hati kering: AQUACULTURE : CURRENT BIVALVE STATUS IN MALAYSIA

1.0 Introduction

Aquaculture in Malaysia consists of freshwater and brackish water production. Brackish water aquaculture dominates the production with 136,000 tonnes valued at USD 236 million (FAO 2005). The main species of brackish water aquaculture are marine finfish, black tiger shrimp and shelled molluscs. Shell mollusc culture such as cockles is mainly found in the state of Perak and the culture of oysters in the state of Trengganu. Green mussels are mainly cultured in the states of Johor, Melaka, Negeri Sembilan, Selangor and Perak. Currently the major culture systems used are brackish water culture of shrimps and marine fish in ponds, marine fish in floating net-cages, mussel culture in rafts and oyster culture in rafts and racks.

2.0 Culture and production of mussels in Malaysia

Culture of the green mussels, Perna viridis, holds considerable potential in Malaysian coastal waters (Marzuki 1998). The production increased to 7702 mt in 2003 from 5785 mt in 2002 (FAO 2005). Most of the production is in the western part of Peninsular Malaysia in the states of Johore, Melaka, Perak, Selangor, Negeri Sembilan and Penang and a little in the state of Sabah in East Malaysia (DOF 1996). In the state of Sarawak, there is no production record of green mussel. The brackish water aquaculture in Sarawak is black tiger shrimp culture in ponds, marine fish culture in floating net cages and crab culture in pens. However, it is reported that shellfish such as giant clams, razor clams and white clams are found naturally and are becoming important for commercial, recreational and subsistence activities in Sarawak (Oakley 2000). Green mussel appears to be already consumed in Sarawak and the import of this product increased from 1 mt in 1996 to 7 mt in 2000 (Pada Bijo, personal communication). On the other hand, Malaysia was importing 491 mt of mussel in 2003 even though the green mussel production in that year reached 7700 mt (FAO 2005). Thus, the introduction of green mussel farming in state of Sarawak could meet local demand as well as contribute to the balance of trade or export earnings of the nation.

The mussel farming is considered to hold considerable potential in Malaysian coastal waters (Mazuki 1998). The production increased from 1200 mt in 1993 to 7700 mt in 2003 (Table 1and Figure 3). Nevertheless this production (Table 1 is still below that of the neighbouring countries such as Thailand and the Philippines. Green mussel, Perna viridis (Appendix V) is the main species for aquaculture operation in Malaysia (Ong and Rabihah 1989). The culture activity started in the Johore Straits in the southern coast of Peninsular Malaysia due to availability of natural seed. It spread to the western coast of Peninsular Malaysia especially the state of Melaka where natural spat are available and Perak by obtaining the seed for transplantation from Johore and Melaka. With the development of culture systems through work done by Fisheries Research Institutes and the initiative of the government the mussel culture is now spreading to other parts of Peninsular Malaysia by transplantation of young mussels collected on polypropylene ropes from sites with natural spat (Choo 1979). There are more than 250 culturists managing over 370 rafts (78,000 m2) located in the states of Johor, Melaka, Perak, Negeri Sembilan, Selangor, Penang and Sabah (DOF 1996).

Figure 1: Production trends of green mussel in Malaysia 1986 – 2003 (FAO 2005).

3.0 Rack culture

3.1 Mussels, Perna viridis

Mussels culture has increased by 122.91% to 8,993.71 tonnes in 2008 from 4,034.77 tonnes in 2007. Mussels production value increased to RM5.56 million in 2008 from 3.20 million in 2007, an increase of 73.75%. Johor state remains a major producer with a production of 8,483.07metric tons valued at RM3.61 million which is 94.32% the production of mussels country. Mussels cultures area increased 30.84% of 188,095.73 square meters in 2007 to246,105.06 square meters in 2008. This increase was due to increased acreage in Penang of 70,500.00 square meters.

3.2 Oyster

Oysters culture was decreased by 68.33% to 275.47 tonnes in 2008 compared
869.72 tonnes in 2007. Value of production also declined 72.94% to RM1.25 million in 2008 from RM4.62 million in 2007. Sabah is a major producer of oysters of 221.05 tonnes valued at RM1.25 million. Area of the oysters culture was declined 31.67% to 272,102.49 square meters in 2008compared to 398,208.33 square meters in 2007.

4.0 Bivalve production value