Countries of the South China Sea area have great potentials for large-scale development of commercial farming of finfish, crustaceans, molluscs and seaweeds. Estimates by country are shown in Table 10.
Existing operations use a total of about 427 000 ha: fish and shrimps (singly or combined) 416 000 ha (including fish alone 3 600 ha and shrimp alone 10 000 ha); molluscs 9 000 ha; others 2 000 ha. Of the 416 000 ha used for fish and shrimps, about 365 000 ha are milkfish ponds, most of which produce milkfish as the principal crop and shrimp as a secondary crop. Of the area used for mollusc farming, about 5 500 ha are for oysters, 3 600 ha for cockles and about 800 for mussels.
All the existing milkfish ponds can be improved to increase production of both fish and shrimps; and at least one third of them (a minimum of 100 000 ha) have the potential of being converted gradually into high production shrimp farms.
| Countries | Existing operations | Estimated potential area | ||||||
| Fish and shrimp | Cockles, mussels, oysters | Others | Total area | Fish and shrimp | Cockles, mussels, oysters | Others | Total area | |
| Indonesia | 184 000 | no record | no record | 184 000 | 890 000 | 100 000 | 10 000 | 1 000 000 |
| Khmer | no record | no record | no record | no record | 38 000 | 10 000 | 2 000 | 50 000 |
| Malaysia | 630 | 3 000 | 870 | 4 500 | 120 000 | 25 000 | 1 000 | 146 000 |
| Philippines | 171 500 | 3 500 | 500 | 175 500 | 500 000 | 40 000 | 10 000 | 550 000 |
| Singapore | 465 | no record | no record | 465 | 790 | 2 000 | 2 790 | |
| Thailand | 8 350 | 1 150 | 500 | 10 000 | 130 000 | 15 000 | 5 000 | 150 000 |
| Hong Kong | 1 000 | 2 000 | no record | 3 000 | 1 000 | 5 000 | 500 | 6 500 |
| Vietnam | 50 000 | no record | no record | 50 000 | 500 000 | 95 000 | 5 000 | 600 000 |
| Total | 415 945 | 9 650 | 1 870 | 427 465 | 2 179 790 | 292 000 | 33 500 | 2 505 290 |
The total of estuarine areas, mangrove swamps, coastal flats and shallow waters of the South China Sea region having potential for aquaculture purposes is well over 10 million ha. Not all of this should be used for aquaculture, however, since large areas should be reserved as mangrove forests for nursery grounds of fish and shrimps, and for other purposes. Thus the total area that might be available for coastal aquaculture development is estimated to be in the order of 2 500 000 ha (Table 10). This might be distributed approximately as follows:
| Fish-cum-shrimps | 1 275 000 |
| Fish alone | 300 000 |
| Shrimp alone | 600 000 |
| Molluscs | 292 000 |
| Others | 33 000 |
| 2 500 000 ha |
There are many species of animals and plants present in the waters of this region that are suitable for large-scale farming purposes because they have high food value, good flavour, high acceptability to consumers and fast growth rates. The species that are now being cultivated extensively or on pilot or experimental scales have been enumerated in Table 1. Of these the following have the best potentials for development:
Shrimps - The existence of a large local and foreign market for penaeid shrimps and the extensive potential sites for their culture make prospects for raising them very good in the area. The prawn, Macrobrachium, also has good potential, but it needs further promotion into the world market.
Finfish - The eels have a large market demand in some countries, including Japan and Germany, and rapid expansion of the culture of these fish is expected. Milkfish has a high local demand in countries which already produce it (Indonesia, the Philippines and Taiwan) but not in the other countries (Vietnam, Thailand, Malaysia and Khmer) where expansion of its culture is possible. Its use for bait in tuna longline fishing is a possibility. The raising of groupers, sea-bass, porgies, snappers - all highly priced species - will continue to develop as small local but lucrative ventures.
Molluscs - The production of most of the cultivated molluscs can easily be expanded in many countries in the area, but shortages of local or foreign markets is a constraint to further development. Research on alternative uses of these products should be done to create more demand for these useful and easily cultivable commodities.
Seaweeds - These are new as cultivated resources in this region, but growing demand is expected to expand their cultivation. In addition, natural sources of the desired species are being depleted rapidly so that the demand for cultivated products will increase.
Large areas are awaiting development of the traditional types of pond culture and considerably increased production will be attained by this expansion. Production can be increased, especially by the use of organic and inorganic fertilizers. Artificial feeding can also increase production, but this technique will not be adopted generally because of the cost. But even slight improvement of present methods, including application of fertilizers, feeding, stock manipulation, and pest and predator control, is expected to effect a hundred percent increase in the production from existing areas. Compared to the present production in coastal aquaculture farms of about 500 kg/ha/ann for fish and 350 kg/ha/ann for shrimps, yields of over 2 000 kg/ha/ann for fish and over 2 500 kg/ha/ann for shrimps have been achieved in this region and in Japan, by the application of improved cultural and management methods. A figure of 1 000 kg/ha/ann can therefore be regarded as a conservative average for fish and shrimp when the existing practices are improved. Using this same figure as the expected production from expanded coastal aquaculture operations, the total annual potential can be projected as follows:
| From existing ponds | 415 000 mt |
| From potential areas | 2 175 000 mt |
| Total | 2 590 000 mt of fish and shrimps |
Moreover, intensive culture in pens and cages is rapidly coming into general use in many places in the area, and this will continue to expand, especially after the techniques become better known. This can raise the potential even higher. So can extensive culture practices in the open areas (especially for molluscs and seaweeds) as these continue to expand to new areas further from population centres and industries. The demand for these latter commodities will determine their future.
Climatic conditions
All the countries of the South China Sea region are located within the tropical zone; they have warm climatic conditions the whole year round, without a cold winter period. Under those conditions fish and shrimps are able to grow continuously and rapidly throughout the year, and therefore the application of the highly productive modern methods of intensive coastal aquaculture is favoured. By contrast, in temperate waters there is an annual cold period of about three months, during which not only do the cultured fish and shrimps stop growing, but expensive facilities and efforts must be provided to protect them.
Employment opportunities
Coastal aquaculture operations require not only pond operators (farmers) but also seed collectors, seed producers, fish food producers, engineers, gear makers, marketing people and a large number of unskilled labourers. At present the total number of persons involved in taking care of about 400 000 ha of farms is approximately 200 000, or one person for every two hectares. Since there are about 1 600 000 ha of potential areas available for future development, even with improved technique that requires less human labour so that an average of one person for every four hectares will be needed, a total of 500 000 jobs will be created. There is an abundance of manpower available in the region, but training will be required in this specialized industry.
