State of fisheries: Fish production in jeopardy due to coral reef destruction
Text and Photos by Henrylito D. Tacio
(Last of Three Parts)
The Philippines is part of the Coral Triangle, the epicenter for marine biodiversity and what is considered the Amazon of the Sea. The Coral Triangle is “an area with more species of fish and corals than any other marine environment on earth,” says the Unico Conservation Foundation.
The Coral Triangle – so named because of its distinct triangular shape – spans 648 million hectares off the coasts of Indonesia, Malaysia, Papua New Guinea, the Philippines, Solomon Islands, and Timor-Leste. Among these countries, the Philippines is considered the world’s “center of marine biodiversity,” according to the World Bank, “because of its vast species of marine and coastal resources.”
The country’s coral reef area is considered the second largest in Southeast Asia – after Indonesia. Estimated at 26,000 square kilometers, it holds an extraordinary diversity of species. So far, scientists have identified 915 reef fish species and more than 400 Scleractinian coral species, 12 of which are endemic, the BFAR reports.
On the verge of extinction
Unfortunately, the beautiful coral reefs are on the verge of extinction. The Inventory of the Coral Resources of the Philippines in the 1970s found only about 5% of the reefs to be in excellent condition, with over 75% coral cover (both hard and soft).
Another study conducted in 1997 showed only 4% of reefs in excellent condition (75% hard or soft coral cover), 28 % in good condition (50%-75% coral cover), 42% in fair condition (25%-50% coral cover), and 27% in poor condition (less than 25% coral cover).
In a written report by Dr. Thomas J. Goreau after he and his team assessed the coral reefs in and around the Tubalan Cove of Malita in Davao Occidental some years back, it was observed that “large areas were found with very high live coral cover, up to nearly 100% in places, but live coral coverage would have been much higher had there not been heavy dynamite fishing damage in many areas in the past.
“Fish populations were very poor except around promontories with higher water flow,” wrote Dr. Goreau, the president of the Global Coral Reef Alliance, a non-profit international organization founded in 1994 working exclusively to save coral reefs. “The area has a mix of prime dive sites suitable for ecotourism, as well as extensively damaged areas badly in need of restoration as fisheries habitat.”
But what really caught the attention of the group was the discovery of seeing almost the entire sea bed within the cove to be almost covered with only one species of ecologically fragile cabbage corals.
“This is unique,” British diver Andrew MacDonald and his wife Jane Widdison commented. “We have only seen one species dominate an individual offshore reef before but have never seen any other ancient coral colonies like this which cover such a large area. It appears that this colony covers an area of several hundred hectares and it is likely that these corals have taken centuries to form like this.”
“Nowhere else in the world are coral reefs abused as much as the reefs in the Philippines,” deplored Don E. McAllister, who once studied the cost of coral reef destruction in the country.
Some causes
In its website, the BFAR singled out destructive fishing techniques as among the largest contributors to reef degradation.
“Muro-ami, a technique that involved sending a line of divers to depths of 10-30 meters with metal weights to knock on corals in order to drive fish out and into waiting nets was extremely damaging to reefs, leading to its ban in 1986,” the BFAR reported.
But that’s just one. “Rampant blast fishing and sedimentation from land-based sources have destroyed 70% of fisheries within 15 square kilometers of the shore in the Philippines, which were some of the most productive habitats in the world,” the BFAR noted.
Cyanide fishing, employed since 1962 to collect aquarium fish, is another destructive fishing method. “Using cyanide tablets obtained from drugstores, collectors squirt the cyanide-laced water solution from plastic bottles on coral formations where marine fishes abound,” explains Dr. Rafael D. Guerrero, a national scientist with the National Academy of Science and Technology.
Despite several attempts to stop these destructive fishing methods – through increased enforcement, larger penalties, and educational campaigns – they persevere. “Many fishers have brought destructive practices to new areas,” the BFAR said. “Many operations have shifted to more remote, pristine areas such as the Palawan group of islands, the Sulu archipelago, parts of the Visayas, and western Mindanao.”
Coastal development, farming, aquaculture, and land-cover change have also threatened the country’s coral reef ecosystem. “Over 80% of original tropical forests and mangroves have been cleared, increasing sediment outflow onto reefs,” the BFAR said. “Mangroves continue to be cut and the areas converted to fishponds, a change that allows more nutrients and sediment to reach reefs.”
Aside from human activities, natural causes of destruction among coral reefs also occur. These include extremely low tide, high temperature of surface water, predation, and the mechanical action of currents and waves.
Extremely low tides usually expose corals to sunlight and to freshwater runoff, both of which, according to marine scientists, are lethal for coral reefs if they are exposed for several hours.
High temperature of surface water is exacerbated by abnormally low tides which leave shallow reefs exposed to sunlight, rainfall, and freshwater flowing. These environmental disturbances, experts claim, cause reefs to lose 70 percent to 90 percent of their living coral cover to depths of 15-18 meters.
In recent years, corals are exhibiting a new kind of degradation: massive bleaching.
“The first ever mass-bleaching event occurred in 1998-99,” the BFAR reported. “It began at Batangas in June 1998 and then proceeded nearly clockwise around the country, correlating with anomalous sea-surface temperatures. Most reefs of northern Luzon, west Palawan, the Visayas, and parts of Mindanao were affected.”
In terms of productivity, good coral reef areas can produce as much as 30 tons of fishery products per square kilometer in a year, according to the late Dr. Angel C. Alcala, a marine scientist who was a recipient of the Ramon Magsaysay in 1992 for his pioneering efforts in restoring and conserving the coral reefs in the country.
Dwindling fish catch
The destruction of coral reefs has affected the country’s fishery resources. Unless something is done soon, fish production may soon collapse. Dr. Salome Bulayog, who was once an associate professor of the department of economics at the Visayas State University, said the aquatic marine resources of Sogod Bay in Southern Leyte have been deteriorating in recent years.
Home to a variety of fishes, Sogod Bay is a major fishing ground for the 11 municipalities that surround it. Mangko or frigate tuna (scientific name: Euthynnus affinis) is its major fishery resource. Seasonal influx of this shallow-water tuna species has provided food and livelihood to the people of Sogod and nearby municipalities.
“Frigate tuna used to abound in Sogod Bay and was a major source of income in the 70’s until the 90’s,” said Dr. Bulayog, who headed the study. “But today, fishermen could hardly catch fish.”
“Likewise, reef species population is also dwindling,” added the study. “Fishermen have to spend longer to catch a kilogram of fish; some even have to be farther from the shore.”
This is bad news for Filipinos. Fish, after all, is the second staple food of Filipinos next to rice. On average, every Filipino consumes about 98.6 grams of fish and fish products, according to the Food and Nutrition Research Institute of the Department of Science and Technology.
“Coral reef fisheries provide livelihood for more than a million small-scale fishers who contribute almost US$1 billion annually to the country’s economy,” reports Dr. Alan T. White, author of Philippine Coral Reefs: A Natural History Guide.
In addition, coastal tourism brings substantial economic benefits to the country as it is a source of foreign exchange. The Manila-based Asian Development Bank (ADB) reported that in the mid-2000s, tourism generated $16.3 billion, accounting for 9.1 percent of gross domestic product.
Major types of coral reefs
There are three major types of coral reefs, according to Dr. Alcala. These are fringing type (those found on the edges of islands and which constitutes 30 percent 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 Reef in the Sulu Sea are ideal examples).
Most of the corals in the country are found in the Palawan group of islands, which includes the Kalayaan Islands group, accounting for 41.5 percent according to State of the Coral Triangle: Philippines, published by ADB. The corresponding percentage share for the Visayas region is 29.1 percent that for Mindanao is 18.1 percent and for Luzon and Mindoro, 11.3 percent.
The corals most Filipinos know are actually the dried and bleached skeletons of soft-bodied animals that live in the warm, sunlit waters of tropical seas and look more like plants and rocks than animals.
The main part of the real coral is the polyp – an extraordinary flower-like animal with a tube-like body and finger-like tentacles. “Coral polyps get nutrition in two ways,” explains Lindsay Bennett, author of globetrotter island guide, Philippines. “They catch their food by means of stinging tentacles that paralyze any suitable prey – microscopic creatures called zooplankton – and also engage in a symbiotic relationship with zooxanthellae that live within the polyp structure.”
Coral polyps reproduce in two ways: asexually (by the division of existing individual polyps) and asexually (by combining egg and sperm from two different polyps). “This results in a free-swimming polyp that will be carried by ocean currents to find a new colony and commence a new reef,” Bennet writes.
Coral reefs are among the natural resources of the Philippines and they must be protected and conserved. The only way to save coral reefs from extinction and restore their productivity is to limit access to them.
“This is no mean task,” said the late Edgardo D. Gomez, a national scientist who was the founding director of the Marine Science Institute at the University of the Philippines Diliman. “But it seems it is the only means we can save our coral reefs from disappearing in this part of the world.”
