48 SEPTEMBER 2019 • WORLD AQUACULTURE • WWW.WAS.ORG resulted in exponential growth from 10 to 550 g in seven months. No incidences of mortality or cannibalism were recorded in this experiment and the fish did not appear to be overly sensitive to low dissolved oxygen and constant sampling (Gregory 2006). Nile perch will accept trash fish, strengthening the possibilities of its captive culture. During the current experiment, fish in cages were fed on small trash fish consisting of R. argentea and haplochromines bought from fishermen. The impact of cage fish farming on the aquatic environment by the release of nutrients that affect water quality can bring about conflict with multiple water users and also have a negative feedback effect on the caged fish. This can be due to algal blooms which can lead to reduced oxygen causing fish mortality (David et al. 2015, Degefu et al. 2011, Hallare et al. 2009). There were no such effects recorded in this study because no artificial diet was fed to the fish in the cages. Cases of theft, fish poisoning and cage breakages by strong waves have been reported in Malawi (FAO 2007). Site selection and security are therefore important factors to consider while setting up cage culture facilities. Cages occupy space on the surface of water bodies and, if poorly positioned, may disrupt navigation or diminish the scenic value of the water body. Because of overfishing within the lake, captive culture of Nile perch can be useful in reducing fishing pressure on the wild stock while providing cheap and high-quality protein to the people around the lake region. Boutique Fish Farms, a research project funded by World Bank and conducted by the University of Jerusalem has sought to establish aquaculture systems for local communities to boost fish supplies in Uganda. Nile perch aquaculture was one of ventures considered by the project (Hebrew University of Jerusalem 2010). Although the results of the project are not explicitly available, it highlights the possibility of captive culture of Nile perch. The results showed that Nile perch can be transported and reared in ponds and cages. Cage aquaculture of Nile perch can be adopted as a measure to reduce pressure on the wild stock occasioned by high exploitation pressure and environmental degradation. There is need for further studies on the ecology, biology and potential of this fish in aquaculture. This article lays a foundation for future research. Notes N.O. Outa* and E.O. Ogello Department of Fisheries and Natural Resources, Maseno University, P.O. Box Private Bag, Maseno, Kenya * Corresponding author: nichouta@gmail.com Tel: +254 723 052 865 This research was funded by the Kenyan Government through GoK research funds to the Kenya Marine and Fisheries Research Institute (KMFRI). References Acerete, L., J. C. Balasch, E. Espinosa, A. Josa and L.Tort. 2004. Physiological responses in Eurasian perch (Perca fluviatilis, L.) subjected to stress by transport and handling. Aquaculture 237:167-178. AOAC (Association of Official Analytical Chemists). 2005. Official Methods of Analysis, 18th Edition, Association of Official Analytical Chemists, Washington DC. USA Bui, T.M., N. Phuong, G. Hien and S. Silva. 2012. Fry and fingerling transportation in the striped cat fish, Pangasianodon hypophthalmus, farming sector, Mekong Delta, Vietnam : A pivotal link in the production chain. Aquaculture 388-391:70-75. Campbell, L.M., R. Hecky and S. Wandera. 2003. Stable isotope analyses of food web structure and fish diet in Napoleon and Winam Gulfs, Lake Victoria, East Africa. Journal of Great Lakes Research 29:243-257. Cowx, I. G., M. van der Knaap, L. Muhoozi and A. Othina. 2003. Improving fishery catch statistics for Lake Victoria. Aquatic Ecosystem Health and Management 3:299-310. Dadebo, E., M. Seyoun and Z. Gebre-Mariam. 2005. Feeding habits of the Nile perch, Lates niloticus (Pisces: Centropomidae) in Lake Chamo, Ethiopia. Ethipoian Journal of Sceince 28:61-68. David, G.S., E. Carvalho, D. Lemos, A. Silveira and M. Agliosobrinho. 2015. Ecological carrying capacity for intensive tilapia (Oreochromis niloticus) cage aquaculture in a large hydroelectrical reservoir in Southeastern Brazil. Aquacultural Engineering 66:30-40. Degefu, F., S. Mengistu and M. Schagerl. 2011. Influence of fish cage farming on water quality and plankton in fish ponds: A case study in the Rift Valley and North Shoa reservoirs, Ethiopia. Aquaculture 316:129-135. FAO (Food and Agriculture Organization of the United Nations). 2007. Cage aquaculture; regional reviews and global overview. Fisheries Technical Paper 1–124. Rome, Italy. Goudswaard, K., F. Witte and E. Katunzi. 2008. The invasion of an introduced predator, Nile perch (Lates niloticus, L.) in Lake Victoria (East Africa): Chronology and causes. Environmental Biology of Fishes 81:127-139. Gregory, R. G. 2006. The Nile perch Lates niloticus: A potential candidate for cage aquaculture. In M. Halwart and J.F Moehl (eds). FAO Regional Technical Expert Workshop on Cage Culure Culture in Afrca Enebbe, Uganda, 20-23 October 2004. FAO Fisheries Proceedings No. 6. Rome FAO, 111. Hallare, A., P. Factor, E. Santos and H. Hollert. 2009. Assessing the impact of fish cage culture on Taal Lake (Philippines) water and sediment quality using the Zebrafish Embryo Assay. Phillipine Journal of Science 138:91-104. Hebrew University of Jerusalem. 2010. “Boutique” fish farms created for Ugandans to combat Lake Victoria’s depleted fish supplies. ScienceDaily. Retrieved November 13, 2018 from www.sciencedaily.com/releases/2010/02/100208144629.htm (Vol. XXXIII). Huchette, S.M.H. and M. Beveridge. 2003. Technical and economical evaluation of periphyton-based cage culture of tilapia (Oreochromis niloticus) in tropical freshwater cages. Aquaculture 218:219-234. Kigbu, A.A., T. Imgbia and M. Yakubu. 2014. Unconventional cultivable freshwater fish species: a potential tool for increased aquaculture production in. Global Journal of Fisheries and Aquaculture 2:152-157. Kishe-Machumu, M.A., F. Witte, H. Wanink and E. Katunzi. 2012. The diet of Nile Perch, Lates niloticus (L.) after resurgence of haplochromine cichlids in the Mwanza Gulf of
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