Taxonomic name: Lates niloticus (Linnaeus 1758)
Synonyms: Lates albertianus Worthington, 1932, Lates niloticus rudolfianus Worthington, 1932, Lates niloticus var. macrolepidota Pellegrin, 1922, Perca latus Geoffroy Saint-Hilaire, 1827
Common names: chengu (Kijitta), mbuta (Kiluo), nijlbaars (Dutch), nilabborre (Swedish), Nilbarsch (German), nile perch (English), perca di nilo (Spanish), perche du nil (French), persico del nilo (Italian), sangara (Kiswahili), Victoria perch (English), victoriabaars (Dutch), victoriabarsch (German)
Organism type: fish The Nile perch (Lates niloticus) is a large freshwater fish. Also known as capitaine, mputa or sangara, it can grow up to 200kg and two metres in length. It was introduced to Lake Victoria in 1954 where it has contributed to the extinction of more than 200 endemic fish species through predation and competition for food. Description
Large perch-like predator. Dorsal fin deeply notched, giving the appearance of two separate fins; the first part completely spinous; third dorsal spine enlarged. Lateral line continuous. Pre-orbital and pre-opercular bones with spines; a large spine on operculum. Occurs in:
lakes, water courses, wetlands Habitat description
Freshwater species, but living in brackish waters in Lake Mariout. Introductions in Lake Victoria were mainly from Lake Albert, but also from Lake Turkana. The present populations in Lake Victoria are apparently not pure Lates niloticus but contain some genetic material from Lates macrophthalmus from Lake Albert. General impacts
The Nile perch is responsible through predation and competition for food for the decimation and possible disappearance of two hundred or more species of the unique flock of endemic haplochromine cichlids in Lake Victoria. Uses
Nile perch took decades to become evident in Lake Victoria and then burst into the huge biomass of the late 1980s and 1990s and the subsequent harvest for
export. It rose to become the main fishery species in the lake in the late 1990s and the basis of a huge export industry. This raised the price of Nile
perch to something beyond the reach of many lakeside communities. All of this was documented in the first two phases of an IUCN-World Conservation Union's
Nile perch project, which culminated in the making of the film "Big fish, small fry". The project has moved on to conflict resolution and capacity building
using "beach units" to give more responsibility and management involvement to local people. This work is supported by the three riparian government fisheries
departments, through the Lake Victoria Fisheries Organisation (LVFO), and is currently being reviewed.
In recent years the Nile perch population has begun to stabilise and the availability of large fish has declined as has the catch which is now way below the
capacity of the factories which process and export the fish to USA, Europe, Australia and New Zealand. The view of the three riparian governments is that
Nile perch is an essential export earner and they have attempted to brand it as "organic", as it is wild and without artificial additives etc.(although cage rearing has begun). This same export has brought some benefits to the local people (in income from fishing and jobs in factories) and
some disbenefits from availability of fish for food and economic and social upheaval (Howard, G., pers. comm., August 2005). Geographical range
Native range: Native to the Nile system, Lake Mariout, and most major West African river systems, from the Senegal to the Cross; also present in the Zaire system and lakes Albert, Turkana and several lakes in the Ethiopian highlands.
Known introduced range: Introduced in Lakes Kyoga, Nabugabo and Victoria in East Africa. Occuring in all depth zones; less abundant in littoral rocky habitats and oxygen-poor conditions. Also reported to be introduced from Sudan to Congo and from Ethiopia to Cuba and possibly established in the wild; also from Mali to Morocco and from Africa to Texas (USA), both apparently without establishing populations in the wild. Introduction pathways to new locations
Landscape/fauna "improvement": Introduced for fisheries purposes.
Local dispersal methods
Natural dispersal (local): Swimming around. Management information
Eradication of the Nile perch in Lake Victoria is impossible in practice, and is also not an option because of its economic success. Nutrition
Large predator, feeding in Lake Victoria on haplochromine cichlids, the zooplanktivorous cyprinid Rastrineobola argentea, the prawn Caridina nilotica and juvenile Nile perch (cannibalism). Young stages feed on invertebrates. Reproduction
Free spawning over shallow sheltered areas, all the year round with peaks in rainy season.
Up to 16 million eggs per breeding cycle. Lifecycle stages
In Lake Victoria, male size at first maturity 50-55cm TL (ca. 2 years), females 67,5-85cm TL (2-4 years). Fifty percent maturity at 60-74cm TL for males and 102-110cm TL for females. Maturity sizes strongly decreasing in recent years. This species has been nominated as among 100 of the "World's Worst" invaders Reviewed by: Dr. Jos Snoeks, Africa Museum, Leuvensesteenweg, Tervuren, Belgium.
Compiled by: Dr. Jos Snoeks, Africa Museum, Leuvensesteenweg, Tervuren, Belgium & IUCN/SSC Invasive Species Specialist Group (ISSG)
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Last Modified: Wednesday, 13 April 2005
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