Scientists from Texas traveled to Tanzania in 1974-1975 to investigate the introduction potential of Lates spp. into Texas reservoirs (Thompson et al. 1977). Temperature tolerance and trophic dynamics were studied for three species (L. angustifrons, L. microlepis and L. mariae). Subsequently, several individuals of these three species were shipped to Heart of the Hills Research Station (HOHRS) in Ingram, Texas in 1975 (Rutledge and Lyons 1976). Also in 1975, Nile perch (L. niloticus) were transferred from Lake Turkana, Kenya, to HOHRS. All fishes were held in indoor, closed-circulating systems (Rutledge and Lyons 1976).
From 1978 to 1985, Lates spp. were released into various Texas reservoirs (Howells and Garrett 1992). Almost 70,000 Lates sp. larvae were stocked into Victor Braunig (Bexar Co.), Coleto Creek (Goliad Co.) and Fairfield (Freestone Co.) reservoirs between 1978 and 1984. In 1985, two L. angustifrons, six L. mariae and six L. niloticus were released into Smithers Reservoir (Ft. Bend Co.). It was thought that the fishes would provide good sportfishing opportunities as well as reduce populations of "rough" fishes (e.g., Cyprinus carpio, Dorosoma cepedianum, Ictiobus bubalis, Carpiodes carpio) through predation (Thompson et al. 1977). It is thought that the introductions were relatively unsuccessful and that the introduced Lates spp. have since been extirpated (Howells and Garrett 1992; Clugston 1990; Texas Parks and Wildlife News 1993).
One individual (115.5 cm, 27.2 kg) was collected from Smithers Reservoir in January 1990 (Howells and Garrett 1992). It is believed that this fish died due to cold water temperatures
Ecology: The species inhabits a wide variety of habitats, including rivers, lakes, irrigation channels. It is relatively intolerant of low-oxygen waters, and therefore is somewhat restricted from entering swamps (Schofield and Chapman 2000).
Juvenile Nile perch feed on invertebrates (e.g., ephemeropteran naiads, anisopterans, zygopterans and chironomids) when small then switch to fishes with growth (Schofield and Chapman 1999). When fish prey is abundant, the Nile perch is piscivorous from a very small size (as small as 4 cm TL; Schofield and Chapman, unpublished data). The species is flexible in its feeding habits, and quickly adapts to new prey resources (Ogari and Dadzie 1988; Chapman et al. 2003).
Lower lethal temperatures have been reported from 12-15 ºC (Midgley 1968; Hopson 1972; Jensen 1975 -- All from Rutledge and Lyons 1976).
The Nile perch reaches maturity at about 60-90 cm TL.
Impact of Introduction: Unknown in Texas.
The introduction of the Nile perch into the Lake Victoria basin has caused the extinction of at least 200 species of endemic fishes and significant changes in the trophic function and diversity of the lake (Ogutu-Ohwayo 1990, Kaufman 1992; Witte et al. 1992). Cascading effects of these losses of native fish diversity and abundance have also occurred, such as algal blooms and insect outbreaks. Similar to Lake Victoria, declines in native fish diversity and distribution have occurred in other lakes with the introduction of Nile perch (e.g., Lake Kyoga basin, Mbabazi et al. 2004).
The Nile perch hosts a number of parasites, including helminths, cestodes, acanthocephalans and myxozoans (Emere 2000; Kostoingue et al. 2003).
References: (click for full references)
Abila, R. O. 1998. The patterns and trends of marketing and consumption of the fish of Lake Victoria (Kenyan waters). African Journal of Tropical Hydrobiology and Fisheries 8: 35-40.
Chapman, L. J., C. A. Chapman, P. J. Schofield, J. P. Olowo, L. S. Kaufman, O. Seehausen & R. Ogutu-Ohwayo. 2003. Fish faunal resurgence in Lake Nabugabo, East Africa. Conservation Biology 17(2): 500-511.
Emere, M. C. 2000. Parasitic infection of the Nile perch Lates niloticus (L.) in River Kaduna. Journal of Aquatic Sciences 15: 51-54.
Eschmeyer, W. N., C. J. Ferraris, Jr., M. D. Hoang and D. J. Long. 1998. A Catalogue of the Species of Fishes. Preliminary Version 2, November 1996. California Academy of Sciences. Available online at: http://www.calacademy.org/research/ichthyology/species/.
Froese, R. and D. Pauly. Editors. 2005. FishBase. http://www.fishbase.org.
Howells, R. G. 1992. Guide to identification of harmful and potentially harmful fishes, shellfishes and aquatic plants prohibited in Texas. Texas Parks and Wildlife Department Special Publication.
Howells, R. G. and G. P. Garrett. 1992. Status of some exotic sport fishes in Texas waters. Texas Journal of Science 44: 317-324.
Kaufman, L. 1992. Catastrophic change in species-rich freshwater ecosystems: the lessons of Lake Victoria. Bioscience 42: 846-858.
Kostoingue, B., M. Fall, C. Diebakate, N. Faye and B. S. Toguebaye. 2003. Light and electronic observations on Henneguya ghaffari (Myxosporea, Bivalvulida) infecting the gills and intestine of Nile perch Lates niloticus (Pisces: Teleostei) from Chad and Senegal. Diseases of Aquatic Organisms 54: 79-83.
Mbabazi, D., R. Ogutu-Ohwayo, S. B. Wandera and Y. Kiziito. 2004. Fish species and trophic diversity of haplochromine cichlids in the Kyoga satellite lakes (Uganda). African Journal of Ecology 42: 59-68.
Ogari, J. and S. Dadzie. 1988. The food of the Nile perch, Lates niloticus (L.), after the disappearance of the haplochromine cichlids in the Nyanza Gulf of Lake Victoria (Kenya). Journal of Fish Biology 32: 571-577.
Ogutu-Ohwayo, R. 2004. Management of the Nile perch, Lates niloticus fishery in Lake Victoria in light of the changes in its life history characteristics. African Journal of Ecology 42: 306-314.
Rutledge, W. P. and B. W. Lyons. 1976. Texas peacock bass and Nile perch: status report. Thirtieth Annual Conference, Southeastern Association of Game and Fish Commissioners.
Schofield, P. J. and L. J. Chapman. 1999. Interactions between Nile perch, Lates niloticus, and other fishes in Lake Nabugabo, Uganda. Environmental Biology of Fishes 55: 343-358.
Schofield, P. J. and L. J. Chapman. 2000. Hypoxia tolerance of introduced Nile perch: implications for survival of indigenous fishes in the Lake Victoria basin. African Zoology 38: 35-42.
Thompson, K. W., C. Hubbs and B. W. Lyons. 1977. Analysis of potential environmental factors, especially thermal, which would influence the survivorship of exotic Nile perch if introduced into artificially heated reservoirs in Texas. Texas Parks and Wildlife Department Technical Series No. 22.37 pp.
Witte, F., T. Goldschmidt, P. C. Goudswaard, W. Ligtveoet, M. J. P. van Oijen and J. H. Wanink. 1992. Species extinction and concomitant ecological changes in Lake Victoria. Netherlands Journal of Zoology 42: 214-232.
This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.