Skip to main content

Management of the Nile tilapia (Oreochromis niloticus (L.)) fishery in the Kenyan portion of Lake Victoria, in light of changes in its life history and ecology

Buy Article:

$43.00 plus tax (Refund Policy)


This study reports on the population parameters, catch distribution and feeding ecology of Nile tilapia (Oreochromis niloticus) from bottom trawls and commercial catches obtained in the Kenyan portion of Lake Victoria during 1997–2006. The population parameters were analysed using the FAO-ICLARM stock assessment tool (FISAT). The fish biomass and the food ingested by the fish were estimated using the swept area and point methods, respectively. Immature fish comprised ≈70% of the total fish population. The asymptotic length, maximum weight, maximum age, exploitation rate (E) and length at 50% maturity of Nile tilapia have decreased, whereas the growth curvature and fishing mortality have increased. The commercial catches increased from 13.93 t in 1997, to 23.70 t in 1999, decreasing thereafter to 18.73 t in 2005. The bottom trawl catches increased from 46.90 kg ha−1 in 1997, to 401.48 kg ha−1 in 2000, decreasing thereafter to 15.57 kg ha−1 in 2006. The major food items ingested by the fish were algae, insects and other fish. Population parameters, and the catch and diet of O. niloticus, have changed over the years in Lake Victoria. The population characteristics suggest a population under stress, attributable to intense catch exploitation. Even under intense exploitation (E = 0.68), however, the mature fish constituted ≈30% of the population. The commercial catches are still high, indicating a very resilient fishery. Nevertheless, despite this resilience, the future of Oreochromis fishery is threatened by increased fishing capacity in the lake, and there is need to re-evaluate the effectiveness of current fishery management measures, with the goal of possibly adopting new measures. Enactment of new fishery policies also should provide for co-management to enhance the management process. Furthermore, there is a need to reduce fishing capacity and illegal fishing methods, and to seek alternative livelihoods for lake fishers and other stakeholders.
No References
No Citations
No Supplementary Data
No Article Media
No Metrics

Keywords: co-management; diet; overfishing; population parameters

Document Type: Research Article

Affiliations: 1: Kenya Marine and Fisheries Research Institute, PO Box 1881, Kisumu, Kenya, 2: Department of Fisheries and Aquatic Sciences, Moi University, PO Box 1125, Eldoret, Kenya, 3: PO Box 43, AA 6700AA, Waginengen, The Netherlands

Publication date: 2008-06-01

  • Access Key
  • Free content
  • Partial Free content
  • New content
  • Open access content
  • Partial Open access content
  • Subscribed content
  • Partial Subscribed content
  • Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more