Milkfish: The King of Fish
by Henrylito D. Tacio
Historically, milkfish fry abound in the country. In recent years, however, the number collected has been dwindling due to the destruction of natural habitats brought about by the extensive conversion of mangrove areas to fishponds, destructive fishing methods and environmental degradations, among others. Consequently, with the decrease in seed supply, the cost6 of fry and fingerlings has increased significantly over the years.
Normally, milkfish fry appears in different places and various seasonal peaks. Areas like Southern Leyte, Western Samar, Bohol, Negros Oriental and Occidental, Antique, and Iloilo have two peak seasons: March to July and October to November. Provinces like Cotabato and Zamboanga del Sur have fry available year-round.
“Livelihood Options for Coastal Communities,” published by the Laguna-based International Institute of Rural Reconstruction, says peak gathering days occur during high tides after two or three days following a new moon or a full moon. The gonadosomatic index (GSI) or peak-spawning season of milkfish starts in March to June and drops in August to September. During the breeding season, the rising GSI value coincides with rising seawater temperature. Spawning regularly occurs among five- to – seven yea old sabalo in the wild. Fertility is about 300,00 to one million eggs per kilogram weight of sabalo.
Several milkfish fry collection methods are practiced in the Philippines. This includes fry barriers of fences, seine nets and “bulldozer” nets.
The collected bangus fry are placed in well-ventilated containers, preferably wooden vats or big earthen jars filled with clean brackishwater. The containers must be kept in cool areas. Overexposure to sunlight should be avoided. The fry should also be brought to the concessionaires’ buying stations without delay.
Raising milkfish can be done using different production systems in freshwater and in brackishwater. Depending on the available resources and level of management, the culture methods can vary from the traditional or extensive systems, the modified extensive, to semi-intensive and intensive.
Milkfish can also be reared with other species. In freshwater ponds, milkfish can be cultured with mullet, tilapia, and carp with yields averaging 7,500 kilograms per hectare. In brackishwater ponds, shrimps, mudcrab, seabass, and seaweed are the most common species combined with milkfish.
According to the PCAMRD, the rates of stocking of the different species depend on their biological requirements, farmers’ preferences, and the market demand for the cultured products.
Is there money in raising milkfish? A study on the cost and returns of milkfish production was conducted by the agriculture department in the provinces of Bulacan, Iloilo, and Negros Occidental in 2001. The result shows that Bulacan incurred the highest average production cost at P32, 202 per hectare while in netted P41, 922. Average production costs per hectare were lower in Negros Occidental at P20, 390 and in Iloilo at P14, 047. The net returns were calculated at P15, 271 and P10, 746, respectively. Certainly, then, there is money in bangus production.
source: MARID agribusiness, January 2006