Nile Perch

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The Nile Perch: Friend or Foe for Lake Victoria INTRODUCTION: An alien species is a species introduced outside its normal distribution. It is clear that alien species can be both beneficial, for example the honey bee, pollinating many of the countries important crops and fruit. However it is more frequently seen that alien species have a negative effect on the habitat. The alien species under discussion in this essay is the Nile Perch. The Nile Perch is seen throughout much of the Afrotropic ecozone, as well as being native to the Nile, Senegal, Congo, Volta, Niger, Lake Turkana, and Lake Chad. The Nile Perch was introduced manually into Lake Victoria in the late 1950s and early 1960s. Lake Victoria covers a total of 69,000 square kilometres,…show more content…
In the 1970s it began to colonise the rich, fertile, multispecies fishing areas of the Nyanza Gulf in Kenya, it was here that in the next 10 years the Nile Perch became a major component of the fish population. Until the late 1970s the biomass composition of the lake remained relatively constant, but in the middle 1980s, a survey of the lake revealed a sudden and unexpected change, a total reverse in biomass compositions. Cichlid numbers had decreased dramatically and only consisted of 1% of the total fish weight in the lake, while the Nile Perch had suddenly increased to constitute 80%. This large increase in numbers of the Nile Perch may have been caused due to the advantages it may have had over other fish in the lake. The Nile perch is a dominating predatory fish within the Lake. The Nile Perch can inhibit both tropical and fresh water. They become sexually mature at the age of three years and reproduce in large numbers (they can produce 16 million eggs at one time) with juveniles requiring no parental…show more content…
Ogari 1988.Growth and mortality rates of the Nile Perch. FAO fisheries report,389:272-287 FishBase, 2004. "Lates niloticus, Nile perch" Kitchel, J., D. Schindler. 1997. The Nile perch in Lake Victoria: Interactions between predation and fisheries. Ecological Applications, 7 (2): 653-664. Ogutu-Ohwayo, R. 1984. The Effects of Predation by Nile Perch, *Lates niloticus* (Linne) Introduced into Lake Kyoga (Uganda) in Relation to the Fisheries of Lake Kyoga and Lake Victoria. FAO Fisheries Report, 335: 18-41. Ogari, J. 1984. Distribution, Food and Feeding Habits of *Lates niloticus* in Nyanza Gulf of Lake Victoria (Kenya). FAO Fisheries Report, 335: 68-80. Schofield, P. 1999. Interactions between Nile perch, *Lates niloticus*, and other fishes in Lake Nabugabo, Uganda. Environmental Biology of Fishes, 55 (4): 343-358. Verschuren, D., T. Johnson. 2002. History and timing of human impact on Lake Victoria, East Africa. Proceedings of the Royal Society Biological Sciences Series B, 269 (1488): 289-294. Queensland Department of Primary Industries and Fisheries, 2004. "Fish - Note, Nile Perch (Lates niloticus)" Goudswaard, P., F. Witte. 1984. Observation on Nile perch, *Lates niloticus* (L.), 1758, in the Tanzanian waters of Lake Victoria. FAO Fisheries Report, 335:

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