The two approaches commonly implemented on a small scale are:
1. Local pond fish farming
2. Open water fish farming in lakes, rivers, dams, and reservoirs
The benefit to low-income farmers is that they are able to invest in fish cultivation when there is sufficient income, which will then be able to generate additional income and food when other sources of income are limited.
In the Philippines, much of the area is flooded annually during the monsoon season as water flows into the country through rivers, lakes, dikes, and dams. This provides an extensive range of habitats for wild and cultivated fish species. Fish catches are highest after the monsoon rains when supplies of other food, such as rice, are low. With no much water, fishing plays a vital role in the economy of rural villages.
FISH FARMING OPTIONS
A. Capital Intensive
One of the main trends in fish culture over the years has been towards capital-intensive, high-input high-yield systems which can dramatically improve the rate of production if operated in ideal conditions.
The development of practical hatching techniques has vastly improved fish cultivation and allowed careful breeding and selection of desired species to take place. Although these techniques were introduced some years ago, it has taken time for them to become established. Commercially produced fish have become a significant proportion of the total fish supply.
But intensive cultivation methods increase the cost of fish production beyond the reach of poorer farmers. Consequently, alternative low-cost approaches have been promoted by NGOs working in the country.
B. Fish Farming for the Poor
An enormous variety of water bodies like rivers, lakes, ponds, etc. are dispersed throughout the countryside offering potential for fish cultivation, but the general lack of capital, access to resources and knowledge means that farmers are unable to provide all commercial inputs required for intensive production methods.
An alternative low-cost approach is more appropriate for people, relying on existing water bodies and natural vegetation and household waste, supplemented with animal protein in the form of snails homemade supplements for fish feed.
Many NGOs are adopting strategies to minimize the inherent riskiness of fish culture by undertaking research into low-input systems, low-cost technology, fast-growing species and alternative management practices.
C. Pond Culture
Site selection is an important factor in the success of a fish farm but he ideal site is usually available to poorer families. Site selection will depend on a number of factors:
. The fish being raised
. Soil quality, which affects water supply and productivity
. Adequate water supply
. Land ownership
. Marketplace and market conditions
. Fish food and other inputs available to the farmer
. Groups adjacent to water
. More than 1-meter retention capacity of water for at least 6 months of the year
. Pollution free
Ideally, the fishpond should be 0.5 to 1 meter at the shallow end and sloping 1.5 to 2.0 meters at the drain end. Drain valves, baffle boards or tilt-over standpipes should be incorporated into the design. It should be possible to drain the pond within 3 days. The edges of the pond should have a slope of 2:1 or 3:1 on all sides.
If possible the pond should be located to take advantage of the effect of the wind on the surface of the pond to mix the water, although locations that are too windy can cause erosion of the dikes. If the site is very windy the long side of the pond should be at right angles to the prevailing wind. Hedges and trees can be used to protect the pond.
In practice, existing ponds and pools are abundant in the Philippines, often located near farmers' homes. Small-scale fish cultivation is mainly secondary to occupation to farmers. These ponds tend to be small(less than 0.25 acres) and do not have any water drain facility. They are commonly referred to as fishponds but are in fact burrow pits, where the earth has been removed for the building.
Fish breeding is just one of the activities that ponds are used for. Other uses may include domestic water use, washing, irrigation, or duck keeping. Ponds are occasionally integrated into paddy fields as additional ditches. Consequently, the ponds have many limitations for producing fish.
In managing the ponds there are potential problems to be considered, including:
. Broken pond banks, check the pond walls on a regular basis
. An irregular water supply, too much water in the monsoon season and too little in summer.
. Predators, check the pond for signs of snakes and rat holes. The Boal fish is a particular menace that eats smaller fish.
. Grazing animals can damage the pond banks and should be kept away.
. Silting or a build-up of organic matter, check the bottom of the pond and scoop silt out when needed. Mud on the bottom can be agitated with a rope to release harmful gases.
. Leakages, check the inlets and outlets on a regular basis.
. Fish diseases, check the fish regularly.
. Poor water quality, lime can be added to improve water quality.
D. Open Water Fish Farming
Open water fish farming is suited in the Philippines with its many water sources. Cages or pens are used to separate an area of large water bodies for fish cultivation. The selected water source should be of good quality with low turbidity.
Dams and reservoirs primarily exist to store water but as a secondary function these water bodies can be stocked with fingerlings or fry and the fish can be harvested later using nets. In rivers a slow current is necessary and there should be little disturbance from water traffic.
Disadvantages:
. Fish farmers have little control of the water, as they do not own the dams or reservoir.
. Water cannot be drained, as the main function of the resource is to provide water.
. There are likely to be more predators of the fish.
. It is not possible to feed or fertilize the water, as occurs in more intensive fish farming, so there is a reliance on natural fish food.
. There is a potential risk from disease but stock held in small cages scattered around villages will probably be less vulnerable.
. The risk of theft an vandalism is a serious problem in some places. This is real for the poorest people who are seen as easy victims.
. A significant expansion of cage culture in some villages could lead to local depletion of snail or other foods for ducks and other domestic and wild animals.
. Multiple ownership of ponds can be a major drawback to the effective use of such resources. Consensus over access to the water for the poor has to be developed.
FISH CAGES
Cages are used as a form of farming in their own right within flowing or large water bodies and can also be used in small pond fish culture to protect fingerlings in the initial stages of development. Small cages with a capacity of 1 cu. m. are suitable for fingerling protection. The cage can hold up to 300 fish at a time. People grow fish in their local ponds using a simple cage known as "hapa", which acts as their homes, floating just below the surface of the pond.
Cage Construction
Cages can be made using cheap materials. Bamboo poles form an outer frame that is covered in netting. Inside is a "nursery" for the younger, more delicate fish, and floats are added in the corners.
A cage is a very simple means of restraining fish in one place and it can be easily made from local materials. Cage design must incorporate certain physical properties, likethe ability to hold fish securely but also within the financial means of the operator. The cages presently used are small between 1 and 2 sq. m. inexpensive and easy to construct.
Farmers use both fixed and floating cages. In general, fixed cages are installed in water where the depth is relatively low and bamboo poles can be fixed into riverbed or substrate. Floating cages can be used in deep waters. Floating cages tend to be easier to manage but when selecting the type and design the following should be considered:
. Ability
. Input availability
. Natural disaster
. Type of body of water
. Water depth
. Water current
. Water retention period over one year
. Social problems
. Cage management
For more info, contact:
Bureau of Fisheries and Aquatic Resources
PCA Bldg. Elliptical Road, Diliman, Quezon City
web: www.bfar.gov.ph
source:www.practicalaction.org
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