Species of tilapia in East African dams, with a key for their identification

Abstract

In East Africa there are at least 20 species of fish belonging to the genus Tilapia. It seems that certain species were at one time restricted to particular areas; for example, the "ngege", Tilapia escllienla, and the "mbiru", T. variabilis, occurred, as far as we know, only in the Lake Victoria catchment area and in Lake Kyoga. However, these and other species have been used for stocking dams throughout the three territories, with the result that their earlier geographical distribution has been greatly altered, and several species which were restricted in their distribution are now widely distributed. There are more than a dozen species of Tilapia in dams and ponds in various parts of East Africa. The culture of these fish is still carried out rather empirically; until more is known of the behaviour of the different species it is highly advisable that new dams should only be stocked with species already in the drainage area. A possible exception to this recommendation might, however, be made in favour of the easily recognizable weed-eating species T. zillii and T. melanoplellra. In all cases when new dams or ponds are stocked records should be kept of the origin of the Tilapia used.