Fish parasites as bio-indicators of heavy metals in two South African embayments

 

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dc.contributor.advisor Reed, Cecile en_ZA
dc.contributor.advisor Lamberth, Stephen Justin en_ZA
dc.contributor.advisor Avenant-Oldewage, Annemarie en_ZA
dc.contributor.author Morris, Thomas Colin en_ZA
dc.date.accessioned 2015-12-04T19:32:11Z
dc.date.available 2015-12-04T19:32:11Z
dc.date.issued 2015 en_ZA
dc.identifier.citation Morris, T. 2015. Fish parasites as bio-indicators of heavy metals in two South African embayments. University of Cape Town. en_ZA
dc.identifier.uri http://hdl.handle.net/11427/15608
dc.description.abstract The Cape Elephant fish (Callorhinchus capensis) and two common sand shark species (Rhinobatos annulatus and Rhinobatos blochii) were caught off False Bay and Saldanha Bay and surveyed for their parasite community in 2013 and 2014. The surveys were used to build species accumulation curves (SAC) and calculate biodiversity indices, particularly, rarefied species richness, Shannon Weiner's diversity index, Simpson's index and Pielou's J index. The biodiversity indices were correlated with the host's biological data and parasite infection data, to determine the parasite community structure and provide insight into the host's community structure. The parasites identified in C. capensis (n=19) include a cestode (Gyrocotyle plana), two monogeneans (Callorhynchicotyle callorhynchi and Callorhinchicola multitesticulatus) and an isopod (Anilocra sp.). The cestode was the most prevalent at 68.4 % and the monogenean, C. callorhynchi was the most abundant (1.68 ±0.78) and had the highest infection intensity (4.00 ±1.45). The SAC and biodiversity measures indicate a uniform parasite community across the host population, suggesting a highly interactive shark community. Conversely, Rhinobatos annulatus (n=19) and R. blochii (n=17) had very limited parasite infection with two species of nematode found infecting the stomach (Proleptus obtusus) and encysted in the kidneys (Ascaris sp.) and a copepod species (Clavelottis sp.) found infecting the gills. Proleptus obtusus was the most prevalent (31.6 % and 29.4%), the most abundant (1 ±0.37 and 3.68 ±2.76) and had the highest mean infection intensity (3.17 ±0.4 and 14 ±1.5). A cestode (Trilocularia sp.) was found infecting three specimens of R. annulatus from False Bay. The SAC and biodiversity indices combined with the limited parasite infection indicate a non-uniform parasite community across the host population, suggesting an isolationist population. Within the parasite community discovered, a potential biological indicator for heavy metal accumulation was identified to determine the levels of heavy metal pollution within these two anthropogenically impacted bays. Gyrocotyle plana and Proleptus obtusus were chosen as potential indicators due to their high prevalence and the close relationship they have with their hosts. The results support the use of higher trophic level animals as biological indicators. The results also indicate that G. plana is an incredibly good accumulator of certain metals, particularly As (4073.52 ± 5561.54 μg/g), Mn (522.16 ± 578.21 μg/g), Pb (64.87 ± 101.7 μg/g), Ti (1821.42 ± 1348.16 μg/g), and Zn (12439.57 ± 9743.60 μg/g). Unfortunately water and sediment samples were not tested, however, concentrations were compared to baseline values, and the accumulation of these metals are orders of magnitude above the surrounding environment. Proleptus obtusus did not significantly accumulate metals from its surrounding environment. These results show that parasites can be used to infer their own and their host's community structure and confirm their usefulness as indicators of pollution in marine ecosystems. en_ZA
dc.language.iso eng en_ZA
dc.subject.other Biological Sciences en_ZA
dc.subject.other Marine Research en_ZA
dc.title Fish parasites as bio-indicators of heavy metals in two South African embayments en_ZA
dc.type Master Thesis
uct.type.publication Research en_ZA
uct.type.resource Thesis en_ZA
dc.publisher.institution University of Cape Town
dc.publisher.faculty Faculty of Science en_ZA
dc.publisher.department Department of Biological Sciences en_ZA
dc.type.qualificationlevel Masters
dc.type.qualificationname MSc en_ZA
uct.type.filetype Text
uct.type.filetype Image
dc.identifier.apacitation Morris, T. C. (2015). <i>Fish parasites as bio-indicators of heavy metals in two South African embayments</i>. (Thesis). University of Cape Town ,Faculty of Science ,Department of Biological Sciences. Retrieved from http://hdl.handle.net/11427/15608 en_ZA
dc.identifier.chicagocitation Morris, Thomas Colin. <i>"Fish parasites as bio-indicators of heavy metals in two South African embayments."</i> Thesis., University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 2015. http://hdl.handle.net/11427/15608 en_ZA
dc.identifier.vancouvercitation Morris TC. Fish parasites as bio-indicators of heavy metals in two South African embayments. [Thesis]. University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 2015 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/15608 en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Morris, Thomas Colin AB - The Cape Elephant fish (Callorhinchus capensis) and two common sand shark species (Rhinobatos annulatus and Rhinobatos blochii) were caught off False Bay and Saldanha Bay and surveyed for their parasite community in 2013 and 2014. The surveys were used to build species accumulation curves (SAC) and calculate biodiversity indices, particularly, rarefied species richness, Shannon Weiner's diversity index, Simpson's index and Pielou's J index. The biodiversity indices were correlated with the host's biological data and parasite infection data, to determine the parasite community structure and provide insight into the host's community structure. The parasites identified in C. capensis (n=19) include a cestode (Gyrocotyle plana), two monogeneans (Callorhynchicotyle callorhynchi and Callorhinchicola multitesticulatus) and an isopod (Anilocra sp.). The cestode was the most prevalent at 68.4 % and the monogenean, C. callorhynchi was the most abundant (1.68 ±0.78) and had the highest infection intensity (4.00 ±1.45). The SAC and biodiversity measures indicate a uniform parasite community across the host population, suggesting a highly interactive shark community. Conversely, Rhinobatos annulatus (n=19) and R. blochii (n=17) had very limited parasite infection with two species of nematode found infecting the stomach (Proleptus obtusus) and encysted in the kidneys (Ascaris sp.) and a copepod species (Clavelottis sp.) found infecting the gills. Proleptus obtusus was the most prevalent (31.6 % and 29.4%), the most abundant (1 ±0.37 and 3.68 ±2.76) and had the highest mean infection intensity (3.17 ±0.4 and 14 ±1.5). A cestode (Trilocularia sp.) was found infecting three specimens of R. annulatus from False Bay. The SAC and biodiversity indices combined with the limited parasite infection indicate a non-uniform parasite community across the host population, suggesting an isolationist population. Within the parasite community discovered, a potential biological indicator for heavy metal accumulation was identified to determine the levels of heavy metal pollution within these two anthropogenically impacted bays. Gyrocotyle plana and Proleptus obtusus were chosen as potential indicators due to their high prevalence and the close relationship they have with their hosts. The results support the use of higher trophic level animals as biological indicators. The results also indicate that G. plana is an incredibly good accumulator of certain metals, particularly As (4073.52 ± 5561.54 μg/g), Mn (522.16 ± 578.21 μg/g), Pb (64.87 ± 101.7 μg/g), Ti (1821.42 ± 1348.16 μg/g), and Zn (12439.57 ± 9743.60 μg/g). Unfortunately water and sediment samples were not tested, however, concentrations were compared to baseline values, and the accumulation of these metals are orders of magnitude above the surrounding environment. Proleptus obtusus did not significantly accumulate metals from its surrounding environment. These results show that parasites can be used to infer their own and their host's community structure and confirm their usefulness as indicators of pollution in marine ecosystems. DA - 2015 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2015 T1 - Fish parasites as bio-indicators of heavy metals in two South African embayments TI - Fish parasites as bio-indicators of heavy metals in two South African embayments UR - http://hdl.handle.net/11427/15608 ER - en_ZA


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