Advertisement

Environmental Biology of Fishes

, Volume 34, Issue 1, pp 1–28 | Cite as

The destruction of an endemic species flock: quantitative data on the decline of the haplochromine cichlids of Lake Victoria

  • Frans Witte
  • Tijs Goldschmidt
  • Jan Wanink
  • Martien van Oijen
  • Kees Goudswaard
  • Els Witte-Maas
  • Niels Bouton
Article

Synopsis

The Lake Victoria fish fauna included an endemic cichlid flock of more than 300 species. To boost fisheries, Nile perch (Lates sp.) was introduced into the lake in the 1950s. In the early 1980s an explosive increase of this predator was observed. Simultaneously, catches of haplochromines decreased. This paper describes the species composition of haplochromines in a research area in the Mwanza Gulf of Lake Victoria prior to the Nile perch upsurge. The decline of the haplochromines as a group and the decline of the number of species in various habitats in the Mwanza Gulf was monitored between 1979 and 1990. Of the 123+ species originally caught at a series of sampling stations ca. 80 had disappeared from the catches after 1986. In deepwater regions and in sub-littoral regions haplochromine catches decreased to virtually zero after the Nile perch boom. Haplochromines were still caught in the littoral regions where Nile perch densities were lower. However, a considerable decrease of species occurred in these regions too. It is expected that a remnant of the original haplochromine fauna will survive in the littoral region of the lake. Extrapolation of the data of the Mwanza Gulf to the entire lake would imply that approximately 200 of the 300+ endemic haplochromine species have already disappeared, or are threatened with extinction. Although fishing had an impact on the haplochromine stocks, the main cause of their decline was predation by Nile perch. The speed of decline differed between species and appeared to depend on their abundance and size, and on the degree of habitat overlap with Nile perch. Since the Nile perch upsurge, the food web of Lake Victoria has changed considerably and the total yield of the fishery has increased three to four times. Dramatic declines of native species have also been observed in other lakes as a result of the introduction of alien predators. However, such data concern less speciose communities and, in most cases, the actual process of extinction has not been monitored.

Key words

Extinction Food web Cichlidae Nile perch Overfishing Predation Species composition Species introduction Trophic groups 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References cited

  1. Acere, T.O. 1988. The controversy over Nile perch, Lates niloticus, in Lake Victoria, East Africa. Naga, The ICLARM Quarterly 11: 3–5.Google Scholar
  2. Anon. 1987. The cichlid fishes of Lake Victoria - was their obituary premature? pp. 31–32. In: Report on the British Museum (Natural History) 1984–86. Trustees of the British Museum (Natural History), London.Google Scholar
  3. Anon. 1988. Monster fish may be innocent of ecological crimes. New Scientist 1622: 34.Google Scholar
  4. Anon. 1991. Fish's future is a bit of a mouthful. New Scientist 1756: 20.Google Scholar
  5. Arunga, J.O. 1981. A case study of the Lake Victoria Nile Perch Lates niloticus (Mbuta) fishery. pp. 165–184. In: Proceedings of the Workshop of the Kenya Marine and Fisheries Research Institute on Aquatic Resources of Kenya, July 13–19, 1981, Kenya National Academy for the Advancement of Arts and Science, Nairobi.Google Scholar
  6. Balon, E.K. & M.N. Bruton. 1986. Introduction of alien species or why scientific advice is not heeded. Env. Biol. Fish. 16: 225–230.Google Scholar
  7. Barel, C.D.N. 1986. The decline of Lake Victoria's cichlid species flock. Reports of the Haplochromis Ecology Survey Team 46, Zoologisch Laboratorium, University of Leiden, Leiden. 96 pp.Google Scholar
  8. Barel, C.D.N., R. Dorit, P.H. Greenwood, G. Fryer, N. Hughes. P.B.N. Jackson, H. Kanawabe, R.H. Lowe-McConnell, F. Witte & K. Yamaoka. 1985. Destruction of fisheries in Africa's lakes. Nature 315: 19–20.Google Scholar
  9. Barel, C.D.N., W. Ligtvoet, T. Goldschmidt, F. Witte & P.C. Goudswaard. 1991. The haplochromine cichlids in Lake Victoria: an assessment of biological and fisheries interests. pp. 258–279. In: M.H.A. Keenleyside (ed.) Cichlid Fishes: Behaviour, Ecology and Evolution, Chapman and Hall, London.Google Scholar
  10. Barel, C.D.N., M.J.P. van Oijen, F. Witte & E.L.M. Witte-Maas. 1977. An introduction to the taxonomy and morphology of the haplochromine Cichlidae from Lake Victoria. Neth. J. Zool. 27: 333–389.Google Scholar
  11. Bruton. M.N. 1990. The conservation of fishes of Lake Victoria, Africa: an ecological perspective. Env. Biol. Fish. 27: 161–190.Google Scholar
  12. CIFA. 1988. Report of the 4th session of the sub-committee for the development and management of the fisheries in Lake Victoria. Kisumu, Kenya, 6–10 April 1987, FAO Fish. Rep. 388: 1–112.Google Scholar
  13. CIFA. 1990. Report of the 5th session of the sub-committee for the development and management of the fisheries in Lake Victoria. Mwanza, Tanzania, 12–14 September 1989, FAO Fish. Rep. 430: 1–97.Google Scholar
  14. Coulter, G.W., B.R. Allanson, M.N. Bruton, P.H. Greenwood, R.C. Hart, P.B.N. Jackson & A.J. Ribbink. 1986. Unique qualities and special problems of the African Great Lakes. Env. Biol. Fish. 17: 117–118.Google Scholar
  15. Daan, N. 1980. A review of replacement of depleted stocks by other species and the mechanisms underlying such replacement. Rapp. P.-v. Reun. Cons. Int. Explor. Met. 177: 405–421.Google Scholar
  16. Fryer, G. 1960a. Concerning the proposed introduction of Nile perch into Lake Victoria. E. Afr. J. Agric. 25: 267–270.Google Scholar
  17. Fryer, G. 1960b. The feeding mechanism of some atyid prawns of the genus Caridina. Trans. Roy. Soc. Edinb. 64: 217–244.Google Scholar
  18. Fryer, G. & T.D. Iles. 1972. The cichlid fishes of the great lakes of Africa. Oliver & Boyd, Edinburg. 642 pp.Google Scholar
  19. Gee, J.M. 1969. A comparison of certain aspects of the biology of Lates niloticus (Linne) in some East African lakes. Rev. Zool. Bot. Afr. 80: 244–262.Google Scholar
  20. Goldschmidt, T. 1991. Egg mimics in haplochromine cichlids (Pisces, Perciformes) from Lake Victoria. Ethology 88: 177–190.Google Scholar
  21. Goldschmidt, T. & P.C. Goudswaard. 1989. Reproductive strategies in haplochromines (Pisces: Cichlidae) of Lake Victoria. pp. 93–119. In: T. Goldschmidt, An Ecological and Morphological Field Study of the Haplochromine Cichlid Fishes of Lake Victoria, Ph.D. Thesis, Rijksuniversiteit Leiden. LeidenGoogle Scholar
  22. Goldschmidt, T. & F. Witte. 1990. Reproductive strategies of zooplanktivorous haplochromine species (Pisces: Cichlidae) from Lake Victoria before the Nile perch boom. Oikos 58: 356–368.Google Scholar
  23. Goldschmidt, T., F. Witte & J. de Visser. 1990. Ecological segregation in zooplanktivorous haplochromine species (Pisces: Cichlidae) from Lake Victoria. Oikos 58: 343–355.Google Scholar
  24. Goudswaard, P.C. 1988. A comparison of trawl surveys in 1969/70 and 1984/85 in the Tanzanian part of Lake Victoria. pp. 86–100. In: CIFA, Report of the 4th Session of the Subcommittee for the Development and Management of the Fisheries in Lake Victoria, Kisumu, Kenya, 6–10 April 1987, FAO Fish. Rep. 388.Google Scholar
  25. Goudswaard, P.C. & W. Ligtvoet. 1988. Recent developments in the fishery for haplochromines (Pisces: Cichlidae) and Nile perch (L.) (Pisces: Centropomidae) in Lake Victoria. pp. 101–112. In: CIFA, Report of the 4th Session of the Subcommittee for the Development and Management of the Fisheries in Lake Victoria, Kisumu, Kenya, 6–10 April 1987, FAO Fish. Rep. 388.Google Scholar
  26. Goudswaard, P.C. & F. Witte. 1985. Observations on Nile perch — Lates niloticus (L.) 1758 — in the Tanzanian waters of Lake Victoria. pp. 62–67. In: CIFA, Report of the 3rd Session of the Sub-committee for the Development and Management of the Fisheries in Lake Victoria, Jinja, Uganda, 4–5 October 1984, FAO Fish. Rep. 335.Google Scholar
  27. Greboval, D. 1990. Socio-economic issues for planning in support of fisheries management. pp. 75–97. In: CIFA, Report of the 5th Session of the Sub-committee for the Development and Management of the Fisheries in Lake Victoria, Mwanza, Tanzania, 12–14 September 1989, FAO Fish. Rep. 430.Google Scholar
  28. Greenwood, P.H. 1959. The monotypic genera of cichlid fishes in Lake Victoria, Part 2. Bull. Br. Mus. Nat. Hist. (Zool.) 5: 165–177.Google Scholar
  29. Greenwood, P.H. 1962. A revision of the Lake Victoria Haplochromis species (Pisces, Cichlidae), Part 5. Bull. Br. Mus. Nat. Hist. (Zool.) 9: 139–214.Google Scholar
  30. Greenwood, P.H. 1965. Environmental effects on the pharyngeal mill of a cichlid fish Astatoreochromis alluaudi and their taxonomic implications. Proc. Linn. Soc. Lond. 176: 1–10.Google Scholar
  31. Greenwood, P.H. 1974. The cichlid fishes of Lake Victoria East Africa: the biology and evolution of a species flock. Bull. Br. Mus. Nat. Hist. (Zool.) Suppl. 6: 1–134.Google Scholar
  32. Greenwood, P.H. 1981. The haplochromine fishes of the East African lakes. Collected papers on their taxonomy, biology and evolution. Kraus International Publications, Munich. 839 pp.Google Scholar
  33. Greenwood, P.H. 1984. African cichlids and evolutionary theories. pp. 141–154. In: A.A. Echelle & I. Kornfield (ed.) Evolution of Fish Species Flocks, University of Maine at Orono Press, Orono.Google Scholar
  34. Hamblyn, E.L. 1961. The Nile perch project. EAFFRO Ann. Rep. 1960: 26–32.Google Scholar
  35. Hamblyn, E.L. 1966. The food and feeding habits of Nile perch: Lates niloticus (Linne) (Pisces: Centropomidae). Rev. Zool. Bot. Afr. 74: 1–28.Google Scholar
  36. Harrison, K. 1991. The taxonomy of East African Nile perch, Lates spp. (Perciformes, Centropomidae). J. Fish Biol. 38: 175–186.Google Scholar
  37. Harrison, K., O. Crimmen, R. Travers, J. Maikweki & D. Mutoro. 1989. Balancing the scales in Lake Victoria. Biologist 36: 189–191.Google Scholar
  38. Hoogerhoud, R.J.C. 1986. Taxonomic and ecological aspects of morphological plasticity in molluscivorous haplochromines (Pisces, Cichlidae). Ann. Mus. Roy. Aft. Centr. Sc. Zool. 251: 131–134.Google Scholar
  39. Hoogerhoud, R.J.C., F. Witte & C.D.N. Barel. 1983. The ecological differentiation of two closely resembling insectivorous haplochromine species (Cichlidae) from Lake Victoria (H. iris and H. hiatus; Pisces, Cichlidae). Neth. J. Zool. 33: 232–273.Google Scholar
  40. Hughes, N.F. 1983. A study of the Nile perch, an introduced predator in the Kavirondo Gulf of Lake Victoria. Oxford Univ. Nile Perch Project, Oxford. 75 pp.Google Scholar
  41. Hughes, N.F. 1986. Changes in the feeding biology of the Nile perch, Lates niloticus (L.) (Pisces: Centropomidae), in Lake Victoria, East Africa since its introduction in 1960, and its impact on native fish community of the Nyanza Gulf. J. Fish Biol. 29: 541–548.Google Scholar
  42. Kaufman, L. 1986. Why the ark is sinking. pp. 1–41. In: L. Kaufman & K. Mallory (ed.) The Last Extinctions, The MIT Press, Cambridge.Google Scholar
  43. Kempinger, J.J. & R.F. Carline. 1977. Dynamics of the walleye (Stizostedion vitreum vitreum) population in Escanaba Lake, Wisconsin, 1955–72. J. Fish. Res. Board Can. 34: 1800–1811.Google Scholar
  44. Kornfield, I. & K.E. Carpenter. 1984. Cyprinids of Lake Lanao, Philippines: taxonomic validity, evolutionary rates and speciation scenarios. pp. 69–84. In: A.A. Echelle & I. Kornfield (ed.) Evolution of Fish Species Flocks, University of Maine at Orono Press, Orono.Google Scholar
  45. Kornfield, I. & A.A. Echelle. 1984. Who's tending the flock? pp. 251–254. In: A.A. Echelle & I. Kornfield (ed.) Evolution of Fish Species Flocks, University of Maine at Orono Press, Orono.Google Scholar
  46. Kudhongania, A.W. & A.J. Cordone. 1974. Batho-spatial distribution patterns and biomass estimates of the major demersal fishes in Lake Victoria. Afr. J. Trop. Hydrobiol. Fish. 3: 15–31.Google Scholar
  47. Ligtvoet, W. & O.C. Mkumbo. 1990. Stock assessment of Nile perch in Lake Victoria. pp. 35–74. In: CIFA, Report of the 5th Session of the Sub-committee for the Development and Management of the Fisheries in Lake Victoria, Mwanza, Tanzania, 12–14 September 1989, FAO Fish. Rep. 430.Google Scholar
  48. Ligtvoet, W. & F. Witte. 1991. Perturbation through predator introduction: effects on the food web and fish yields in Lake Victoria (East Africa). pp. 263–268. In: O. Ravera (ed.) Perturbation and Recovery of Terrestial and Aquatic Ecosystems, Elliss Horwood Ltd., Chichester.Google Scholar
  49. Marten, G.G. 1979. Impact of fishing on the inshore fishery of Lake Victoria (East Africa). J. Fish. Res. Board Can. 36: 891–900.Google Scholar
  50. McCune, A.R., K.S. Thomson & P.E. Olsen. 1984. Semionotid fishes from the mesozoic Great Lakes of North America. pp. 27–44. In: A.A. Echelle & I. Kornfield (ed.) Evolution of Fish Species Flocks, University of Maine at Orono Press, Orono.Google Scholar
  51. Meyer, A. 1987. Phenotypic plasticity and heterochrony in Cichlasoma managuense (Pisces, Cichlidae) and their implications for speciation in cichlid fishes. Evolution 4: 1357–1369.Google Scholar
  52. Meyer, A., T.D. Kocher, P. Basasibwaki & A.C. Wilson. 1990. Monophyletic origin of Lake Victoria cichlid fishes suggested by mitochondrial DNA sequences. Nature 347: 550–553.Google Scholar
  53. Ochumba, P.B.O. 1987. Periodic massive fish kills in the Kenyan part of Lake Victoria. Water Quality Bulletin 12: 119–122, 130.Google Scholar
  54. Ochumba, P.B.O. & D.I. Kibaara. 1989. Observations on bluegreen algal blooms in the open waters of Lake Victoria, Kenya. African Journal of Ecology 27: 23–34.Google Scholar
  55. Ogari, J. 1985. Distribution, food and feeding habits of Lates niloticus in the Nyanza Gulf of Lake Victoria (Kenya). pp. 68–80. In: CIFA, Report of the 3rd Session of the Subcommittee for the Development and Management of the Fisheries in Lake Victoria, Jinja, Uganda, 4–5 October 1984, FAO Fish. Rep. 335.Google Scholar
  56. Ogari, J. & A. Asila. 1990. The state of Lake Victoria fisheries, Kenya waters. pp. 18–23. In: CIFA, Report of the 5th Session of the Sub-committee for the Development and Management of the Fisheries in Lake Victoria, Mwanza, Tanzania, 12–14 September 1989, FAO Fish. Rep. 430.Google Scholar
  57. Ogari, J. & 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. J. Fish Biol. 32: 571–577.Google Scholar
  58. Ogutu-Ohwayo, R. 1985. The effects of predation by Nile perch introduced into Lake Kyoga (Uganda) in relation to the fisheries of Lake Kyoga and Lake Victoria. pp. 18–39. In: CIFA, Report of the 3rd Session of the Sub-committee for the Development and Management of the Fisheries in Lake Victoria, Jinja, Uganda, 4–5 October 1984, FAO Fish. Rep. 335.Google Scholar
  59. Ogutu-Ohwayo, R. 1990a. The decline of the native fishes of Lakes Victoria and Kyoga (East Africa) and the impact of introduced species, especially the Nile perch, Lates niloticus and the Nile tilapia, Oreochromis niloticus. Env. Biol. Fish. 27: 81–96.Google Scholar
  60. Ogutu-Ohwayo, R. 1990b. The reduction in fish species diversity in Lakes Victoria and Kyoga (East Africa) following human exploitation and introduction of non-native fishes. J. Fish Biol. 37 (Suppl. A): 207–208.Google Scholar
  61. Ogutu-Ohwayo, R. 1990c. Changes in the prey ingested and the variations in the Nile perch and other fish stocks of Lake Kyoga and the northern waters of Lake Victoria (Uganda). J. Fish Biol. 37: 55–63.Google Scholar
  62. Oijen van, M.J.P. 1982. Ecological differentiation among the haplochromine piscivorous species of Lake Victoria. Neth. J. Zool. 32: 336–363.Google Scholar
  63. Oijen van, M.J.P. 1991. A revision of the piscivorous haplochromine cichlids of Lake Victoria, Part I. Zool. Verb. Leiden 272 (in press).Google Scholar
  64. Oijen van, M.J.P., F. Witte & E.L.M. Witte-Maas. 1981. An introduction to ecological and taxonomic investigations on the haplochromine cichlids from the Mwanza Gulf of Lake Victoria. Neth. J. Zool. 31: 149–174.Google Scholar
  65. Okaronon, J., T. Acere & D. Ocenodongo. 1985. The current state of the fisheries in the northern portion of Lake Victoria. pp. 89–98. In: CIFA, Report of the 3rd Session of the Subcommittee for the Development and Management of the Fisheries in Lake Victoria, Jinja, Uganda, 4–5 October 1984. FAO Fish. Rep. 335.Google Scholar
  66. Okedi, J. 1971. Further observations on the ecology of the Nile perch (Lates niloticus Linne) in Lake Victoria and Lake Kyoga. Ann. Rep. E. Affr. Freshwat. Fish. Res. Org. 1970: 42–55.Google Scholar
  67. Okemwa. E.M. 1981. Changes in fish species composition of Nyanza Gulf of Lake Victoria. pp. 138–156. In: Proceedings of the Workshop of the Kenya Marine and Fisheries Research Institute on Aquatic Resources of Kenya. July 13–19, 1981, Kenya National Academy for the Advancement of Arts and Science, Nairobi.Google Scholar
  68. Okemwa, E.N. 1984. Potential fishery of Nile perch (Lates niloticus) Linne (Pisces: Centropomidae) in Nyanza Gulf of Lake Victoria, East Africa. Hydrobiologia 108: 121–126.Google Scholar
  69. Prins, R.A. & R. Hengeveld. 1989. Soortenverlies en genenbehoud (Species loss and gene preservation). pp. 9–21. In: R.A. Prins & H.M. van Emden (ed.) Het Verdwijnen van Soorten, Biologische Raad, KNAW, Amsterdam.Google Scholar
  70. Rapport, D.J., H.A. Regier & T.C. Hutchinson. 1985. Ecosystem behaviour under stress. Amer. Nat. 125: 617–640.Google Scholar
  71. Ribbink, A.J. 1987. African lakes and their fishes: conservation scenarios and suggestions. Env. Biol. Fish. 19: 3–26.Google Scholar
  72. Seegers. L. 1987. Ein neuer Haplochromisverwandter aus Ost Afrika sowie einige Bemerkungen zur Fischfauna des Victoriasees. Die Aquarien- und Terrarienzeitschrift, DATZ 401: 263–267.Google Scholar
  73. Sibly, R.M. & P. Calow. 1986. Physiological ecology of animals. Blackwell Scientific Publications, Oxford. 179 pp.Google Scholar
  74. Smith, G.R. & T.N. Todd. 1984. Evolution of species flocks of fishes in north temperate lakes. pp. 45–68. In: A.A. Echelle & I. Kornfield (ed.) Evolution of Fish Species Flocks, University of Maine at Orono Press, Orono.Google Scholar
  75. Stager, J.C., P.N. Reinthal & D.A. Livingstone. 1986. A 25,000-year history for Lake Victoria. East Africa, and some comments on its significance for the evolution of cichlid fishes. Freshw. Biol. 16: 15–19.Google Scholar
  76. Taylor, J.N., W.R. Courtenay, Jr. & J.A. McCann. 1984. Known impacts of exotic fishes in the continental United States. pp. 322–373. In: W.R. Courtenay, Jr. & J.R. Stauffer, Jr. (ed.) Distribution, Biology and Management of Exotic Fishes, Johns Hopkins University Press, Baltimore.Google Scholar
  77. Turner, J.L. 1977a. Some effects of demersal trawling in Lake Malawi (Lake Nvasa) from 1968 to 1974. J. Fish Biol. 10: 261–271.Google Scholar
  78. Turner, J.L. 1977b. Changes in the size structure of cichlid populations of Lake Malawi resulting from bottom trawling. J. Fish. Res. Board Can. 34: 232–238.Google Scholar
  79. Van Couvering, J.A.H. 1982. Fossil cichlid fish of Africa. Spec. Pap. Paleont. 19: 1–103.Google Scholar
  80. Vermeij, G.J. 1986. The biology of human caused extinction. pp. 28–49. In: B.G. Norton (ed.) The Preservation of Species, Princeton University Press, Princeton.Google Scholar
  81. Vos, L. de, J. Snoeks & D. Thys van den Audenaerde. 1990. The effects of Tilapia introductions in Lake Luhondo, Rwanda. Env. Biol. Fish. 27: 303–308.Google Scholar
  82. Wanink, J.H. 1991. Survival in a perturbed environment: the effects of Nile perch introduction on the zooplanktivorous fish community of Lake Victoria. pp. 269–275. In: O. Ravera (ed.) Terrestial and Aquatic Ecosystems, Perturbation and Recovery, Ellis Horwood, New York.Google Scholar
  83. Welcomme, R.L. 1981. Register of international transfers of inland fish species. FAO Fish. Tech. Pap. 213. 120 pp.Google Scholar
  84. Welcomme, R.L. 1984. International transfers of inland fish species. pp. 22–40. In: W.R. Courtenay, Jr. & J.R. Stauffer, Jr. (ed.) Distribution, Biology and Management of Exotic Fishes, Johns Hopkins University Press, Baltimore.Google Scholar
  85. Welcomme, R.L. 1988. International introductions of inland aquatic species. FAO Fish. Tech. Pap. 294. 319 pp.Google Scholar
  86. Wilson, E.O. 1988. The current state of biological diversity. pp. 3–18. In: E.O. Wilson (ed.) Biodiversity, National Academy Press, Washington, D.C.Google Scholar
  87. Witte, F. 1981. Initial results of the ecological survey of the haplochromine fishes from the Mwanza Gulf of Lake Victoria, Tanzania: breeding patterns, trophic and species distribution. Neth. J. Zool. 31: 175–202.Google Scholar
  88. Witte, F. 1984a. Consistency and functional significance of morphological differences between wild-caught and domestic Haplochromis squamipinnis (Pisces, Cichlidae). Neth. J. Zool. 34: 596–612.Google Scholar
  89. Witte, F. 1984b. Ecological differentiation in Lake Victoria haplochromines: comparison of cichlid species flocks in African lakes. pp. 155–167. In: A.A. Echelle & I. Kornfield (ed.) Evolution of Fish Species Flocks, University of Maine at Orono Press, Orono.Google Scholar
  90. Witte, F., C.D.N. Barel & R.J.C. Hoogerhoud. 1990. Phenotypic plasticity of anatomical structures and its ecomorphological significance. Neth. J. Zool. 40: 278–298.Google Scholar
  91. Witte, F. & P.C. Goudswaard. 1985. Aspects of haplochromine fishery in southern Lake Victoria. pp. 81–88. In: CIFA, Report of the 3rd Session of the Sub-committee for the Development and Management of the Fisheries in Lake Victoria, Jinja, Uganda, 4–5 October 1984, FAO Fish. Rep. 335.Google Scholar
  92. Witte, F. & M.J.P. van Oijen. 1990. Taxonomy, ecology and fishery of haplochromine trophic groups. Zool. Verh. Leiden 262: 1–47.Google Scholar
  93. Witte, F. & E.L.M. Witte-Maas. 1987. Implications for taxonomy and functional morphology of intra-specific variation in haplochromine cichlids of Lake Victoria. pp. 35–118. In: F. Witte, From Form to Fishery, Ph.D. Thesis, Rijksuniversiteit Leiden, Leiden.Google Scholar
  94. Zaret, T.M. 1979. Predation in freshwater fish communities. pp. 135–143. In: H. Clepper (ed.) Predator-Prey Systems in Fisheries Management, Sport Fishing Institute, Washington, D.C.Google Scholar
  95. Zaret, T.M. 1982. The stability/diversity controversy: a test of hypotheses. Ecology 63: 721–731.Google Scholar
  96. Zaret, T.M. & R.T. Paine. 1973. Species introduction in a tropical lake. Science 182: 449–455.Google Scholar

Copyright information

© Kluwer Academic Publishers 1992

Authors and Affiliations

  • Frans Witte
    • 1
  • Tijs Goldschmidt
    • 1
  • Jan Wanink
    • 1
  • Martien van Oijen
    • 2
  • Kees Goudswaard
    • 1
  • Els Witte-Maas
    • 1
  • Niels Bouton
    • 1
  1. 1.Research Group on Ecological Morphology, Zoologisch LaboratoriumRijksuniversiteit LeidenLeidenThe Netherlands
  2. 2.Nationaal Natuurhistorisch MuseumLeidenThe Netherlands

Personalised recommendations