Small-scale fish farming
Practical Action
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.
Open water fish farming
Open water fish farming is particularly suited to Bangladesh 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.
Fish cages
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 metre 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".
Figure 2: Bilkish Begum and Hamida Begum working with
fish cages. Photo: Practical Action / Zul.
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