Press releases

Thursday 19 Oct 2006

Curbing Coastal Pollution Aids Recovery of Heat-Stressed Corals

Beijing/Nairobi, 19 October 2006 - The ability of coral reefs to survive in a globally-warming world may crucially depend on the levels of pollution to which they are exposed, new findings indicate.
Ecosystems Likely to Cope Better with Climate Change in Less Contaminated World

Global Programme Action Global (GPA) for the Protection of the Marine Environment from Land-Based Sources 2 nd Intergovernmental Review

Beijing/Nairobi, 19 October 2006 - The ability of coral reefs to survive in a globally-warming world may crucially depend on the levels of pollution to which they are exposed, new findings indicate.

Scientists studying reefs that were bleached in the late 1990s by high surface sea temperatures have found a link between recovery rates and the levels of contamination entering coastal waters from developments on the land.

The findings, released at an international marine pollution conference taking place in Beijing, China, have come from a team led by the United Nations Environment Programme (UNEP), Nature Seychelles—the environment wing of the Government of the Seychelles—and scientific and government experts from the Netherlands and Norway.

Monitoring of corals around the main Seychelles island of Mahé has found that recovery rates are varying between five to 70 per cent.

Coral reefs recovering faster are generally those living in Marine Protected Areas and coastal waters where the levels of pollution, dredging and other kinds of human-induced disturbance are considered low.

The findings are given even more urgency as a result of new modeling. It indicates that up to 90 per cent of the tropical coasts of the world may have been developed by 2030.

Achim Steiner, UN Under-Secretary-General and UNEP Executive Director, said: “The world-wide bleaching of tropical corals in the late 1990s was a taste of the likely impacts to come as a result of increases in greenhouse gases. The new studies indicate that healthy ecosystems exposed to minimal contamination are likely to recover and survive better than those stressed by pollution, dredging and other human-made impacts”.

“The world-wide effort to reduce pollution to the marine environment from land-based sources is the Global Programme of Action (GPA) whose second Intergovernmental Review (IGR2) is being held here in China. Some successes are being scored but in other areas-- like sewage; nutrients from fertilizer run off, animal wastes and atmospheric pollution; sediment mobilization and marine litter-- the problems are intensifying,” he added.

“There are numerous compelling reasons for combating pollution to the marine environment. These range from public health concerns to the economic damage such pollution can cause to tourism and fisheries. Climate change, and the need to build resilience into habitats and ecosystems so that they can cope with the anticipated increase in temperatures likely to come, now represents a further urgent reason to act,” added Mr Steiner.

His remarks came during the ministerial part of the IGR2 where delegates from some 115 countries and ministers from some 50 countries are taking part.

They also come just over two weeks before the opening of the global warming talks under the UN Framework Convention on Climate Change scheduled to open in Nairobi, Kenya, 6 November.

Key Findings from the New Report Highlighting Corals

The new rapid report on coral reefs—“Our Precious Coasts: Marine Pollution, Climate Change and Resilience of Coastal Ecosystems”—is based on surveys of coastal vegetation carried out in 2004.

These have been supplemented by 120 dives at 22 sites in 2006 alongside an overview of threats to coral reefs from pollution and coastal development worldwide.

The work was undertaken in the wake of the damage caused to coral reefs world-wide in 1997-1998 when surface sea temperatures reached up to 34 degrees Celsius.

Corals in an estimated 16 per cent of the world’s coral reefs suffered up to 90 per cent mortality as a result of mass bleaching according to another new publication to be launched at the 3 rd International Tropical Marine Ecosystem Managers Symposium, 16-20 October in Cozumel, Mexico”. See notes to editors).

Coral reefs across the Indian Ocean including around the Comoros, La Reunion, Madagascar, Mauritius and the Seychelles, were among those that were severely damaged.

Coral losses of 50 per cent to 95 per cent were recorded including in several marine protected areas. In St Anne Marine Protected Area (MPA) and Bay Ternay, located in coastal waters around Mahe, Seychelles, more than 95 per cent of the hard corals like Acropora were dead by 1999.

However, surveys in following years have found that soft coral cover including species and stony corals like Porites have increased rapidly in the Bay Ternay which is the MPA least affected by coastal development. Coral cover of soft corals has nearly doubled annually reaching 20 per cent by 2002.

The 2006 dives have confirmed the link between cleaner, less disturbed, coastal waters and continued coral recovery and recolonisation.

Christian Nellemann, senior officer of the response team, UNEP GRID-Arendal, Norway, said: “Many dead reefs were overgrown with algae and higher nutrient contents near developed areas including surface run-off of silt which apparently reduced re-colonization rates substantially”.

“We were well aware of the fact that land reclamation and coastal development could damage reefs in most tropical waters. What is really concerning is the fact that coastal pollution effectively may reduce the ability of reefs to recover,” he added.

Across Asia, mangroves are being removed at alarming rates to generate room for hotels and coastal development. At the same time the Indo-Pacific holds near 92 per cent of the world’s coral reefs, the rest mainly in the Caribbean and West Asia sites like the Persian Gulf.

Satellite images in the report reveal that over the last 30 years, coastal development of roads, settlements and resorts have developed dramatically, reducing coastal vegetation, discharging increased levels of sewage into the coastal areas and impacting the ecosystems upon which millions, if not billions, depend for food, materials and livelihoods

In Asia and Eastern Africa, up to 90 per cent of the sewage is discharged directly into rivers and the sea. While coral reefs may tolerate a little pollution, they have great problems recovering from bleaching events in polluted waters, as dead coral reefs easily are eroded by waves or get covered in algae, that thrive from the nutrients in sewage.

“Corals are sensitive; they may react to just a few percent of what we consider unhealthy nutrients in water. Even in seemingly “clear” waters, the nutrient loads can be too high for corals to recover”, says the report.

There is also concern that while coral reefs may change with climate stress, they can actually die entirely with the combined actions of pollution, sediments and overfishing.

The conditions under which coral reefs have flourished in the past half-million years are dramatically changing, says the report. Coral reefs have a natural resilience to changing environments and ability to recover, and currently some 23 per cent of the reefs are protected in some way.

“However, if we fail to protect the coastlines from unchecked piecemeal development, or protect the water sheds from deforestation, huge amounts of sewage and sediment loads will reduce the ability of reefs to recover dramatically. Once they are overgrown, it is difficult for them to recover, and over time they change or even die entirely”, says Nellemann.

“In the Seychelles, Acropora corals seemed to have survived mainly in sites with either cooler water, more current and in sites less exposed to development and pollution on the East Coast. The results confirm findings and claims world-wide that land-based pollution, reclamation, clearing of coastal vegetation and poor sewage control can damage reefs,” says the report.

“More importantly, they demonstrate that protection of coastal land areas around marine protected areas is essential for reducing local pollution and facilitating re-colonization of corals,” says the report.

Coral reefs support over one million plant and animal species and are perhaps among the most diverse ecosystems in the world, sometime called the “rainforests of the Sea”.

Coral reefs are critical to much of the coastal fisheries and are vital to tourism and snorkellers all across the tropical seas. Their annual value is projected at more than US$30 billion.

The report further projects that currently near 70 per cent of the tropical coasts are developed.

This figure may rise to more than 90 per cent in less than 25 years at current rates of development, according to the GLOBIO-model, a model designed by UNEP and research institutions to project future losses of biodiversity at a global scale from pollution, land use and development of infrastructure.

The report was prepared by a Rapid Response Team at UNEP GRID Arendal and UNEP World Conservation Monitoring Centre as a broad collaborative effort across various UNEP programmes and activities with contributors from regional UNEP, Offices, GRID Sioux Falls, GPA, Nature Seychelles, Norwegian Institute of Nature Research, and the University of Life Sciences in Norway.

Notes to Editors

Our Precious Coasts was prepared by a Rapid Response Team at UNEP GRID Arendal and UNEP World Conservation Monitoring Centre as a broad collaborative effort across various UNEP programmes and activities with contributors from regional UNEP Offices, GRID Sioux Falls, GPA, Nature Seychelles, Norwegian Institute of Nature Research and, University of Life Sciences in Norway.

It is available at www.unep.org and www.grida.no and www.globio.info together with graphics and maps.

For press ready pdfs go to (76 MB):

http://www.grida.no/climate/coastal/printfile/vitalcoastreport.pdf

A pdf optimized for screen display (meaning low resolution) can be found here (8 MB):

http://www.grida.no/climate/coastal/screenfile/vitalcoastreport_lr.pdf

The graphics used in the report are available as well (11 MB zip-archive):

http://www.grida.no/climate/coastal/graphics/Curbing_Coastal_Pollution_Graphics.zip

“Marshall, P and H. Schuttenberg (2006) A reef manager’s guide to coral bleaching. Great Barrier Reef Marine Park.163 pp): “in 1997-1998 alone mass bleaching is estimated to have caused over 90% of coral mortality to 16% of the world’s coral reefs” (publication is being launched at the 3 rd International Tropical Marine Ecosystem Managers Symposium, 16-20 th Oct in Cozumel, Mexico”

Second Intergovernmental Review Meeting of the GPA (IGR-2)

16 - 20 October 2006, Beijing http://www.gpa.unep.org/bin/php/igr/igr2/home.php

For More Information Please Contact Nick Nuttall, UNEP Spokesperson, Office of the Executive Director, on Tel: 254 20 7623084, Mobile: 254 (0) 733 632755, or when traveling 41 79 596 57 37, e-mail: nick.nuttall@unep.org

Elisabeth Waechter, UNEP Associate Media Officer, on Tel: 254 20 7623088, Mobile: 254 720 173968, e-mail: elisabeth.waechter@unep.org

UNEP News Release 2006-48

Thursday 19 Oct 2006
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