Oyster and Mussels in Western Visayas
By Giselle PB. Samonte
Research should focus on increasing production and preventing red tides.
The slipper oyster (talaba) and the green mussel (tahong) are the only mollusk species being farmed in the Philippines.
The Western Visayas region in the central Philippines is one of the major sources of oysters and mussels, which are farmed for their meat. Production is mainly for the domestic market.
The need of the people in the region to augment their income from fishing has led to the proliferation of oyster and mussel farms.
The farms started operations as early as the 1950s. There are today an estimated 2,000 coastal families in the region which are engaged in the mollusk farming. Oysters are farmed along rivers using the bottom, stake, rack-hanging and raft-hanging methods.
In the bottom method, oyster shells or large stones are scattered on the sea bottom for oyster spat fall.
In the stake method, whole or halved bamboo poles are used as substrates for oysters.
In the rack and raft-hanging methods, about 10 oysters’ shells are tied to a plastic strap and hung on bamboo poles. These bamboo poles are tied to a bamboo rack or raft. Of the four oysters culture methods, the rack and raft-hanging methods are considered the most productive.
On the other hand, mussels are farmed in river mouths and bays using the stake and raft-hanging methods. In both methods, the farmers use bamboo poles as substrate materials. The average area for mussel culture is 700 square meters. Of the two, the stake method is more productive.
The cost of capital assets for oyster and mussel culture is about P2, 000 per farm with the owner’s equity being the main source of financing. Capital assets include a non-motorized boat, a nipa hut on the farm site, tools (e.g. bolo, iron bar for harvesting) and wooden bar.
Production costs incurred are for the purchase of substrate material, hired labor for the construction of racks or rafts and for harvesting, transportation fees, and municipal permits. They earn higher net profits from mussel farming than oyster farming.
The farmers encounter various problems over which they have little or no control. These are pouching (a social problem), and environmental, culture and marketing problems. Environmental problems include mortality of oysters and mussels due to floods, typhoons, fishpond effluents, and siltation or sedimentation caused by runoffs. Absence of spat, space competition by other mollusks, high mortality during dry months, predators and substrate borers, and attachment of hydroids are some of the culture problems. Marketing problems include lack of buyers especially when the red tide phenomenon occurs and low market prices.
Oyster and mussel farming contributes about 20 percent to the total household income of a small-scale fisherman. Research and development efforts should now be directed toward strengthening the industry in the region. The formation of cooperatives must be encouraged to enhance the farmers’ bargaining and market capability, applications for soft loans, and use of market information. Research should be geared toward increasing production and on how to prevent red tide. Finally, the government should strictly enforce existing laws and policies, especially the securing of licenses and permits to culture shellfish. – Condensed from NAGA, the ICLARM Quarterly