| Nile perch | |
|---|---|
 | |
| Lates niloticus | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Carangiformes |
| Suborder: | Centropomoidei |
| Family: | Latidae |
| Genus: | Lates |
| Species: | L. niloticus |
| Binomial name | |
| Lates niloticus | |
| Synonyms | |
| |
TheNile perch (Lates niloticus), also known as theAfrican snook,Goliath perch,African barramundi,Goliath barramundi,Giant lates or theVictoria perch, is aspecies offreshwater fish in familyLatidae of orderPerciformes. It is widespread throughout much of theAfrotropical realm, being native to theCongo,Nile,Senegal,Niger andLake Chad,Volta,Lake Turkana, and other river basins. It also occurs in thebrackish waters ofLake Maryut inEgypt. The Nile perch is a fish of substantial economic and food-security importance in East Africa.[3] Originally described asLabrus niloticus, among the marinewrasses, the species has also been referred to asCentropomus niloticus. Common names include African snook, Victoria perch (a misleading trade name, as the species is not native toLake Victoria, though they have been introduced there), and many local names in various African languages, such as theLuo namembuta ormputa. InTanzania, it is calledsangara,sankara, orchenku. In Francophone African countries, it is known ascapitaine. Its name in theHausa language isgiwan ruwa, meaning "water elephant".
L. niloticus is silver in color with a blue tinge. It has distinctive dark-black eyes, with a bright-yellow outer ring. One of the largestfreshwater fishes, it reaches a maximum length of nearly 2 m (6 ft 7 in), weighing up to 200 kg (440 lb).[4] Mature fish typically range from 1.21–1.37 m (4 ft 0 in – 4 ft 6 in), although many fish are caught before they can grow this large.[5]
Adult Nile perch occupy all habitats of a lake with sufficientoxygen concentrations, while juveniles are restricted to shallow or nearshore environments. A fiercepredator that dominates its surroundings, the Nile perch feeds on fish (including its own species),crustaceans,molluscs, andinsects; the juveniles also feed onzooplankton.[6] Nile perch useschooling as a mechanism to protect themselves from other predators.[7][8]
Nile perch have been introduced to many other lakes in Africa, including Lake Victoria and the artificialLake Nasser. TheWorld Conservation Union's Invasive Species Specialist Group considersL. niloticus one of the world's 100 worst invasive species.[9]
The state ofQueensland in Australia levies heavy fines on anyone found in possession of a living Nile perch, since it competes directly with the nativebarramundi, which is similar and grows to 1.5 m (4 ft 11 in) long, while the Nile perch grows to 2.0 m (6 ft 7 in) long.[10]
The species is of great commercial importance as a food fish. The Nile perch is also popular with sportanglers, as it attacks artificialfishing lures, and it is also raised inaquaculture.[11]
 | This sectionneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources in this section. Unsourced material may be challenged and removed.(January 2021) (Learn how and when to remove this message) |
The introduction of this species to Lake Victoria is one of the most cited examples of the negative effects alien species can have on ecosystems.[13]
The Nile perch wasintroduced to Lake Victoria in East Africa in the 1950s,[14][15] and has since been fished commercially. In 2003, Nile perch sales to the EU reached 169 million euros. Sport-fishing in the region of Uganda and Tanzania provided additional income from tourism.
Its introduction was ecologically disruptive and is attributed with causing the extinction or near-extinction of several hundred native species, with some populations fluctuating withcommercial fishing and the actual Nile perch stocks. The Nile perch initially fed on native cichlids, but with decreasing availability of this prey, it now consumes mainly smallshrimp andminnows.
The alteration of the native ecosystem had disruptive socioeconomic effects on local communities bordering the lake. Many local people have been displaced from their traditional occupations in the fishing trade and brought them into the cash economy, or before the establishment of export-oriented fisheries, turned them intoeconomic refugees. At least initially, nets strong enough to hold adult Nile perch could not be manufactured locally and had to be imported for a high price.[16]
The introduction of Nile perch has also had additional ecological effects on shore. Native cichlids were traditionally sun-dried, but because Nile perch have a high fat content (higher than cichlids), they need to be smoked to avoid spoiling. This has led to an increased demand for firewood in a region already hard-hit bydeforestation,soil erosion, anddesertification.
TheAcademy Award-nominated documentaryDarwin's Nightmare byHubert Sauper (a French-Austrian-Belgian production, 2004) deals with the damage that has been caused by Nile perch introduction, including the import of weapons and ammunition in cargo planes from Europe, which are then used to export Nile perch, further exacerbating conflict and misery in the surrounding regions.[17]
Regardless of whether it is considered positive or negative,[18] thetrophic web of Lake Victoria appears to have been drastically impoverished by the introduction of this novel near-top-level predator. While the ecosystem seems to be moving towards a new equilibrium, neither its former state nor the state of fisheries on Lake Victoria can ever easily be brought back.[19][20][21]
Despite being a successful invasive species, the fish faces threats. Being a species ofmegafauna, the most obvious threats to the species are overfishing and the use ofillegal fishing gear, as well as invasivewater hyacinths. Prey depletion is also a factor, as it decreases the size of the fish and makes it vulnerable to larger predators, such as crocodiles.[citation needed]
In 2021, The Uganda Fish Processors and Exporters Association called on the parliament to ban the local consumption of the species so as to protect its export.[22]
Nile perch were involved with the worship ofNeith.[23] As a result nile perch were sometimes mummified.[23] A deposit of several thousand mummified perch was excavated in an area to the west ofEsna where there was a temple to Neith.[24] Mummified perch have also been found atGurob near a temple to Neith while perch statuettes have been found atSais again in the context of a temple to Neith.[24]
