, Volume 40, Issue 5, pp 469–478 | Cite as

Management Implications of the Response of Two Tilapiine Cichlids to Long-Term Changes in Lake Level, Allodiversity and Exploitation in an Equatorial Lake

  • Dalmas Oyugi Oyugi
  • David Matthew Harper
  • Japheth Michemi Ntiba
  • Seth Marande Kisia
  • John Robert Britton


The tilapiine cichlids Oreochromis leucostictus and Tilapia zillii were introduced into Lake Naivasha, Kenya, in 1956. Previous studies on data collected to 1987 revealed they were persistent following establishment, despite environmental variability and exploitation. Recent data, however, suggest this persistence is under threat as data indicate some significant declines in aspects of their abundance since 1999. The influence of changes in lake level, allodiversity and fishing effort on this decline was tested and showed that a decline in lake level was a significant causal factor. The recent change in allodiversity, with the establishment and dominance of Cyprinus carpio in the fishery, was not significant on the catch per unit effort of O. leucostictus but was on T. zillii. Since 1999, catches of tilapiines in the fishery have been independent of fishing effort, contrary to between 1975 and 1987, suggesting their management through application of fishery models may no longer be applicable. As it was anthropogenic-mediated lake level changes that were mainly responsible for their decline, then lake management should focus on sustainable water utilization that maximizes lake levels in accordance with the basin-wide water balance.


Oreochromis leucostictus Tilapia zillii Catch per unit effort Fishery catch Environmental change 



This work was conducted under the Kenya Government Research Permit NCST 5/002/R/020-D to D. M. Harper and was undertaken with strong support from the Fisheries Department, the Kenya Marine and Fisheries Research Institute and the Water Resources Management Authority. Our appreciation is also due to The British Council for a Commonwealth Scholarship award to D. Oyugi to facilitate part of this work. Sponsors of funding also include the Earthwatch Institute (to 2007), the Darwin Initiative (logistical support of vehicles) and the British Council DelPHE project “Field IT” (2009-11). The authors would also like to sincerely thank Vincent I. Kinyua and George N. Morara for providing fishery data, Dominic Wambua for lake level data, George E. Owiti for laboratory working space and the entire “Lakes, Wetlands and People of East Africa’s Rift Valley” field team for their support in the sampling expeditions.


  1. Becht, R., and D.M. Harper. 2002. Towards understanding the human impact upon the hydrology of Lake Naivasha, Kenya. Hydrobiologia 488: 1–11.CrossRefGoogle Scholar
  2. Beveridge, M.C.M., and B.J. McAndrew. 2000. Tilapia: Biology and exploitations. Fish and Fisheries Series 25, 505 pp. Dordrecht: Kluwer Academic.Google Scholar
  3. Britton, J.R., D.M. Harper, and D.O. Oyugi. 2010. Is the fast growth of the introduced Micropterus salmoides in an equatorial lake explained by high water temperatures? Ecology of Freshwater Fish. doi: 10.1111/j.1600-0633.2010.00407.x.
  4. Britton, J.R., R.R. Boar, J. Grey, J. Foster, J. Lugonzo, and D.M. Harper. 2007. From introduction to fishery dominance: The initial impact of the invasive carp Cyprinus carpio in Lake Naivasha, Kenya, 1999 to 2006. Journal of Fish Biology 71: 239–257.CrossRefGoogle Scholar
  5. Britton, J.R., and D.M. Harper. 2008. Juvenile growth of two tilapia species in Lakes Naivasha and Baringo, Kenya. Ecology of Freshwater Fish 17: 481–488.CrossRefGoogle Scholar
  6. Britton, J.R., M.C. Jackson, S.M. Muchiri, H. Tarras-Wahlberg, D.M. Harper, and J. Grey. 2009. Status, ecology and conservation of an endemic fish, Oreochromis niloticus baringoenesis, in Lake Baringo, Kenya. Aquatic Conservation: Marine and Freshwater Ecosystems 19: 487–496.CrossRefGoogle Scholar
  7. Bwanika, G.N., B. Makanga, Y. Kizito, L.J. Chapman, and J. Balirwa. 2004. Observations on the biology of Nile tilapia Oreochromis niloticus L., in two Ugandan crater lakes. African Journal of Ecology 42: 93–101.CrossRefGoogle Scholar
  8. Coward, K., and N.R. Bromage. 1999. Spawning frequency, fecundity, egg size and ovarian histology in groups of Tilapia zillii maintained upon two distinct food ration sizes from first-feeding to sexual maturity. Aquatic Living Resources 12: 11–22.CrossRefGoogle Scholar
  9. De Silva, S.S. 1985. Observations on the abundance of the exotic cichlid Sarotherodon mossambicus (Peters) in relation to fluctuations in the water-level in a man-made lake in Sri Lanka. Aquaculture and Fisheries Management 16: 265–272.Google Scholar
  10. Dudley, R.G. 1975. Growth of Tilapia of the Kafue floodplain Zambia: Predicted effects of the Kafue Gorge Dam. Transactions of the American Fisheries Society 103: 281–291.CrossRefGoogle Scholar
  11. Dudley, R.G. 1979. Changes in the growth and size distribution of Sarotherodon macrochir and Sarotherodon andersonii from the Kafue floodplain, Zambia, since construction of the Kafue Gorge Dam. Journal of Fish Biology 14: 205–223.CrossRefGoogle Scholar
  12. Duponchelle, F., and J. Panfili. 1998. Variation in age and size at maturity in female Nile tilapia, Oreochromis niloticus, population from man-made lake of Côte d’Ivoire. Environmental Biology of Fishes 52: 453–465.CrossRefGoogle Scholar
  13. Duponchelle, F., P. Cecchi, D. Corbin, J. Nunez, and M. Lendre. 2000. Variation in fecundity and egg size of female Nile tilapia, Oreochromis niloticus, from man-made lakes of Côte d’Ivoire. Environmental Biology of Fishes 57: 155–170.CrossRefGoogle Scholar
  14. Fryer, G., and T.D. Iles. 1972. The cichlid fishes of the Great Lakes of Africa: Their biology and evolution. Edinburgh: Oliver and Boyd. 641 pp.Google Scholar
  15. Guenther, M., and R. Bozelli. 2004. Effects of inorganic turbidity on the phytoplankton of an Amazonian lake impacted by bauxite tailings. Hydrobiologia 511: 151–159.CrossRefGoogle Scholar
  16. Harper, D.M., and K.M. Mavuti. 2004. Lake Naivasha, Kenya: Ecohydrology to guide the management of a tropical protected area. Ecohydrology and Hydrobiology 4: 287–305.Google Scholar
  17. Hickley, P., and D.M. Harper. 2002. Fish community and habitat changes in artificially stocked fishery of Lake Naivasha, Kenya. In Management and ecology of lake and reservoir fisheries, ed. I.G. Cowx, 242–254. Oxford: Blackwell Scientific Publications.Google Scholar
  18. Hickley, P., R. Bailey, D.M. Harper, R. Kundu, S.M. Muchiri, R. North, and A. Taylor. 2002. The status and future of the Lake Naivasha fishery, Kenya. Hydrobiologia 488: 181–190.CrossRefGoogle Scholar
  19. Hickley, P., M. Muchiri, R.R. Boar, J.R. Britton, C. Adams, N. Gichuru, and D.M. Harper. 2004. Habitat degradation and subsequent fishery collapse in Lakes Naivasha and Baringo, Kenya. Ecohydrology and Hydrobiology 4: 503–517.Google Scholar
  20. Hickley, P., M. Muchiri, J.R. Britton, and R.R. Boar. 2008. Economic gain versus ecological damage from the introduction of non-native freshwater fish: Case studies from Kenya. Open Fish Science Journal 1: 36–46.CrossRefGoogle Scholar
  21. Jul-Larsen, E., J. Kolding, J.R. Nielsen, R. Overa, and P.A.M. van Zwieten. 2003. Management, co-management or no management? Major dilemmas in southern African freshwater fisheries. Part 1. Synthesis report. FAO Fisheries Technical Paper No. 426/1. Rome: FAO.Google Scholar
  22. Kitaka, N., D.M. Harper, and K.M. Mavuti. 2002. Phosphorus inputs to Lake Naivasha, Kenya, from its catchment and the trophic state of the lake. Hydrobiologia 488: 73–80.CrossRefGoogle Scholar
  23. Koehn, J. 2004. Carp (Cyrpinus carpio) as a powerful invader in Australian waterways. Freshwater Biology 49: 882–894.CrossRefGoogle Scholar
  24. Kolding, J. 1993. Population dynamics and life history styles of Nile Tilapia, Oreochromis niloticus, in Ferguson’s Gulf, Lake Turkana, Kenya. Environmental Biology of Fishes 37: 25–46.CrossRefGoogle Scholar
  25. Kolding, J., and P.A.M. van Zwieten. 2006. Improving productivity in tropical lakes and reservoirs. Challenge program on water and food. Aquatic ecosystems and fisheries review series 1, 139 pp. Theme 3 of CPWF, C/o WorldFish Center, Cairo, Egypt, ISBN: 977-17-3087-8.Google Scholar
  26. Lappalainen, J., A. Serhan Tarkan, and C. Harrod. 2008. A meta-analysis of latitudinal variations in life-history traits of roach, Rutilus rutilus, over its geographical range: Linear or non-linear relationships? Freshwater Biology 53: 1491–1501.CrossRefGoogle Scholar
  27. Lowe-McConnell, R.H. 1982. Tilapias in fish communities. In The biology and culture of tilapias, eds. R.S.V Pullin and R.H. McConnell, 83–113. ICLARM conference proceedings 7. International Center for living Aquatic Resources Management, Manila.Google Scholar
  28. McKaye, K.R., J.R. Ryan, J.R. Stauffer, L.J. Lopez Perez, G.I. Vega, and E.P. van den Berghe. 1995. African tilapia in Lake Nicaragua: Ecosystem in transition. BioScience 45: 406–411.CrossRefGoogle Scholar
  29. Muchiri, S.M., P. Hickley, D.M. Harper, and R. North. 1994. The potential for enhancing the fishery of Lake Naivasha, Kenya. In Rehabilitation of freshwater fisheries, ed. I.G. Cowx, 348–357. Oxford: Fishing News Book/Blackwell Science.Google Scholar
  30. Muchiri, S.M., P.J.B. Hart, and D.M. Harper. 1995. The persistence of two introduced tilapia species in Lake Naivasha Kenya in the face of environmental variability and fishing pressure. In The impact of species changes in African lakes, eds. T.J. Pitcher and P.J.B. Hart, 299–320. London: Chapman & Hall.Google Scholar
  31. Njiru, M., J.B. Okeyo-Owuor, S.M. Muchiri, and I.G. Cowx. 2004. Shifts in the food of Nile tilapia, Oreochromis niloticus (L.) in Lake Victoria, Kenya. African Journal of Ecology 42: 163–170.CrossRefGoogle Scholar
  32. Peterson, M.S., W.T. Slack, N.J. Brown-Petersen, and J.L. McDonald. 2004. Reproduction in non native environments: establishment of Nile tilapia, Oreochromis niloticus, in Coastal Mississippi watersheds. Copeia 2004: 842–849.CrossRefGoogle Scholar
  33. Peterson, M.S., W.T. Slack, and C.M. Woodley. 2005. The occurrence of non-indigenous Nile tilapia, Oreochromis niloticus (Linnaeus) in coastal Mississippi, USA: Ties to aquaculture and thermal effluent. Wetlands 25: 112–121.CrossRefGoogle Scholar
  34. Siddiqui, A.Q. 1977. Lake Naivasha fishery, Kenya, and its management together with a note on feeding habits of fishes. Conservation Biology 12: 217–227.CrossRefGoogle Scholar
  35. Weyl, O. 2007. Rapid invasion of a subtropical lake fishery in central Mozambique by Nile Tilapia Oreochromis niloticus (Pisces: Cichlidae). Aquatic Conservation: Marine and Freshwater Ecosystems 18: 839–851.CrossRefGoogle Scholar
  36. Wootton, R.J. 1984. Introduction: Strategies and tactics in fish reproduction. In Fish reproduction: Strategies and tactics, eds. G.W. Potts and R.J. Wootton, 1–12. London: Academic Press.Google Scholar
  37. Zalewski, M., G.A. Janauer, and G. Jolankaj. 1997. Ecohydrology: A new paradigm for the sustainable use of aquatic resources. Conceptual Background, Working Hypotheses, Rationale and Scientific Guidelines for the Implementation of the IHP-V Projects 2.3/2.4. International Hydrological Programme UNESCO. Paris Technical Documents on Ecohydrology No. 7.Google Scholar

Copyright information

© Royal Swedish Academy of Sciences 2011

Authors and Affiliations

  • Dalmas Oyugi Oyugi
    • 1
    • 2
  • David Matthew Harper
    • 3
  • Japheth Michemi Ntiba
    • 1
  • Seth Marande Kisia
    • 4
  • John Robert Britton
    • 2
  1. 1.School of Biological SciencesUniversity of NairobiNairobiKenya
  2. 2.Centre for Conservation Ecology and Environmental Science, School of Applied SciencesBournemouth UniversityPoole, DorsetUK
  3. 3.Department of BiologyUniversity of LeicesterLeicesterUK
  4. 4.School of Veterinary MedicineUniversity of NairobiNairobiKenya

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