coasts and oceans > features > where has all the coral gone?
Where has all the coral gone?Posted: 01 Aug 2002
by Henrylito D. Tacio
Underwater, coral reefs provide a fascinating sanctuary for a multitude of marine species, but destructive human activities are threatening this valuable resource. Nowhere is this more true than in the Philippines, as Henrylito Tacio reports.
In the Philippines, an estimated 10-15 per cent of the total fisheries come from coral reefs. About 80-90 per cent of the income of small island communities come from fisheries. "Coral reef fish yields range from 20 to 25 metric tons per square kilometre per year for healthy reefs," says Dr Angel C. Alcala, former Philippine environment secretary.
Fish and coral community on the reef wall. Batangas, Philippines
© Eric T.J.T. Kwint/ReefBase
There are three major types of coral reefs. These are the fringing type (those found n the edges of the island and which constitutes 30 per cent of the country's coral reefs); the barrier type (best exemplified by the Dajanon Reef of Central Visayas); and the atoll (of which the Tubbataha and Cagayan Reefs in the Sulu Sea are ideal examples).
The Philippines is home to over 400 local species of corals, which is more than what is found in the famous Great Barrier Reef of Australia. Unfortunately, most of these species are now gone and others are facing extinction. "Nowhere else in the world are coral reefs abused as much as the reefs in the Philippines," deplores Don E. McAllister of the Ocean Voice International.
An analysis of more than 600 data sets showed that "excellent" reefs (live hard and soft coral cover above 75 per cent) has reduced from 5.3 per cent to 4.3 per cent since the late 1970s. If hard corals alone are considered, only 1.9 per cent of the reefs can be called "excellent," with average hard coral cover on all reefs at 32.3 per cent, whereas it used to be much higher.
The decline is thought to be due primarily to destructive human activities. "Many areas are in really bad shape due largely to unwise coastal land use, deforestation and the increasing number of fishermen resorting to destructive fishing methods," says marine biologist Porfirio M. Alino of the University of the Philippines Marine Science Institute (MSI).
Destructive fishing methods - ranging from dynamite blasts to cyanide poisons - are destroying vast areas of reef. Fishermen blast reefs with dynamite to stun the fish. When fish float to the surface, fishermen scoop up large quantities at once. Heavily dynamited reefs produce only 2.7 to 5 metric tons per square kilometer per year compared to 30 metric tons for healthy reefs.
Blast fishing, Bohol, Philippines
The damage caused by dynamites to reefs goes beyond the shattering impact of the explosion itself. After a blast, algal growth quickly smothers the coral because the shoals of grazing fish that would normally keep it under control have been decimated.
Although illegal in most countries, dynamite fishing is still widely practiced in 40 countries - including the Philippines - because of economic need and poor enforcement of laws prohibiting it. In the Philippines, explosives have damaged an estimated one-sixth of reefs since 1945.
In many parts of the world, natural poisons have long been used in fishing without apparent damage. But such is not the case of sodium cyanide. In the Philippines, 80 per cent of the exotic fish destined for pet shops and aquariums throughout Europe and North America are captured using cyanide. There is also a growing demand for live fish at upscale restaurants.
"The annual trade is worth at least US$1.2 billion wholesale," says Dr Vaughan Pratt, president of the International Marinelife Alliance, a Philippine nongovernmental organization that is working to save the coral reefs of the Western Pacific.
Fishermen stun fish by squirting cyanide into the reef areas where these fish seek refuge. They then rip apart the reefs with crowbars to capture disoriented fish in the coral where they hide. In addition, cyanide kills coral polyps and the symbiotic algae and other small organisms necessary for healthy reefs.
According to the Coral Reef Alliance (CORAL), an estimated 330,000 pounds of cyanide is sprayed on Philippine coral reefs each year. "These practices are criminal," decried Jacques-Yves Cousteau, after a recent visit to Palawan to examine reefs destroyed by cyanide fishing. "They attack the natural productive environment which allows the renewal of marine resources. Destroying coral today is destroying tomorrow's fishes."
Cyanide fishing operations are moving from the over-harvested and devastated reefs of the Philippines to destroy remote and pristine coral reefs in eastern Indonesia, Papua New Guinea, Palau, Tuvalu, the Federated States of Micronesia, and other nations in the Western Pacific.
Another equally destructive fishing method is the muro-ami, which was introduced by Okinawan fishermen before World War II. The muro-ami is a drive-in net used for fishing in coral reefs. It consists of a net bag with two long wings into which the schooling fish, like the dalagang bukid, are driven by the divers. The gear utilizes vertical scarelines weighed down by stones or chain links for creating a disturbance that drives out the fish from the coral reef into the net.
While he admitted that muro-ami is an effective fishing gear, Dr Rafael D.Guerrero III of the Philippine Council for Aquatic and Marine Research and Development cited some dis-advantages. "The problems related to muro-ami fishing are its employment of minors (young boys) for fishing, their exposure to health hazards (like the "bends" or narcosis) and the destruction of coral reefs because of the weighted scarelines."
A study conducted by marine biologists Ken Carpenter and Alcala in l977 showed that 50 divers operating the gear could damage as much as l7 square meters per hectare of coral reef per operation. A muro-ami fishing boat usually operates 3-4 times in a fishing season.
In the late 1980s, muro-ami was banned in the Philippines and was replaced by the large-scale, drive-in fishing technique called pa-aling. Prior to its approval as an alternative, pa-aling was found to incur minimal physical damage to corals. Recently, the technique has been reported to be as bad as muro-ami. Despite this, the operation of pa-aling continues in reefs of the South China and the Sulu Sea and in the vicinity of Palawan.
Coral mining has also depleted the country's reefs. In fact, an estimated 1.5 million kilograms of coral are harvested annually as part of the international trade in reef products.
Boat stacked with corals presented to prospective buyer. Cebu, Philippines.
© Michael Ross/ReefBase
The Philippines, according to Panos Institute, supplies more than a third of the total, with Malaysia, Indonesia, New Caledonia and Fiji supplying another third.
"The biggest demand comes from the United States, which has banned domestic coral mining," the Panos briefing on coral reefs states. "In 1989, US also banned the import of coral from the Philippines (where its export is illegal); however, supplies continue to arrive through illicit channels, and from Indonesia and Singapore."
In recent years, the phenomenon called bleaching, as result of warming sea temperatures, has also threatened the country's sensitive coral reefs. From 1997 to 1998, massive coral bleaching - in which corals turn chalky white - was reported in Masinloc, Zambales; Bolinao, Pangasinan; Bacuit Bay, El Nido, and Coron Islands in Palawan; and Puerto Galera, Oriental Mindoro.
Also contributing to the destruction of coral reefs in the Philippines are sedimentation from erosion of soil from deforestation; the quarrying of coral reefs for construction purposes; pollution from industry, mining, and municipalities; and coastal population growth.
Deforestation adjacent to reefs increases
sedimentation. Palawan, Philippines
� Lambert A.B. Me�ez/ReefBase
"The degradation of coral reef ecosystems in the Philippines and other places in could have dire consequences," says State of the Reefs distributed during the International Coral Reef Initiative a couple of years ago. "Its destruction can greatly reduce fish production, thus endangering the fish supply in the country."
Coral reefs, after all, produce about four times more fish per unit compared to the coastal trawl fisheries, says Dr John McManus, a marine biologist and one of the contributing authors of Reefs at Risk. There are 44,000 square kilometers of coral reefs in the Philippines. Fish provides more than half of the protein requirements of Filipinos.
There's more to reefs than fish. "The extensive destruction of Philippine coral reefs has constricted the development of tourism in the country's coastal areas," contends McAllister. "If the coral reefs recover, there will enormous growth in coastal tourism. Today, with most of the coral reefs in a poor state, it is not an exaggeration to say that the country has lost one-third of its potential as a tourist spot in Asia."
According to Dr Alcala, the aesthetic quality of protected coral reefs serve to attract tourists. He cites the case of Apo Island, off the southern coast of Negros. This 100-hectare marine protected area brings in some US$126,000 annually to the 600 inhabitants of the island and to a number of boat operations on the mainland Negros. Quoting officials from the Protected Area Management Board for Apo Sanctuary, he says that tourist fees alone amount to about US$40,000 annually.
More importantly, coral reefs would be the sources of many new medicines in the 21st century. "Marine sources could be the major source of drugs for the next decade," says Dr William Fenical, a natural products chemist at the Scripps Institution of Oceanography in La Jolla, California, USA. The US National Cancer Institute (NCI) already spends one-third of its research budget to screen about 1,000 species of oceanic invertebrates and plants each year, including sea slugs, sea squirts, sponges, and several other denizens of coral gardens.
For centuries, coastal communities have used reef plants and animals for their medicinal properties. In the Philippines, for instance, giant clams are eaten as a malaria treatment. Chemicals from sea sponges collected off the coast of Florida have been used in developing a new drug, Ara-C, used to treat acute myelocytic leukemia and non-Hodgkin's lymphoma. The antiviral drug called Ara-A is used for the treatment of herpes infections.
Al Gore, when he was still the vice-president of the United States, spoke out on the issue: "To conserve these natural treasures, we must reduce human impacts on coral reefs by immediately controlling pollution, reducing overfishing, increasing protection and sustainable use of our valuable coral reef resources," he suggests.
"By working together - from local communities to regions and internationally - I believe we can, and must, reverse the tide of destruction and conserve the world's precious coral reefs."
Henrylito Tacio is a People & the Planet correspondent based in The Philippines.