Regional Perspectives:

East Asian Seas

Map 4. East Asian Seas


click on map for larger (~800K) version

The region (Map 4) is unique in its abundance and variety of reefs and for the fact that it is at the center of coral reef ecosystem biodiversity. Mangrove is the dominant coastal community (at its diversity peak); it supports over 100 seabird species, and provides breeding and nursery areas for fish and shrimp . The most diverse seagrass flora -- about 20 species -- in the world is also found in the region. Economically and environmentally important, seagrasses form dense beds, cover large coastal areas, provide habitat and nursery areas, and are sources of food for many organisms (GBRMPA et al., in press). They also support millions of coastal villagers who rely on them for a wide variety of useful products. Over 30 percent of the world's coral reefs are found in southeast Asia alone. Rapid economic and human population growth -- over 440 million for peninsular and insular southeast Asia, with the population doubling in the next 25-35 years -- and severe local coral reef ecosystem degradation also characterize the region. Coral reef ecosystems in more remote areas are probably in better condition. People extract about 60 percent of the regions' animal protein from the sea. Major stresses include: organic and inorganic pollution, sedimentation, and overexploitation. For these reasons it is estimated that most of the reefs will be severely depleted within the next 40 years (Wilkinson et al., 1993).

In Southeast Asia (SEA), Vietnam has over 200,000 ha of mangrove and cover has decreased about 45 percent since 1945. Brunei has about 7,000 ha and Cambodia about 10,000 ha (GBRMPA et al., in press). Few reefs exist off Brunei Darus-salam, Cambodia, and Vietnam because of high coastal turbidity. Few of the offshore reefs have been studied. Reefs off Brunei are rich in coral and fish species as fishing pressure is low. The best Burmese reefs occur near the Thailand border where river effects are low. Reefs of the Mergui Archipelago are in good shape, although many of the larger reef animals (turtles) are exploited. Reefs off Vietnam have been damaged extensively by sedimentation, as well as by blast and cyanide fishing (Wilkinson et al., 1993).

Indonesia, with it's 81,000 km of coastline and over 17,000 islands, is of critical importance as the center of coral reef ecosystem diversity (Wells, 1993). It has a large amount of mangroves (4.25 million ha) and those in the western part of the country have suffered from illegal cutting, coastal development (about 300,000 ha lost) and land-based pollution. Over 1 million hectares have been designated for use as "production" forest. Mangroves in the east are less impacted. Coral reefs in Indonesia are extensive and represent the most significant reef resource in southeast Asia. Reef conditions vary. Off Java and Sumatra, reefs are damaged from overexploitation, sedimentation, and organic pollution. To the far east and northeast, reef ecosystems are in excellent shape -- particularly those which are relatively inaccessible to coastal dwellers. In central Indonesia, reefs are degraded from blast fishing, cyanide fishing, and overfishing/collecting. Population pressures are lower on eastern Indonesian reefs and, if destructive fishing is controlled, many damaged reefs in this area may recover. Human population growth and associated forest clearing and sedimentation are expected to severely affect reef health in western Indonesia. Coral reef ecosystems of Palau Seribu, which provide fishery resources for Jakarta and tourist opportunities, are being severely impacted by mainland pollution and overfishing (Wilkinson et al., 1993).

Malaysia has 650,000 ha of mangroves. Coral reefs of Malaysia suffer from organic and sediment pollution and overexploitation, but not as much as in other regional countries. Construction related sedimentation has impacted the reefs in the Palau Redang marine reserve. All reefs in the Peninsula Malaysia region are expected to decline significantly in the next 20 years as a result of sedimentation and water pollution. Reefs off Sabah are experiencing overexploitation (Wilkinson et al., 1993).

Over 80 percent of the mangroves in the Philippines have been lost since the 1920s, leaving only about 100,000 ha -- half of which consists of secondary growth. The largest and most pristine stands are off Palawan and Mindanao Islands. Reefs are in decline throughout the Philippine Archipelago due to blast and cyanide fishing, muro ami fishing (involving the use of weights on ropes to smash corals and drive fish into nets), sedimentation, port construction and eutrophication. Coral cover is rapidly declining, and fish populations are low from overfishing. The loss of 80 percent of the mangrove area and more than half of the total forest area since 1920 has stressed reefs with sedimentation and caused fish populations to decline. Large areas of Scarborough reef off Luzon and other large, offshore reefs has been denuded of fish and coral from blast and muro ami fishing within the last two years (Wilkinson et al., 1993). Between 1966 and 1986 the productivity of coral reefs in the Philippines dropped by one-third as the national population doubled (McAllister, 1988). The Philippines is the major exporter of coral for displays and aquariums, despite being prohibited within the country and by the states where tourists import them. Giant clams have recently been added to the list of species covered by the Convention on International Trade in Endangered Species (CITES) as a means of reducing the trade.

The coral reefs of Singapore are valuable ecotourist destinations, however they are being severely degraded by construction of port and oil processing facilities and other coastal development. Coral cover is high on the outer reefs and reduced (<50 percent) on nearshore reefs. Heavy sediment loads limit coral distribution to < 10 m depth. Fish and coral collecting for the aquarium trade are also threats (Wilkinson et al., 1993).

From 1979-87, mangrove cover has been reduced by 25 percent in Thailand and the remaining 196,000 ha (Aksornkoae, 1993) are under stress from farming, mining, salt farming, and coastal construction. Thailand's nearshore reefs are suffering from coastal development while offshore reefs have relatively high coral cover. Domestic and industrial pollution from Bangkok and Pattaya have almost totally destroyed the reefs in the northern Gulf of Thailand. Reefs off the western coast of the Gulf are in better shape with coral cover often exceeding 50 percent. However, recent reports show that coral cover is declining by 20 percent annually due to tourist-related coastal clearing and sewage pollution. Healthy reefs with over 75 percent coral cover can be found in the Andaman Sea off Smilan and Surin Islands. Off Puket, reefs are being stressed by overfishing, tourist activities and the release of sewage and sediment into shallow Phangnga Bay. The Gulf of Thailand fishery is close to collapse (Wilkinson et al., 1993).

Off China, mangroves are threatened by agricultural land reclamation, construction of dikes for aquaculture and by firewood cutting. Coral communities are found mainly around offshore islands and archipelagos in the Nan Hai. The most important reef areas are south of Hainan where reefs suffer from overfishing and siltation. Coral mining, dredging, and collecting for the aquarium trade also impact reefs (IUCN/UNEP, 1988).

Off Hong Kong, there are no true reefs, however, about 49 species of corals grow on hard bottom along the eastern and southeastern coasts and in certain ocean areas. Coral growth in central Hong Kong is impossible because of urban, industrial, and agricultural pollution, while land reclamation, overfishing/collecting, and visitor use threatens corals and mangroves in the northeast. Reefs in the east suffer from land reclamation, dumping of dredged materials, and sewage discharge (IUCN/UNEP, 1988).

Except for the sandy west coast, coral reef ecosystems are found all around Taiwan and have magnificent soft coral coverage. Tourist abuse, aquarium fish collecting, sedimentation from construction and dredging, explosive fishing, coral collecting, and various types of pollution threaten many reefs (IUCN/UNEP, 1988). Taiwanese harvesting of giant clams has led to local extinctions.

Off the many islands of Japan, coral-eating crown-of-thorns starfish (Acanthaster) infestations and coral bleaching have affected some reefs. Deforestation, agricultural development, dredging, coastal construction, tourism, and reef gleaning are growing threats. In Okinawa, sedimentation from coastal construction and agriculture has dramatically decreased coral cover (IUCN/UNEP, 1988).

Human Consequences

Coral reef ecosystem degradation would significantly limit food supplies to growing populations and would devastate commercial fishing and tourist industries.

Existing Management and Research Programs

Many SEA countries have created strong legislation to protect coral reefs and designated marine parks but funding and resources are not available for effective management (Wilkinson et al., 1993). Information on reef health is variable. Reconnaissance surveys have been conducted for about half of the nearshore reefs off Taiwan, the Philippines, and Thailand. In areas such as Indonesia, only 10 percent of the reefs have been studied by scientists (Ginsburg, 1994).

The Government of Indonesia is increasing efforts to manage large reef tracts, but resources are limited to enforce regulations. In the Philippines, resources are in sufficient to effectively manage and protect marine resources. The substantial national debt burden, which generates annual payments equal to 40 percent of the GNP, and rapidly increasing population further exacerbate the problem. Local area management plans are helping to protect Philippine coastal resources. The National Parks Board of Singapore plans to establish several marine parks. In Thailand, a coastal resources management program was established in 1986 with U.S. Agency for International Development (USAID) assistance. The royal family is working with local residents to protect marine resources, there has been a ban on further prawn pond construction and mangrove destruction, and US $32 million has been allocated for mangrove and coral reef management over the next few years (Wilkinson et al., 1993). Marine research off China has been carried out for years on Hainan by the South China Sea Institute of Oceanography. The Tuntze Nature Reserve exists on the north coast of Hainan and several other reserves have been proposed. There are several marine parks off Hong Kong. There are over 50 marine parks in Japanese waters and several marine science institutes with long-standing programs. Taiwan has a Coastal Area Environment Protection Plan, the Taiwan Nature Conservation Strategy, several marine parks and over 20 fishery conservation zones that act as nursery areas (IUCN/UNEP, 1988).

Several national institutions in the region have achieved international prominence. Most notable of these is the Marine Science Institute of the University of the Philippines, which conducts a variety of projects on coral reef science and management. Silliman University in the central Philippines has a long history of coral reef research including pioneering work in mariculture and in the development of village-based coral reef reserves. These two institutions combined forces in the mid-1970s to conduct a national survey of coral reefs of a scope unmatched to the present by any nation except Australia. Other regional centers of coral reef research include Thailand's research facilities in Phuket and the coral reef research group of the University of Singapore. The latter has recently been involved with others in a program to move a complete coral community out of the path of a construction project and into a safe area. Malaysia, Indonesia, and Brunei all have coral reef research groups which are growing in prominence. Recently, Vietnam has initiated a variety of reef survey programs. Various institutions in China have conducted research on coral reefs over the last two decades, although much of this material has been of limited access outside the county until recently. In addition to the national institutions, the region has benefited by the fact that the globally focused International Center for Living Aquatic Resources Management (ICLARM) has been based in Manila since 1977. This institution has collaborated in a variety of coral reef studies, and has provided analytical methodology and training to boost efforts in this region and others.

Research on coral reefs, mangroves, and sea-grass beds was considerably enhanced through the implementation of the ASEAN-Australian and ASEAN-U.S. environmental programs, and the Fisheries Stock Assessment Collaborative Research Support Program of USAID in the mid- to late-1980s. The first two programs involved researchers across the region in coordinated training, method development and field research; and the latter focused on development of methods and analytical approaches, and on providing training. The combination of these programs resulted in a large group of well-trained researchers with modest funds for regionally standardized fieldwork, who produced and are still producing substantial material on the ecology and management of shallow-water marine ecosystems.

Preliminary Recommendations for Regional Action

In addition to the general global recommendations, we suggest the following:

Integrated Coastal Zone Management

  • Intensify community development activities in coastal areas to provide alternative livelihoods and enhance village-level resource management;
  • Produce local integrated coastal zone management plans and marine parks;
  • Provide effective management to existing "paper parks";
  • Eliminate the use of damaging fishing methods;
  • Diversify the fishery and use less exploited species; and
  • Strictly regulate and enforce the taking of corals, shells and fish for the aquarium/curio trade.

Capacity Building

  • Provide village-level public education on sustainable use practices; and
  • Train personnel to plan and implement research and conservation programs.

Improved Scientific Understanding of Coral Reef Ecosystems

  • Encourage more coral reef research in the region;
  • Publish research results more widely.


State of the Reefs * May 1995

Back to Indian Ocean

On to Pacific

Return to Table of Contents