Tilapias are just ordinary hardy fish that can be reared by anyone in the tropics who has even a very poor pond condition. Tilapia can be reared by people who are poor, illiterate because to rear them we do not need any special technical knowledge, maintenance is least costly, feeding is very easy and simple and they multiply themselves very fast and in great number, They can withstand most of the adverse conditions which are found in a poor small and marginal farmer's situation. Even the man who has only very little land and a very small pond or a tank can rear them for his own home use or for sale. Therefore, it can be said to be the poor man's aquaculture special fish.
Tilapia are warm water fishes though the optimum temperature range for their growth is found to be between 20 to 30 degree centigrade. The minimum temperature that it can withstand is about 12 to 13 degree centigrade and the maximum even up to 40 degree centigrade. Their respiratory demands (energy requirements through oxidation during respiration) are least and hence they can be reared in less oxygenated water. They can be easily transported from one place to other without caring much for them. Most of the special care euryhaline (chemically varying in nature) and withstand brackish water. They breed very easily and look after the young ones very well. Some of them keep their young ones in the mouth to protect them from any danger to which the young ones may be exposed
Though there are many species of tilapias some of them are more suited to economic rearing because of their high yielding nature. They are described here.
- Tilapia mossambica
Tilapia mossambica originated in the east and the south of Africa down to Natal. The same species was discovered in Asia in 1939 in the east of Java. Whether they were introduced into those two areas or not is not clear to anyone. During the Second World War and later this species spread over in Java in may ponds with brackish water and then in the fresh water, in the open water as well as in artificial ponds. It was the Japanese who introduced tilapia into most of the Indonesian islands, in Malaysia and Taiwan. After the war they were also introduced into Thailand, the Anties and south of United States.
- ilapia rendalli
Tilapia rendalli is said to be originated in the west of intertropical Atrica. It spread through the farms of Zaire from 1947 and has been introduced into numerous Ponds inequatorial Africa. Efforts are being made to introduce them to Brazil and Thailand.
- Tilapia macrochir
Tilapia macrochir is originated in the southern part of Central Africa. Since 1947 this breed has been cultivated in Zaire and elsewhere in Africa where it is associated with Tilapia melanopleura.
- Tilapia nigra
Tilapia nigra is believed to be originated in Kenya and is mostly reared in that country though they are being introduced into other parts of the world also
- Tilapia nilotica
Tilapia nilotica originated in West Africa and is being cultivated in that region.
