You may like it steamed, deep fried, grilled or “sashimi”, but do you know how the delectable lapu-lapu is grown? The grouper fish or lapu-lapu in the Philippines is widely cultured in the pristine waters of Palawan and in other parts of the country. This commodity is valued for its superb taste and its big potential in the export market.
The R&D workers in a research outreach station (ROS) in Puerto Princesa City, Palawan believe that this industry could rake in revenues for the country and become a steady source of income for the growing population of coastal dwellers. Thus, the technology “Grouper Culture in Cages” is being endorsed for commercialization through the National Technology Commercialization Program (NTCP), a major program promoted by the Department of Agriculture Bureau of Agricultural Research (DA-BAR) for the enhancement and promotion of agriculture and fisheries technologies.
The Inland Sea Ranching Station (ISRS), one of the Research Outreach Stations (ROS) of DA’s Bureau of Fisheries and Aquatic Resources (BFAR) Region 4B in Puerto Princesa City, Palawan, is the source of the technology. ISRS started to commercialize the technology for adoption of fishfarmers in January 1996 in Puerto Princesa and in other parts of Palawan such as the Malampaya Sound and Calamianes Group of Islands.
Palawan is ideal for grouper culture because this fish commonly inhabits coastal waters, rocky shores, and coral reefs. The aquaculturists of ISRS thoroughly studied the set-up of the culture cages for grouper production from site selection, net cage specification and construction to grow-out, harvest, post-harvest, and simple cost and benefit analysis of starting a business by adopting the technology.
According to Mr. Roberto R. Abrera, Aquacultural Center Chief II and Manager of BFAR’s Regional Fisheries Research and Development Center Region 4B (MIMAROPA), there are about 40 cultivable species of grouper belonging to family Serranidae but only two are popularly cultivated at present, the orange-spotted (Epinephelus coioides) and black-spotted (Epinephelus malabaricus) grouper. In Palawan, the orange-spotted grouper is locally known as “green grouper” while the black-spotted grouper is “lapu-lapu”.
Abrera said it is difficult to differentiate one species of grouper from the other because of its ability to change colors. Nevertheless, their colors vary under different environmental conditions and physiological states but their general characteristics are the spots, stripes, and blotches in skin, wide mouth, and protruding jaw. Other cultivable species include the brown marbled grouper, dusky-tail grouper, leopard coral trout, barred-cheek coral trout, and humpback grouper. The source of stock for grouper fingerlings for commercial cage production is apparently still dependent on the wild, but collecting them is not a problem because they usually gather in coastal waters near mangrove areas, estuaries, and seagrass beds.
In selecting the site for setting-up the floating net cages, water condition, depth, and quality should be considered. “Net cages must be set-up in calm waters such as lagoons, coves, inlets, or bays to avoid strong waves and current that may damage them,” advised Ms. Myrna B. Candelario, ISRS Officer-In-Charge and Senior Aquaculturist. “The water must also be free from pollution and the cages are within the fish cage belt or mariculture zone authorized by the local government,” she added.
Since the ISRS aims to disseminate technologies that are environment-friendly, simple, and low cost, they are recommending the use of indigenous or available materials in constructing the net cages. The following are the basic requirements of assembling a floating cage: cage frame made of galvanized iron pipe, wood or bamboo; concrete blocks, plastic containers filled with sand and galvanized pipes as sinkers; four pieces of plastic containers or empty plastic drums tied together as floaters; and nets. The floaters must be securely tied to the cage frame. The ideal structure is 10 sq m with nine sections measuring 2.5 x 2.5 m each. The net which should resemble an inverted 3 mosquito net should measure 12.5 cm (2.5 x 2.5 x 2 m). It should be fitted in the cage frame using monofilament twine. Finally, for its anchor, concrete blocks should be placed beneath the four corners and mid-section of the structure. Its weight should be two times the weight of the cage.
According to the aquaculturists of ISRS, nursing the newly acquired seedstock is necessary for the conditioning of fish prior to grow-out culture in the net cages. Grouper fry that are only 2 to 10 cm in length should be separated from shooters or those which are beyond 10 cm in size to avoid cannibalism. Stocking rate should 3 be 15 20 fishes/m. Feeds can be shrimps or finely chopped trash fish given at a rate of 10 percent of the total body weight. The fry should be fed two to four times daily. When stock size is already more than 10 cm in length, feeds could be given at a rate of 5% of the stock’s total weight.
In a span of six months, the fish could grow up to 750 grams or more and is ready for harvest. Harvesting is simply done by lifting the net, but this should be done with care since putting the fish to stress can damage their quality. They should not also be fed a day prior to harvest.
The harvested grouper could be sold alive and currently has a starting price of P250/kg. The total production cost of grouper culture including setting-up the net cages is estimated at P212,888. Since two cropping cycles is possible, total sales of P364,500 is likely. The estimated return on investment is also high at 71 percent, with a net income of P151,612.
If one is interested in adopting this technology for business, aquaculturists advise that the suitability of the site and abundance of fingerlings and fishfeed must be ensured. Further, proper cultural management and marketing strategy are important to succeed in the culture of grouper fish. Officials of ISRS caution about the “copycat mentality” of some particularly in this technology. “Some individuals and businessmen decide to adopt the technology on impulse when they have seen its potential without getting the right information and skills necessary to do it well. Eventually they give up or are able to produce but not with the quality and consistency that is needed to thrive in the business,” they explained.
For more information, contact:
Bureau of Agricultural Research
Department of Agriculture
3/F RDMIC Bldg., Visayas Ave.
cor. Elliptical Rd., Diliman Quezon City 1104
Trunklines: 928-8505 or 927-0226
Local Nos. 2043, 2042, 2044
E-mail: [email protected]
D.A. Compound, Elliptical Rd., Diliman,Quezon City
Tel. Nos. (632) 929-6065 to 67 / 920-3991 / 928-1134
source: Miko Jazmine J. Mojica of www.bar.gov.ph