2. WHAT IS AQUACULTURE ?
Aquaculture is organized production of
a crop in the aquatic medium. The
crop may be that of an animal or a
plant. Naturally, the organism cultured
has to be ordained by nature as
aquatic.
OR
Aquaculture is the farming of aquatic
organisms, including fish, mollusks,
crustaceans and aquatic plants.
3. OBJECTIVES OF AQUACULTURE
Production of protein rich, nutritive, palatable and easily digestible
human food benefiting the whole society through plentiful food
supplies at low or reasonable cost.
Providing new species and strengthening stocks of existing fish in
natural and man-made water-bodies through artificial recruitment
and transplantation.
Production of ornamental fish for aesthetic appeal.
Recycling of organic waste of human and livestock origin.
Land and aquatic resource utilization:(a) maximum resource
allocation to aquaculture and its optimal utilization; (b) increasing
standard of living by maximizing profitability; and (c) creation of
production surplus for export .
Providing means of sustenance and earning livelihood and
monetary profit through commercial and industrial aquaculture.
Production of industrial fish.
Production of bait-fish for commercial and sport fishery.
4. ORGANISATION OF AQUACULTURE
a) Semi-intensive-Adoption of mid-level
technology, partial dependence on natural
productivity, fertilization, supplementary feeding,
with stock manipulation, medium level inputs
and medium rate of production.
b) Intensive-Adoption of full complement of culture
techniques including scientific pond design,
fertilization, supplemental feeding or only feeding
without fertilization; full measure of stock
manipulation, disease control, scientific harvesting,
high level inputs and high rate of production.
c) Extensive-Adoption of traditional techniques of
aquaculture e.g. dependence on natural productivity
and little control over the stocks.
5. KINDS OF AQUACULTURE
Static water ponds.
Running water culture.
Culture in recirculating systems
Culture in rice fields.
Aquaculture in raceways, cages pens
and enclosures
Monoculture
Polyculture
6. Pond Culture
Static freshwater pond :
1. Ordinary fresh water fish culture
ponds are still-water ponds
2. They vary a great deal in water
spread area and depth.
3. Some are seasonal and some
perennial.
4. The ponds may be rain fed (also
called sky ponds) and/or may
have inlet and outlet systems
5. The water supply may be from a
stream or a canal or from an
underground source such as
wells, tube wells etc.
6. The water retentivity of the
ponds depends on soil
composition of the pond bottom
and subsoil water level.
7. Examples are: carp culture
systems in India, China,
Israel, Germany, etc
Brackish water ponds
1. The species different from
those cultured in freshwater
ponds
2. The principle of operation of
brackish water ponds is
different from those of
freshwater ponds.
3. The pond or the farm is
essentially located on a tidal
creek or stream and there is a
system of sluices to control the
ingress and egress of water
into and from the ponds
4. Examples are: Milkfish farms in
Philippines, Taiwan, Indonesia etc.
Brackish water fish farming is a fast
growing science.
7. RUNNING WATER CULTURE
At places where there is abundant supply
of water, common carp is cultured in
running water ponds.
A very high common carp production rate
has been achieved where there is plentiful
supply of running water of high dissolved
oxygen content and optimum range of
temperature for feeding.
Running water culture of common carp is
done in a small way in Europe, Indonesia
and Thailand.
9. Culture in Rice Fields
Culturing fish and growing rice together in the same paddy
fields is an old practice in Asia and the Far East.
Interest in producing rice and fish together had declined in
recent years because of use of fish-toxic pesticides required
to protect high yielding varieties (HYV) of rice introduced as
part of green revolution in Asia.
10. Aquaculture in Raceways:
Cages, Pens and Enclosures
Rigid structures
Flexible Structures
Floating Fish Cages
Cages with Rigid
Framework
Cages with Flexible
Framework
11. Advantages of cage culture
10 – 12 times higher yields than pond culture for comparable
inputs and area;
Prevents loss of stock due to flooding;
No question of seepage and evaporation losses;
No need for water replacement;
No problem of pond excavation and dependence on soil
characteristics;
Avoids proximity of agricultural areas hence reduces hazards of
pesticide contamination;
Can be conveniently located near urban markets avoiding the
need for fish preservation and transportation;
Eliminates competition with agriculture and other land uses;
Affords easy control of fish reproduction in Tilapia sp;
Complete harvest of fish is effected;
Optimum utilization of artificial food;
Reduced fish handling;
Initial investment relatively small.
12. Limitations of cage culture
Difficult to apply when water is rough;
High dependence on artificial feeding.
High quality feed desirable especially in
respect of protein, vitamins and
minerals. Feed losses are possible
through cage walls.
At times interferes with natural fish
populations round cage.
Risk of theft is increased.
13. Finfish Culture-cum-Livestock Rearing
In this system of culture, fish pond water surface maintains
brood stock of ducks, rear one-day-old ducklings as well
as 14–21 day-old advanced ducklings.
This is a synergic system of mutual benefit to each
organism cultured: duck droppings manuring the pond,
duck foraging consuming a variety of unwanted biota for
fish culture such as tadpoles, frogs, mosquito and
dragonfly larvae, mollusks, aquatic weeds etc.
One duck produces about 6kg of droppings in 30 – 40
days in a pond and 100kg of duck manure may increase
fish flesh to the extent of 4 –6kg
14. MONOCULTURE
Monoculture, as the name implies, in the culture of a single
species of an organism in a culture system of any intensity,
be it in any type of water, fresh, brackish or salt.
FOR e.g. Tilapia culture in India
Rainbow trout (Salmon gairdneri) culture in several
countries.
Channel catfish (Ictalurus punctatus) in U.S.A.
Catfish, Clarias gariepinus in Africa.
15. POLYCULTURE
Polyculture, as the name implies, is the culture of several species in
the same water body. The culture system generally depends on natural
food of a water body sometime augmented artificially by fertilization
and/or by supplementary feeding. If artificial food is given it is a
common food acceptable to all or most species that are cultured.
FOR e.g. Polyculture of several species of Chinese carps in China,
Taiwan etc.
Polyculture of several Indian major carp species in India.
Polyculture in Indian major carps, Chinese carps and other fish in India
(called composite fish culture in India).