Skip to main content

Prey selection by molluscivorous cichlids foraging on a schistosomiasis vector snail, Biomphalaria glabrata


This paper considers prey size selection by four molluscivorous cichlids feeding on the intermediate host snail of Schistosoma parasites, Biomphalaria glabrata. Haplochromis ishmaeli obtains its prey by crushing the snails between the pharyngeal jaws, whereas H. xenognathus, H. sauvagei and Macropleurodus bicolor apply both pharyngeal crushing and oral shelling. The fishes crushed significantly more snails with the highest reward in biomass per second of crushing. Oral shelling occurred far less often than pharyngeal crushing. Encounter rates with prey showed significant variations between different size classes of prey. The fish have no overall knowledge of snail availability in a tank. The probability that a snail will be eaten at encounter, calculated from the number encountered and the number eaten, reflects the prey size preference of the fish. Those snails with the highest biomass/crushing-time ratio had the highest probability of being crushed; observed and predicted prey size preferences corresponded well. Although for oral shelling the potential reward in biomass per second is of the same magnitude as for crushing, the probability of successful shelling is very low. Apparently the fish prefer prey with lowest risks.

This is a preview of subscription content, access via your institution.


  • Anderson Ch, Gobert E (1924) Des mesures prophylactiques applicable contre la biharziose en Tunisie. Arch Inst Pasteur Tunis 13:215–218

    Google Scholar 

  • Coates D, Redding-Coates TA (1981) Ecological problems associated with irrgiation canals in the Sudan with particular reference to the spread of bilharziasis, malaria and aquatic weeds and the ameliorative role of fishes. Intern J Environmental Studies 16:207–212

    Google Scholar 

  • Fryer G, Iles TD (1972) The cichlid fishes of the great lakes of Africa. Their biology and evolution. Oliver & Boyd, Edinburgh

    Google Scholar 

  • Greenwood PH (1964) 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 

  • Greenwood PH (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 

  • Greenwood PH (1980) Towards a phyletic classification of the ‘genus’ Haplochromis (Pisces, Cichlidae) and related taxa. Part II: the species from Lake Victoria, Nabugabo, Edward, George and Kivu. Bull Br Mus nat Hist (Zool) 39:1–101

    Google Scholar 

  • Hairston NG, Wurzinger KH, Burch JB (1975) Non-chemical methods of snail control. WHO/SCHISTO/75.40 Geneva, Switserland

  • Hart PJB (1986) Foraging in teleost fishes. In: Pitcher TJ (ed) The Behaviour of teleost fishes. Croom Helm, London Sydney, pp 211–236

    Google Scholar 

  • Hoogerhoud RJC (1984) A taxonomic reconsideration of the haplochromine genera Gaurochromis Greenwood, 1981 and Labrochromis Regan, 1920 (Pisces, Cichlidae). Neth J Zool 34:539–566

    Google Scholar 

  • Hoogerhoud RJC (1986a) Taxonomic and ecological aspects of morphological plasticity in molluscivorous haplochromines (Pisces, Cichlidae). Ann Kon Mus Mid Afr, Zool Wetensch 251:131–134

    Google Scholar 

  • Hoogerhoud RJC (1986b) Ecological morphology of some cichlid fishes. Thesis, Leiden

  • Katunzi EF (1983) Seasonal variations in the food of a molluscivorous cichlid Haplochromis sauvagei Pfeffer 1896. Neth J Zool 33:337–341

    Google Scholar 

  • Krebs JR, Stephens DW, Sutherland WJ (1983) Perspectives in optimal foraging. In: Perspectives in Ornithology. Essays presented for the Centennial of the American Ornithologists' Union. Cambridge University Press

  • McCullough FS (1981) Biological control of the snail intermediate hosts of human Schistosoma spp: a review of its present status and future prospects. Acta Tropica 38:5–13

    Google Scholar 

  • Mittelbach GG (1981) Foraging efficiency and body size: a study of optimal diet and habitat use by bluegills. Ecology 62:1370–1386

    Google Scholar 

  • Slootweg R (1985) Biological control of snail intermediate hosts of Schistosoma spp. by fish: a summary of the literature. Reports of the Research-Group Ecological Morphology of Fishes 34. State University Leiden, Netherlands

    Google Scholar 

  • Stein RA, Gosse-Goodman C, Marschall EA (1984) Using time and energetic measures of cost in estimating prey value for fish predators. Ecology 65:702–715

    Google Scholar 

  • Townsend CR, Winfield IJ (1985) The application of optimal foraging theory to feeding behaviour in fish. In: Tytler P, Calow P (eds) Fish energetics New perspectives. Croom Helm, London Sydney, pp 67–98

    Google Scholar 

  • Witte F (1981) Intial results of the ecological survey of the Haplochromine cichlid fishes from the Mwanza Gulf of Lake Victoria (Tanzania): breeding patterns, trophic and species distribution. With recommendations for commercial trawl fishery. Neth J Zool 31:175–202

    Google Scholar 

  • Witte F (1984a) Ecological differentiation in Lake Victoria Haplochromines: comparison of cichlid species flocks in African lakes. In: Echelle AA, Kornfield I (eds) Evolution of fish species flocks. University of Maine at Orono Press

  • Witte F (1984b) Consistency and functional significance of morphological differences between wild-caught and domestic Haplochromis squamipinnis (Pisces, Cichlidae). Neth J Zool 34:596–613

    Google Scholar 

Download references

Author information

Authors and Affiliations


Rights and permissions

Reprints and Permissions

About this article

Cite this article

Slootweg, R. Prey selection by molluscivorous cichlids foraging on a schistosomiasis vector snail, Biomphalaria glabrata . Oecologia 74, 193–202 (1987).

Download citation

  • Received:

  • Issue Date:

  • DOI:

Key words

  • Molluscivorous cichlids
  • Prey selection
  • Biomphalaria glabrata