10. MOLLUSCS FARMING DEVELOPMENT PLANS IN OTHER ASEAN COUNTRIES

10.1 Indonesia

The government of Indonesia, through the UNDP-assisted Seafarming Project, INS/81/008, has already identified potential areas for oyster and mussel culture sites as shown in Tables 10 and 11.

Mussel culture is still at a very experimental stage in Indonesia. On the other hand, oysters are cultured by stake method at a very limited scale.

Mollusc production of Indonesia is mainly from wild harvesting from natural grounds. The blood cockles (Anadara granosa) is the most important species produced. Cockle farming is used to be practiced by local fishermen in West Java. However, due to lack of seeds, this was no longer practiced since 1975 (Mintardjo, 1988).

In an effort to provide coastal fishermen with alternative fishery-related occupations and improve their levels of living, the government puts high priority to seafarming development. For this purpose, Presidential Decree No. 25 was proclaimed on 25 May 1982 (Appendix 3) which was followed by a Ministerial Decree No. 473, issued 8 July 1982. One of the seafarming activities to be developed is oyster and mussel farming.

Table 11. Potential areas for oyster culture

¹Pagcatipunan, et. al., 1982
²Estimated from actual site
³Estimated from topography map
From: Mintardjo, Kisto, 1988

The guidelines for the implementation of the Decree has been prepared. The regulatory measures and control for the development of seafarming is embodied in the Seafarming Act which has been drafted for the approval of Parliament (Tiensongrusmee and Soehardi, 1988).

10.2 Thailand

Among the molluscs, the green mussel (Perna viridis) is the most important. It comprises over 50 percent of total mollusc production of Thailand. The method used is by stake method and “fish trap”. The latter is actually mussels produced from the wings of fish traps. The fish trap operators either sell or lease mussel production “rights” to mussel collectors. In other cases, the fish trap operator sets the stakes and sell the harvest rights to mussel collectors (ICLARM Tech. Rep. 19).

The total production of mussels in Thailand for the period 1982–1983 is summarized in Table 12.

Mussels and oysters are both produced in the southern part of Thailand (Figure 23). There are 7 046 ha of existing oyster farms using various culture methods such as the rock culture; culture on cement poles, cement pipes or wooden poles; tray culture and the suspension or hanging method. All these methods are practiced in shallow tidal areas except the suspension or hanging, method adapting the raft method of Korea and Japan. This latter technique is still in experimental stage.

Figure 23. Location of mussel and oyster farms in Thailand
(ICLARM Tech. Rep. 19)

Table 12. Production in tonnes and value in thousands of baht of green mussels from stake, fish traps and natural areas by province, Thailand, 1982–1983

Source: ICLARM Tech. Report 19

Research on hatchery techniques for bivalve molluscs were conducted. Initial findings showed that hatchery production of large oyster spat has a good possibility in Thailand. Further studies are being under-taken at the Brackishwater Fisheries Station at Phrachuap Kiri Khan.

10.3 Malaysia

Molluscs production constitutes about 11 percent of the total fisheries production of Malaysia. Cockle is the most important species produced. Extensive cockle farming operations started in Perak which developed as the most organized culture system in Peninsular Malaysia.

There is no organized oyster and mussel farming in the country until recently. Experimental raft cultures of flat oysters are being continued at Pulau Langkawi, Kedah; in Sabah, experimental culture of Crassostrea belcheri and Saccrostrea cucullata are also in progress. Mussel culture was successfully demonstrated in Johore Strait.

Oyster and mussel spatfalls occur all year round. In the northwestern part of Peninsular Malaysia, there are two peak seasons, the first in March–May and the second in September–December for oysters. In Sarawak, the first peak is in March–May and the second is November–December; in Sabah, the first peak in April–June and the second in October–November. Heaviest spatfalls occur 2–3 weeks after a sudden heavy rainfall.

For mussel spats, the first peak is in November–February and the second in May–June in Johore. Cockle spatfalls occur in specific areas and seasons, generally during late June to November with the peak period in September–October.

Other than cockles, oyster and mussel culture operations are still in very limited scale in Peninsular Malaysia which are practiced on part-time by fishermen. In Sabah commercial oyster farming is done by cooperatives. The rack-and-raft method produces about 18 tons/ha/yr.

The long-term strategy of the government is aimed towards export-oriented industry. However, small-scale, family-run operations are also being promoted as part of the Malaysia Plan to increase food production and raise living standards of the rural sector.

Research work on improving farming techniques, identification of sites, training and provision of technical advice to fisher-men on mollusc culture techniques are being intensified. In some places, provision of free oyster spats are being made to encourage initiation of oyster farming.

10.4 Singapore

The culture of the green mussel was very successfully carried out in Singapore. Basic research on bivalves were conducted which led to the findings that suitable mussel grounds are those which have phytoplankton concentration ranging from 17–40 μg Chl. a/1 seawater; water currents from 0.17 m–0.25 m/sec at floodtide and 0.25 m–0.35 m/sec at ebb tide; the primary productivity per hour from 73 μg to 100 μg carbon/m³.

A minimum of 0.5 ha plot of which 20–30 percent of effective culture area was used; the remaining space was utilized for anchorage purposes. Of the various methods tried by the Primary Production Department of Singapore (raft, longline, pole and bouchot), the raft method was found economically feasible. Higher profits are possible through highly mechanized large-scale operations. Production levels of 100–160 kg/m² has been attained in the raft method.

The marketability of the mussels was not attractive enough to encourage farmers to go into large-scale production. There is no mussel processing in Singapore where the product could be absorbed for future consumption or export. Further studies on high density depuration system for bivalves including oysters and cockles are necessary.

10.5 Brunei

This country is just beginning to develop aquaculture. At. present most or the food items are imported from abroad (Singapore, Malaysia and other countries). Plans have been made for coastal fisheries development and management including aquaculture. The country is presently engaged in manpower development to build up the future technical support for the country's fisheries development programme in general and aquaculture in particular.

Brunei is economically sound and the population enjoys one of the highest per capita income levels in the world. The country, therefore, is not confronted with the problem of small-scale fishermen as in the other ASEAN nations. The development of mussel or oyster farming would probably be in the context of producing high quality seafood for domestic consumption rather than to create alternative sources of income for fishermen.