Destinations » Save Coral Reefs

The alarming results of the first comprehensive global survey of coral reefs revealed that strong action must be taken to protect these precious ecosystems

For years marine scien­tists and divers have voiced concern about the damage increasingly in­flicted on the world’s coral reefs by humans, but until Reef Check 97 there had never been a comprehensive scientific study to confirm their fears.

Sadly, the study’s prelimi­nary results have revealed that -the world’s coral reefs are in much worse shape than anyone had previously believed” and that “coral reefs are being plun­dered on a global basis”. So says Gregor Hodgson, Hong Kong-based coral reef scientist and Reef Check’s global coordi­nator. Ninety-five percent of the sites surveyed across the globe had been damaged by humans. Most of this damage was due to overharvesting and destructive fishing techniques such as cyanide and dynamite fishing which have left reefs barren, and with many of the fish and shellfish that once thrived there gone forever.

Not only are coral reefs the most diverse of all marine eco­systems and a source of food for several hundred million peo­ple they also hold great po­tential for the development of drugs from genetic materials, provide important coastal protection and are a global tourist attraction for 7,000,000 sport divers each year. But for how much longer?

Marine scientists have talked for years about compiling a global survey of coral reefs arid an examination of such an important natural resource was long overdue. But the timing of the inaugural Reef Check couldn’t have been more appro­priate with 1997 being Interna­tional Year of the Reef.

Hodgson first posted some proposed Reef Check methods on the internet in October 1996, with full support from the Insti­tute for Environment and Sus­tainable Development (IESD) at the Hong Kong University of Science and Technology. Con­sequently, respected marine scientists across the world en­thusiastically offered advice and support to the project.

ISED coordinated the entire project on their Website, select­ing regional and national coor­dinators, and posting fund-rais­ing information and other useful information on the site. Many teams needed to raise large sums of money through spon­sorship to cover their travel, ho­tel and diving expenses. Finally, from June 15-August 31, 1997, over 100 marine scientists and 750 volunteers surveyed 300 reef sites across the Red Sea, the Caribbean and the Indo-Pa­cific region.

Each team surveyed a se­lected 800sqm site (larger than a football field), taking a tally of 20 “indicator species”, such as the humphead wrasse as an Indo-Pacific indicator of poison fishing, and lobster as a world­wide indicator of shellfish har­vesting pressure.

The teams also recorded other indicators of human im­pact, such as broken corals due to anchor damage, and blooms of fleshy algae indicating sew­age pollution, while transect surveys were taken along a

100m line — at 3m and 10m below the surface — to deter­mine the overall condition of the corals themselves.

According to Hodgson, the results were “shocking”. There were no lobsters — previously abundant on reefs throughout the world — at 81% of reefs sur­veyed, while there were no large grouper at 40% of the sites, with only low numbers of grouper most of the other sites.

However, more than 20 large grouper were recorded at two sites in the remote Maldive Islands and at three sites in the Red Sea where no poison or dy­namite fishing occurs an ex­cellent indication of how populations of these fish are di­rectly affected by reef damage. Most of the results for the indi­cator species followed such pat­terns, with significantly depleted levels of edible and collectible fish in unprotected areas.

What makes the findings even more shocking is that the surveys were conducted at “good” sites, i.e. reefs that were judged to be in relatively un­touched condition. This may ex­plain why the corals themselves were observed to be relatively healthy (indicated by nutrient enrichment, associated with sewage pollution), since most of the sites were not near areas where pollution is rife.

The survey’s conclusion was not only that action must be taken immediately, but also that governments must take more responsibility for the state of the world’s reefs.

“The results proved that those marine parks with proper management allow populations of indicator species to recover. We need to increase the number and size of these pro­tected areas,” says Hodgson. “It is also especially important to realize that we must tighten up on destructive fishing tech­niques, for example, encourag­ing countries to impose import bans on fish gained by unsus­tainable fishing methods!

While Hodgson admits that the surveys gave only a “snap­shot” of the world’s reefs, the evi­dence presented shows that, if the ultimate goal is the sustain­able use of marine resources, then Reef Check 97 is a crucialfoundation on which marine con­servation efforts must build.

The horrendous effects of dynamite fishing — so prevalent in Southeast Asia— has caused the complete disappearance of many species offish from coral reefs where they were once abundant

Anchor damage, as seen here in the Philippines, is a clearly visible human impact on coral reefs, but doesn’t compare with the devastation caused by dynamite and cyanide fishing.