Recent status of exotic tilapia species in Turkey

Abstract

One of the most controversial issues in Turkey about the occurrence of the exotic fish species belonging to the family Cichlidae. Up to date, starting the 1970’s a total of seven species including Coptodon rendalli, C. zillii, Oreochromis aureus, O. mossambicus, O. niloticus, Sarotherodon galilaeus and Tristramella simonis introduced to Turkey for aquaculture purposes or accidently. Then these species have deliberately released or escaped from research and aquaculture facilities establishing themselves into natural environment of Turkey. In other cases, tilapia have been introduced into new aquatic habitats via aquarists or ornamental fish farmers. There was not any reliable record about establishment of O. mossambicus, S. galilaeus and T. simonis in Turkey. It is observed that now C. rendalli, C. zillii, O. aureus, and O. niloticus and/or hybrids of them exist in the wild water system of Turkey. Another problematic issue is that species identification of specimens found in nature is impossible due to the fact that hybridization of different species of Cichlidae. By the way, the range of the species belonging to the family Cichlidae in Turkey is determined that a need for detailed genetic studies to assess the current status.