Coral Decline - Brief Article

THE WORLD'S CORAL REEFS FACE EXTINCTION IF RADICAL ACTION ISN'T TAKEN.

SHORTLY BEFORE LAST year's highly-publicised Climate Conference in the Hague, a panel of the world's most eminent coral reef scientists issued a stark warning that illustrated lust how widespread the effects of climate change will be. Among its many other negative effects, they warned, will be the death of reefs all over the world as a result of warming seas.

Speaking towards the close of the 9th International Coral Reef Symposium, one of the Olympic events of marine science, attended by nearly 2,000 top researchers from over 50 countries, the panel painted a picture of almost unremitting gloom and called for decisive action.

'We call for an effective reduction in greenhouse gas emissions over the next decade', said Yossi Loya, Professor at the Department of Zoology at the Faculty of Life Sciences at Tel Aviv University in Israel and the recipient of the Year 2000 Darwin Medal for Lifetime Contribution in Coral Reef Research.

The biggest warning sign so far that the world's corals are in serious trouble was the massive coral bleaching that occurred in 1997-98. In large areas of the Indian Ocean, more than 90 per cent of the corals died. Coral bleaching occurs when the symbiotic algae that live in corals become stressed and are expelled. This turns corals white, leaving them in an unhealthy state. Research presented at the conference revealed that rising temperatures have been responsible for large scale bleaching and mortality events in 1999 and 2000.

Such death rates are virtually unprecedented. And the overwhelming majority of scientists at the symposium agreed that climate change is the cause.

Reef-building corals have created the richest and most biodiverse habitats on earth. It is estimated they contribute at least US$400 billion a year to the world economy, forming an essential part of the livelihoods of around 500 million people. Living reefs also protect vulnerable coastlines from sea surge; an almost priceless service.

'We are not appreciating the true economic value of these resources,' says Hugh Kirkman, who directs UNEP's East Asian Seas Regional Coordinating Unit, 'and too often our efforts are like sticking band-aids on a great wound.'

The Global Coral Reef Monitoring Network presented a report on the status of the world's reefs to the Symposium. It concluded that, only two years after a survey of the world's coral reefs found 11 per cent had been destroyed by human activity, a more extensive assessment by around 80 countries of their own reefs had raised the total to 27 per cent 'effectively' lost by late 2000. 'At least another 25 per cent will be lost within twenty years', said Clive Wilkinson of the Australian Institute of Marine Science, who edited the report.

'The fact that all major climate models show that the current increases in sea temperature will continue, is a source of major concern', said Professor Ove Hoegh-Guldburg of the Centre for Marine Sciences at the University of Queensland, Australia. 'We have insufficient evidence that corals are able to accilmatise or adapt fast enough to these sort of changes. This is a clear area for priority research'.

'There have been similar rates of climate change in geological history, and we are able to explain these by natural phenomena', said Mark Eaken, Director of Paleoclimatology for the National Ocean and Atmospheric Administration in Washington DC, 'but the changes we are currently witnessing can only be explained on the basis of human induced impacts'.

The fossil record shows that coral reefs have recovered from such global scale climatic events in the distant past. But this has typically taken between two and 100 million years.

Increases in sea temperature are far from the only concern. 'Newly emergent diseases are raging through the corals of the Caribbean', said Richard Aronson, Senior Marine Scientist at the Dauphin Island Sea Laboratory in Alabama. 'Most of these diseases are very difficult indeed to get a handle on, and they are starting to get a hold in the Pacific'.

Destructive fishing practices such as the use of dynamite and cyanide are even more immediate threats to reefs than climate change and disease, says Lida Pet-Soede, WWF Indonesia's Programme Manager for Fisheries. Up to 80 per cent of Indonesia's reefs have been severely degraded in this way.

Involving local communities who have a direct stake in the continuing wellbeing of their reefs is the key, says Rili Djohani of The Nature Conservancy, a US-based conservation programme that works in Indonesia. 'There are innovative and creative models for us to build on.'

But, according to Djohani, it's a race against time. 'The pressures are increasing hugely.' Regions like South East Asia, home to the richest and most diverse coral ecosystems, are also undergoing rapid economic and population growth combined with political turbulence. In most countries, conservation budgets have been cut by 80 per cent since the economic crisis of 1997/98. In Indonesia, exports of fish caught illegally, much of it from reefs in ways that cause severe degradation, are thought to be twice as large as legal exports.

Hoegh-Gulberg agreed that such direct effects from human action were an enormous threat to coral reefs, but added that this was not a good reason for ignoring the danger of climate change. 'Just because you have a rhino charging at you and it's only 20 metres away, doesn't mean you should completely ignore an angry bull elephant which is 50 metres away'.

Kirkman says the over-riding challenge is greater co-ordination. Present conservation efforts resemble 'a mob of people kicking footballs around a poorly-defined field'. Ironically, the symposium itself perhaps provided one example of this. In addition to funding by Western aid agencies, its sponsors include Southern Pacific Petroleum/Central Pacific Minerals. This Australian company is exploiting an oil shale reserve estimated to hold 29 billion barrels of oil equivalent and situated only a few yards from the edge of the Great Barrier Reef World Heritage Area. Oil shale is among the most carbon intensive of fossil fuels.

Caspar Henderson is a freelance journalist.

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