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Tilapias are small to medium sized African fish that are the focus of major fishing and aquaculture efforts. They are members of the family Cichlidae and resemble perch or bass in general shape, but as with all cichlids they have a single, long dorsal fin instead of two, as is typical of perch and bass. They inhabit a variety of fresh and, less commonly, brackish water habitats from shallow streams and ponds through to rivers, lakes, and estuaries. Most tilapias are omnivorous with a preference for soft aquatic vegetation and detritus.


 


Tilapia are native to Africa and the Levant, but have been widely introduced into tropical fresh and brackish waters around the world. Some introductions, as in Florida and Texas, were planned, most likely caused by purposeful introductions by government agencies to control other invasive aquatic plants, etc. [8]. More often, however, the fish have been introduced deliberately for commercial or industrial scale aquaculture. Because tilapia are large, fast growing, highly fecund, and tolerate a wide variety of water conditions (even marine conditions), once introduced into a habitat they generally establish themselves very quickly. In many places, particularly Florida and Australia, feral populations of tilapia have had detrimental effects on ecosystems. On Rennell Island, the Rennell Island Teal became extinct after introduced Oreochromis mossambicus multiplied in the absence of predators (the local population did not fancy the fish); the ducklings of the small waterbird were simply eaten away by the tilapia.

The larger Tilapia species are generally not viewed as good aquarium fish because they eat plants and tend to be very disruptive, digging up the substrate and fighting with other fish. Only the smaller west Afrian species, such as Tilapia joka, and those species from the crater lakes of Cameroon have become at all popular among aquarists.

On the other hand, they are hardy and easy to keep, provided they get enough space. They mix well with non-territorial cichlids, armoured catfish, tinfoil barbs, garpike, and other robust but peaceful fish. Some species, including Tilapia buttikoferi, Tilapia rendalli, Tilapia joka, and the brackish water Sarotherodon melanotheron melanotheron, are attractively patterned and decorative fish.


Broadly speaking, tilapias of the genus Tilapia are substratum spawning cichlids, meaning that the fish form pairs, lay the eggs on the substrate, and then guard the eggs and fry. Tilapias of the genus Sarotherodon are mouthbrooders, with either both parents or just the male looking after the eggs or fry. Finally, tilapias of the genus Oreochromis, by contrast, are also mouthbrooders but in this case it is normally the female that looks after the eggs and fry. Groups of male Oreochromis form leks where they compete with one another for opportunities to mate with the females. Beyond this, they show no interest in the eggs or fry and do not extend any broodcare to their offspring at all.

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 Kingdom: Animalia

 Phylum: Chordata

 Phylum: Osteichthyes

 Class: Actinopterygii

 Order: Perciformes

 Family: Cichlidae