Fifth of corals dead: only emission cuts can save the rest, says IUCN

IUCN 10 Dec 08;

The world has lost 19 percent of its coral reefs, according to the 2008 global update of the world’s reef status.

The report, released by the Global Coral Reef Monitoring Network, of which IUCN is a member, shows if current trends in carbon dioxide emissions continue, many of the remaining reefs may be lost over the next 20 to 40 years. This will have alarming consequences for some 500 million people who depend on coral reefs for their livelihoods.

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,” says Carl Gustaf Lundin, Head of the IUCN Global Marine Programme, one of the organizations behind the Global Coral Reef Monitoring Network. “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.”

Encouragingly, 45 percent of the world’s reefs are currently healthy. Another sign of hope is the ability of some corals to recover after major bleaching events, caused by warming waters, and to adapt to climate change threats.

However, 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 occurances 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,” says 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.

“Ten years after the world’s biggest coral bleaching event, we know that reefs can recover given the chance. Unfortunately, impacts on the scale of 1998 will reoccur in the near future, and there’s no time to lose if we want to give reefs and people a chance to suffer as little as possible,” says Dr David Obura, Chair of the IUCN Climate Change and Coral Reefs working group and Director of the Coastal Oceans Research and Development in the Indian Ocean Programme (CORDIO) in East Africa.

A new report on the state of Indian Ocean coral reefs, launched today by CORDIO, an organisation 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,” says Olof Linden of the CORDIO network and Professor at the World Maritime University (WMU), Malmö, Sweden. “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.”

Benefits of coral reefs
Coral reefs provide food, coastal protection, building materials and income from tourism for half a billion mostly poor people. The fish they provide is their main source of protein; the reefs themselves have proved to be an effective natural barrier against storm surges; and diving tourism is an important source of income.

Fifth of world's corals already dead, say experts
Yahoo News 10 Dec 08;

POZNAN, Poland (AFP) – Almost a fifth of the planet's coral reefs have died and carbon emissions are largely to blame, according to an NGO study released Wednesday.

The report, released by the Global Coral Reef Monitoring Network, warned that on current trends, growing levels of greenhouse gases will destroy many of the remaining reefs over the next 20 to 40 years.

"If nothing is done to substantially cut emissions, we could effectively lose coral reefs as we know them, with major coral extinctions," said Clive Wilkinson, the organisation's coordinator.

The paper was issued on the sidelines of the December 1-12 negotiations on a new global treaty on climate change, taking place under the UN flag.

Half a billion people around the world depend on coral reefs for food and tourism, according to a common estimate.

Experts say the coral die-off has several causes, including local pollution, overfishing and invasive species.

But, they say, rising ocean temperatures caused by the greenhouse effect, and acidification, caused by the ocean's absorption of carbon dioxide (CO2) from the atmosphere, are probably the biggest triggers.

"If nothing changes, we are looking at a doubling of atmospheric carbon dioxide in less than 50 years," said Carl Gustaf Lundin, head of the the global marine programme at the International Union for the Conservation of Nature, an umbrella network for more than a 1,000 NGOs and government groups.

"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."

Nearly half of global coral reefs are still healthy, but the overall downward trend shows no sign of stopping, the study found. It added, though, that the damage could be braked by strong conservation measures, such as properly policed marine parks.

Time running out on coral reefs as climate change becomes increasing threat
EurekAlert 10 Dec 08;

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.

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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.

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