The feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystem

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dc.contributor.advisorField, John Gen_ZA
dc.contributor.authorJames, Andrew Gordonen_ZA
dc.date.accessioned2014-10-11T12:21:33Z
dc.date.available2014-10-11T12:21:33Z
dc.date.issued1988en_ZA
dc.descriptionBibliography: leaves 179-231.en_ZA
dc.description.abstractThe two main schools of thought regarding the diets of intermediate microphagous clupeids are: A) that they are herbivorous and B) that they are omnivorous, but consume mainly zooplankton. The former view has been employed to explain their abundance in upwelling areas, since their purported ability to efficiently utilise the primary producers shortens the pelagic food chain to 1 or 2 links. The literature concerning the trophic ecology of some commercially important clupeids is reviewed and it is concluded that few are true phytophagists. Most are omnivorous and derive the bulk of their energy from zooplankton. Results indicating that these fish are herbivorous are largely due to inadequate sampling strategies and analytical techniques. The results of field work show that Engraulis capensis feeds selectively upon meso- and macro-zooplankton. Laboratory experiments supported these findings. Prey are selected on the basis of size and particulate feeding is the dominant mode of intake when the' fish are presented with a mixed size assemblage of prey. Engraulis capensis cannot filter feed on particles less than 0.200mm maximum dimension, and there is a threshold size of approximately 0.700mm when feeding behaviour switches from filter to particulate feeding. Particulate feeding produced faster clearance rates than filtering, and the Cape anchovy feeds at maximum efficiency over most of their prey size spectrum.en_ZA
dc.identifier.apacitationJames, A. G. (1988). <i>The feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystem</i>. (Thesis). University of Cape Town ,Faculty of Science ,Department of Biological Sciences. Retrieved from http://hdl.handle.net/11427/8409en_ZA
dc.identifier.chicagocitationJames, Andrew Gordon. <i>"The feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystem."</i> Thesis., University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 1988. http://hdl.handle.net/11427/8409en_ZA
dc.identifier.citationJames, A. 1988. The feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystem. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - James, Andrew Gordon AB - The two main schools of thought regarding the diets of intermediate microphagous clupeids are: A) that they are herbivorous and B) that they are omnivorous, but consume mainly zooplankton. The former view has been employed to explain their abundance in upwelling areas, since their purported ability to efficiently utilise the primary producers shortens the pelagic food chain to 1 or 2 links. The literature concerning the trophic ecology of some commercially important clupeids is reviewed and it is concluded that few are true phytophagists. Most are omnivorous and derive the bulk of their energy from zooplankton. Results indicating that these fish are herbivorous are largely due to inadequate sampling strategies and analytical techniques. The results of field work show that Engraulis capensis feeds selectively upon meso- and macro-zooplankton. Laboratory experiments supported these findings. Prey are selected on the basis of size and particulate feeding is the dominant mode of intake when the' fish are presented with a mixed size assemblage of prey. Engraulis capensis cannot filter feed on particles less than 0.200mm maximum dimension, and there is a threshold size of approximately 0.700mm when feeding behaviour switches from filter to particulate feeding. Particulate feeding produced faster clearance rates than filtering, and the Cape anchovy feeds at maximum efficiency over most of their prey size spectrum. DA - 1988 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 1988 T1 - The feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystem TI - The feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystem UR - http://hdl.handle.net/11427/8409 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/8409
dc.identifier.vancouvercitationJames AG. The feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystem. [Thesis]. University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 1988 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/8409en_ZA
dc.language.isoeng
dc.publisher.departmentDepartment of Biological Sciencesen_ZA
dc.publisher.facultyFaculty of Scienceen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherZoologyen_ZA
dc.titleThe feeding ecology of and carbon and nitrogen budgets for Engraulis capensis in the southern Benguela ecosystemen_ZA
dc.typeDoctoral Thesis
dc.type.qualificationlevelDoctoral
dc.type.qualificationnamePhDen_ZA
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
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