10.1. Rice and Fish Project
10.2. Mussel and Oyster Farming
10.3. Mangrove Pen Culture
10.4. Mariculture Park
Freshwater aquaculture in the Philippines is under-developed especially when compared with brackishwater aquaculture. It still has a considerable opportunity for growth. The most logical places where freshwater aquaculture can be developed are the country’s irrigated rice farm areas, which according to latest statistics has a total area of 1,558,158 hectares. There is a need to re-introduce and promote rice-fish culture inspite of the failures of early attempts. Field trials repeatedly show the profitability of rice-cum-fish culture when compared to rice monoculture. The lack of acceptance among the farmers had been attributed to several reasons, among them, inadequate water supply from the irrigation system, incompatibility with the use of pesticide, the short culture period of high-yielding rice varieties which does not give enough time for the fish to grow to optimum market size, and lack of fingerlings at the exact period required.
In order to improve the project’s probability of success the proposed project should select only areas where the irrigation system is well developed and the water supply adequate or areas which are irrigated using shallow-tube wells. The farmers should be given two options, raising the fish together with the rice or raising the fish apart from the rice with the water serving as the common resource between the two. Such a project should be pushed not only by BFAR but by the Department of Agriculture through the LGUs with BFAR providing the technical backstopping for the fish culture component. Such a project should have the following components:
Additional incentives may be introduced in the form of a competition for the highest yield of rice and fish at the municipal and provincial levels where substantial cash prizes can be won by the successful farmers.
Mussels and oysters enjoy high acceptability in the Philippines. If the sanitation problem can be overcome it also has good export potentials. On the other hand, because they can be produced at very low cost, mussels and oysters can also be viewed as potential feed for high value carnivores such as groupers, lobsters and mud crabs which are easily exportable.
It is estimated that as of 1995 the productive area for oysters was only 228 ha and for mussels 361 ha (BFAR, 1997) or a total of 589 ha. The Philippines has a much large potential than what it presently has. In a pre-investment feasibility study conducted under the auspices of FAO for the Philippine government, Glude et al (1982) estimated that some 9,145 ha are suitable for oyster farming and 4,925 ha for mussel farming. This means only 3.9% of the available area are currently being used for oyster farming 4.6% for mussel farming. Of the potential areas for oyster farming 47.2% or 4,320 ha is found in Region I (Ilocos Region) and 27.3% or 2,500 ha within Region VIII (East Visayas). For mussel farming, a full 83.2% or 4,100 ha can be found within Region VIII also. This means a program to expand the present mussel and oyster production capability of the Philippines need to cover just the two regions and still achieve a high impact. East Visayas incidentally is also one of the relatively economically depressed areas in the Philippines.
Mussel and oyster farming as a livelihood alternative is often left out in Philippine fisheries planning because of the red tide problem. This is a pity because oyster and mussel farming requires very little capital investment, are labor intensive and their operation does not require very high skills. For sure the occurrence of red tide is a serious public health problem due to paralytic shellfish poisoning. However, it does not affect mussel or oyster survival and growth. It only affects their wholesomeness for human consumption and therefore their marketability. Once the red tide bloom disappears it does not take long for the mussels and oysters to become fit for human consumption. With a vigilant red tide monitoring and warning system in place, the red tide hazard can be greatly minimized. In fact red tides may be viewed positively in that during such episodes, the shellfish is allowed to grow and reproduce.
The real problem with red tide therefore lies not on its effect to the production system but to the cash flow of the affected oyster and mussel growers. During a red tide episode the growers, unable to market their produce will loss a ready source of cash for their daily needs. Additionally, it is not possible to predict how long a red tide bloom will persist. It can last for just a few days or could extend for several weeks. Mussel or oyster farming therefore should be introduced as a form of supplementary rather than the only means of livelihood. As a supplementary livelihood its main purpose will be for poverty alleviation rather than food security. Once in place, it shall of course also become a valuable source of animal protein. In this manner, the growers can then afford to wait for the red tide to pass.
Key to the success of any aquaculture project is the marketability of the produce. Glude et al (1982) identified three constraints to the marketing of oysters and mussels: wholesomeness of the product, unpredictable availability, and inadequate system for transporting them to market centers. If these constraints can be addressed demand can be increased and production will increase correspondingly in response to the demand.
To ensure product wholesomeness and protection of public health the proposed project should include the following components as proposed by Glude et al:
To increase demand the following actions recommended by Glude et al in 1982 are still valid:
The fallback position if the market for direct human consumption cannot be expanded is to make the product available as feed for raising high value carnivores. This should be resorted to only in case of product glut.
The viability of raising mudcrabs in a pen enclosure set within a mangrove forest without cutting down a single tree has been adequately demonstrated by SEAFDEC AQD in several sites in the Philippines. Bamboo pens lined with coarse-mesh nets topped by a plastic sheet all around to prevent the crabs from escaping are installed between the trees. Shallow ditches are dug to provide refuge to the crabs during low tide.
Crabs are stocked at the rate of one crab per square meter. Feed consists of fish with low market value and/or the golden snail which have become a pest. Undersize tilapia proliferating wildly in brackishwater ponds and is not used for direct human consumption also makes good feed. One hectare of such pen can produce as much as 1,400 kg of crabs which could mean a gross sales of about PHP280,000. The technology for producing mud crab seedstock is ready for dissemination and commercialization.
Even with most of the mangrove forests already gone due to large-scale fishpond development in the past, enough still remain along the fringes of the sea and along tidal rivers for such a project. Again like that for the rice and fish project this will require the provision of the same support services, training, provision of seedstock and financing.
Coastal or municipal fisheries in the Philippines has reached the point of diminishing returns. More and more fishers are chasing after less and less fish. There is a need to reduce fishing pressure to allow the fish resources to recover. This can be done only by encouraging fisherfolks to shift to other means of livelihood. Aquaculture, specifically sea-based aquaculture, beckons as one such alternative. The culture of fish or other marine organisms in the sea will mean giving fisherfolks a livelihood involving the production of the very same commodity, and in the very same environment, they are already familiar with. It can be considered a most logical choice.
The productivity of sea cages, particularly those set in deeper waters has already been adequately demonstrated by the few pioneering individuals. Properly regulated as is done in other countries, and with a judicious choice of species, it can be made sustainable. Candidate species for such a venture are milkfish, siganids or rabbitfish and saline-tolerant tilapia. Carnivore species such as seabass, Lates calcarifer, or for groupers, Epinephelus spp. should not be excluded. In areas where there is a possibility of producing tilapia biomass cheaply using only fertilizers or where there is a seasonal excess of sea-catch, these species may be included.
Milkfish is now the species being cultured in the pioneering sea cages. A circular cage with a diameter of 19 m and a netcage depth of 15 m set in waters 30 m deep was found to be capable of producing from 30 to 60 mt of milkfish. What more the milkfish produced, with an ABW of 0.5 kg are larger than those produced in land-based ponds within the same culture period of 120 to 150 days. Being reared purely on artificial diet in oceanic waters it also has no chance to develop off-flavor and can therefore command a better price. Milkfish diets are formulated with only 25% crude protein most of which are derived from terrestrial plants, mainly soybeans. Only 10.8% of the feed is fishmeal. (Feed Development Section, 1994)
Siganids are herbivores. They have long been cultured in brackishwater ponds and cages in the province of Pangasinan. Their culture in cages have also spread to the provinces of Misamis Ocidental and Negros Oriental. They can be fed with Gracilaria or Eucheuma which are easily grown with minimal costs. In Pangasinan scrap vegetables from the market is reportedly also used as feed and in Bais, Negros Oriental kangkong or swamp cabbage, Ipomeia aquatica. SEAFDEC AQD is now verifying the culture of siganids in marine cages in their Igang Station in Guimaras Island, Iloilo. The trial runs are still on-going but the results thus far have been encouraging and the culture economics and viability should be determined once the trials are completed.
Saline-tolerant tilapia, mainly O. mossambicus hybrids, have been tested in marine cages and have shown encouraging results. Tilapia diet is not much different from milkfish diet. Only it requires more fish meal (18.25%) than milkfish diet.(Feed Development Section, 1994). Both milkfish and tilapia diet are already commercially available and well distributed throughout the country.
The biggest problem in promoting sea cages as a technology option for the poor is the cost of the cages and their installation. The 19 m diameter imported fish cages reportedly cost more than PHP1.4 million (approximately US$36,800) installed with 50% of the cost apparently going into its mooring system. A locally manufactured circular cage with 15 m diameter reportedly cost about PHP600,000 (=US$15,789) installed. Smaller cages for less exposed sites are available at about PHP100,000 (=US$2,632) per 4-cage module, with each cage measuring 5 x 5 m, without the mooring.
The quality and design of the mooring system is important to ensure that the cages will be able to resist stronger than normal wind and wave action. If a mooring system can be provided as an infrastructure for mariculture in the same manner that fishing ports are provided for capture fisheries with fishing boats merely paying for mooring fee depending upon the size of the craft, the cost of installing sea cages can be greatly reduced.
The concept of a mariculture park envisions that the government provides the infrastructure for mariculture in the same manner that it provides farm to market roads, irrigation system and post harvest storage facilities for agriculture. Such facilities can even be constructed by the private sector using Build-Operate-Transfer (BOT) schemes already being employed in the building of roads and power plants. Marine engineers can design such mooring systems in a given area to a given specification. Plastic buoys can be used to maintain the mooring terminals at the water surface. Prospective fish cage operators will merely have to shackle their cages to the mooring point and pay a corresponding mooring fee based on the size of the cages. The fees can be based on a fair return on the investment for the infrastructure amortized over a period of 20 to 25 years just like roads and bridges.
In the Philippines such a mariculture park already has a legal framework. The Fisheries Code of 1998 requires that aquaculture areas be designated by local governments in case of municipal waters or by the Department of Agriculture for waters located outside municipal waters. Furthermore the appropriate government unit is also required to regulate the stocking density and feeding based on the carrying capacity of an area.
The development of a mariculture park is the best way for LGUs or the national government to implement the said provisions of the law. Without such an infrastructure, mariculture development will be difficult to monitor and regulate and cages will be installed anywhere based purely on market forces without any order to ensure sustainability. In a mariculture park the government can regulate the number and sizes of cages. The distances between cages will be pre-determined by the location of the mooring buoys. Regulating the number of cages is one way of regulating stocking and feeding. Floating wave breakers can be installed to soften the impact of wave action and reduce the risk of damage.
Appropriate sites should be identified based on relative exposure to heavy winds, frequency of typhoons, current direction and proximity to sensitive ecosystem such as a coral reef, as well as navigation. Appropriate policies can be developed as to access to capture fisheries within the mariculture park area. For a start a pilot mariculture park should immediately be designed and installed to determine technical and financial viability. Once found viable this can be scaled up and replicated in other similar areas.
Social preparations shall be required for the target beneficiaries, namely the impoverished fisherfolk. Mariculture will alter their pattern of livelihood. In fishing, the cash inflow is as often as their frequency of going out to sea. In mariculture, cash inflow is realized only after the stock is harvested which could take from four to six months depending upon the species. It is expected that during the first cycle of operations some amount of fishing will still be necessary in order for them to sustain their families.
Technical training on net-cage maintenance, stocking, feeding, size monitoring, harvesting should also be provided. Support services in the form of credit, extension service, cold storage and market linkage will be essential.
Aquaculture is the only way for fisheries production to grow with the population. The vast expanse of the sea remains as the only frontier for aquaculture development. It will be through pro-active acts such as the establishment of mariculture parks that development can proceed in an orderly, sustainable, and equitable manner.
