For many people in most third world countries, small-scale fish farming is an important opportunity to generate income and is a significant nutritional source providing protein-rich food all year round. It comprises of a range of options that can be adapted to suit the needs and capacity of people living in rural areas.
The two approaches commonly implemented on a small scale are:
- Local pond fish farming
- 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 foods, such as rice, are low. With so 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 recent 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, including rivers, irrigation canals, flood plains, beels (large depressions), lakes and ponds are dispersed throughout the countryside offering considerable potential for fish cultivation, but a general lack of capital, access to resources and knowledge means that many farmers are unable to provide all the commercial inputs required for intensive production methods.
An alternative low-cost approach is more appropriate for many people, relying on existing water bodies and natural vegetation and household waste, supplemented with animal protein in the form of snails and 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 the ideal site is usually not
available to poorer families. Site location will be dependent on a number of factors:
- The fish species being raised.
- Soil quality, which affects water quality and productivity.
- An adequate supply of water.
- Land ownership.
- Marketplace and market conditions.
- Fish food and other inputs available to the farmer.
- Groups adjacent to water.
- More than 1 meter water retention capacity for at least 6 months of the year.
- Pollution free.
Ideally, the fishpond should be 0.5 to 1.0 meters at the shallow end and sloping to 1.5 to 2 .0 meters at the drain end. Drain vales, baffle boards or tilt-over standpipes should be incorporated into the design. It should be possible to drain the pond within three 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 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 to farmersâ€™ homes. Small-scale fish cultivation is mainly a secondary occupation for 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 â€œborrow pitsâ€, where earth has been removed for building.
Fish breading is just one of the activities that the 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 many 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 the summer.
- Predators; check the pond for signs of snake 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 out of the way.
- Silting or a build up of organic matter; check the bottom of the pond and scoop silt out when required. Mud on the bottom of the ponds can be agitated with a rope to release harmful gasses.
- Leakage; check the inlet and outlet on a regular basis.
- Fish diseases; check the fish on a regular basis.
- Poor water quality; lime can be added to improve the water quality.
D. Open Water Fish Farming
Open water fish farming is particularly suited in the Philippines with its many water sources. Cages or pens are used to separate an area of larger 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 bodies of water can be stocked with fingerlings or fry and the fish can be harvested later on using nets. In river locations a slow current is necessary and there should be little disturbance from water traffic.
The disadvantages are:
- Fish farmers have little control of the water, as they do not own the dam 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 in the water.
- It is not possible to feed or fertilize the water, as occurs in more intensive fish farming, so there is a reliance on naturally occurring fish food.
- There is a potential risk from disease but stock held in small-scale cages scattered around villages will probably be less vulnerable than stock held in more concentrated and centralized commercial systems.
- The risk from theft and vandalism is a serious problem in some places. This is especially real for the poorest people who are perceived as easy victims.
- A significant expansion of cage culture activities in some villages could lead to local depletion of snail or other foods, to the detriment of 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.
Cages are used as a form of farming in their own right within flowing or large bodies of water 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 one cubic meter 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 fish cage known locally as a “hapa”. A few young fish are put into each “hapa”, which acts as their home, floating just below the surface of the pond.
Cages can be made using a few cheap materials. Bamboo poles form an outer frame that is covered in netting; inside is a “nursery” section for the younger, more delicate fish; and floats are added at the corners.
A cage is a very simple means of restraining fish in one place and it can be easily made using local materials. Cage design must incorporate certain physical properties, including the ability to hold fish securely but also to be within the financial means of the cage operators. The cages presently used are small in size, measuring between 1 and 2m3, inexpensive and simple 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 the riverbed or substrate. Floating cages do not have this limitation and can be used in deep water. Floating cages tend to be easier to manage but when selecting the type and design the following points should be considered:
- Input availability
- Natural disaster
- Type of water body
- Water depth
- Water current
- Water retention period over one year
- Social problem
- Cage management
For more information, contact:
Bureau of Fisheries and Aquatic Resources
Dept. of Agriculture
PCA Building, Elliptical Road
Diliman, Quezon City
Tel. Nos. (632) 929-8074 / 929-9597
source: The original article appeared in www.practicalaction.org and was intended for Bangladesh fish farming.