February 14, 2002. Copyright 2001. Graphic News. All rights reserved.

Embargoed: Not for Release Until 2:00 pm U.S. ET (19:00GMT) Thursday, February 14, 2002

PICTURE CAPTION: GN13462 -- Coral reefs are rich in invertebrate life. Sponges and gorgonians (sea whips and sea fans) dominate the foreground of this view across an eastern Caribbean reef. MUST CREDIT: Photo by Callum Roberts.

PICTURE CAPTION: GN13463 -- A school of damselfish and basslets hover above the edge of a Red Sea coral reef, feeding on plankton washed in from the open sea. MUST CREDIT: Photo by Alec Dawson Shepherd.
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Marine conservation hotspots under threat

LONDON, February 14, Graphic News: Worldwide damage to coral reefs from human activities and climate warming is threatening thousands of animal and plant species, according to new research published in the February 15 issue of the journal, Science.

Researchers at Harvard University have pinpointed 18 critical places world-wide, where conservation resources would likely do the most good to save marine ecosystems.

ÒAgriculture, deforestation, and development are introducing large quantities of sediment, nutrients and pollutants into coastal waters,Ó said Callum M. Roberts, who led the research.

ÒCoral reefs are often over-fished intensively,Ó said Roberts, Òand in regions of the Indian and Pacific Oceans, fishing with dynamite and poisons has devastated reef habitats.Ó

Topping the list of 18 zones are 10 conservation Òhotspots,Ó which -- although covering only 0.03 percent of the worldÕs oceans -- affect more than one-third of all coral reefs, and may shelter more than two-thirds of all vulnerable, marine creatures.

Roberts and colleagues at HarvardÕs Department of Organismic and Evolutionary Biology studied the ranges of 3,235 types of fish, coral, snails and lobsters and compared patterns of species richness and rarity with a map of the worldÕs most threatened coral reefs. 

ÒWe mapped the geographical ranges of 1,700 species of reef fish, 804 species of coral, 662 species of snail, and 69 species of lobster,Ó said Roberts. These taxa, or groups, were studied because extensive data are available globally. The species richness of each taxa peaks in the so-called Òcoral triangeÓ of Southeast Asia, then falls off rapidly moving east across the Pacific, and less rapidly moving west across the Indian ocean. In the tropical Atlantic, all taxa are richest in the Caribbean.

The scientists identified places with the greatest number of unique species, since range-restricted creatures tend to be most vulnerable. Alarmingly, they found that more than half of all lobster species in question were confined to narrow geographic regions, while nearly a third of snails, and more than one-fourth of fish were also range-restricted. 

The threat levels associated with each of the 18 locations were classified on a range of one to three: low, medium or high

The ten highest threat ÒhotspotsÓ include: The Philippines; Gulf of Guinea; Sunda Islands; Mascarene Islands; Eastern South Africa; North Indian Ocean; South Japan; Cape Verde Islands; West Caribbean; and Red Sea. 

Eight other places falling between threat level one and two include: New Caledonia; Great Barrier Reef; Gulf of California; Hawaii; Western Australia; Easter Island; St. Helena and Ascension Islands; and Lord Howe Island.

Of the 18 locations examined, 14 were adjacent to terrestrial biodiversity Òhotspots,Ó where forest loss, expanded agriculture and construction were seen as threatening the environment. 

Corals first appeared about 475 million years ago as a result of the association of jellyfish-like animals and single-celled plants within the same compound organism known as polyps.

Billions of polyps, which resemble tiny anemones, are connected by bridges of tissue in order to share food and react to stimuli. Polyps extract salts from sea water to build cup-shaped calcium carbonate shells around their bodies, but polyps are slow builders -- AustraliaÕs Great Barrier Reef first began to develop some 25 million years ago. Most corals need constant temperature, and clear water so that sunlight can reach them.

In an earlier study of Caribbean fishing zones and marine reserves by Roberts and colleagues, they found that marine conservation of coral reefs and sedentary fish that inhabit them resulted in large increases of catches in adjacent fishing grounds.

Roberts concludes that extending terrestrial conservation efforts seawards could help protect these fragile marine ecosystems, otherwise human actions may alter, perhaps irrevocably, life in the sea.
/ENDS
Source: Science