they are protected, will be able to act as reservoirs of biodiversity to replenish depleted reefs. The report recommends establishing more MPAs to include many of the remote island reefs, such as those to the west of Hawai‘i, in Kiribati, and the Coral Sea east of the Great Barrier Reef.

• Improve enforcement of MPA regulations. Enforceable governance systems will be required to deal with the formidable problem of regulating access to managed ecosystems (including types and rates of resource exploitation).

• Help improve decision making with better ecological and socioeconomic monitoring.

A second new report, this one on the state of Indian Ocean coral reefs, launched by CORDIO, an organization aligned with the Global Coral Reef Monitoring Network, states an overall trend of continued degradation, only alleviated by signs of recovery in some areas.

With this report, the far-reaching degradation of Indian Ocean coral reefs has become evident. To save coral reefs, we must focus on helping corals to adapt to climate change and on diverting people away from destructive practices such as overfishing.

—Olof Linden of the CORDIO network and Professor at the World Maritime University (WMU), Malmö, Sweden

Resources

• Wilkinson, C. (ed.) (2008) Status of Coral Reefs of the World: 2008