Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery

 

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dc.contributor.advisor Jarre, Astrid en_ZA
dc.contributor.advisor Van der Lingen, Carl D en_ZA
dc.contributor.author Astor, Nicole en_ZA
dc.date.accessioned 2014-11-05T03:56:01Z
dc.date.available 2014-11-05T03:56:01Z
dc.date.issued 2014 en_ZA
dc.identifier.citation Astor, N. 2014. Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery. University of Cape Town. en_ZA
dc.identifier.uri http://hdl.handle.net/11427/9189
dc.description Includes bibliographical references. en_ZA
dc.description.abstract A knowledge-based tool was developed to assess the efficacy of the ecosystem approach to fisheries in the South African anchovy fishery. South Africa has agreed to implement an ecosystem approach to fisheries (EAF) management. The EAF management comprises of three dimensions; ecological well-being, human well-being and ability to achieve. The focus for this study was on the ecological well-being dimension. Meetings were held with experts to revise objectives stemming from issues in the anchovy fishery documented earlier and indicators linking to these objectives. A hierarchical tree was constructed using these indicators and objectives. The objectives were divided into pressure and state. The indicators were transformed using piecewise linear transformation on to a common scale from -1 to 1. Thresholds were also decided to assess when the EAF implementation was considered to be 'good' (1), 'ok' (0) and 'bad' (-1). Weighted means were applied through the hierarchy. The overall resulting output, the truth value, was then used to assess how well the ecological dimension of the anchovy fishery had been doing over time. This showed the implementation efficacy of an EAF within the ecological dimension had been doing badly in 1987-1996, and since 1997 the ecological dimension of the EAF has been doing better. Sensitivity tests on the weights also showed that the knowledge based tool was robust to changes in weights. This allowed for experts to have slight differences in opinion over the way the weights should be distributed, but without these differences in opinion affecting the overall truth value. Sensitivity tests on the thresholds of one of the indicators showed that the outcome of the indicator is sensitive to changes in the thresholds. However, when looking at the overall truth values or the objectives, the changes to the thresholds did not affect the resulting objective values or the overall truth value that much. Although the indicator values change with changes in the thresholds, looking at the whole knowledge based tool it is fairly robust to moderate changes in thresholds. en_ZA
dc.language.iso eng en_ZA
dc.title Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery 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 Astor, N. (2014). <i>Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery</i>. (Thesis). University of Cape Town ,Faculty of Science ,Department of Biological Sciences. Retrieved from http://hdl.handle.net/11427/9189 en_ZA
dc.identifier.chicagocitation Astor, Nicole. <i>"Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery."</i> Thesis., University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 2014. http://hdl.handle.net/11427/9189 en_ZA
dc.identifier.vancouvercitation Astor N. Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery. [Thesis]. University of Cape Town ,Faculty of Science ,Department of Biological Sciences, 2014 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/9189 en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Astor, Nicole AB - A knowledge-based tool was developed to assess the efficacy of the ecosystem approach to fisheries in the South African anchovy fishery. South Africa has agreed to implement an ecosystem approach to fisheries (EAF) management. The EAF management comprises of three dimensions; ecological well-being, human well-being and ability to achieve. The focus for this study was on the ecological well-being dimension. Meetings were held with experts to revise objectives stemming from issues in the anchovy fishery documented earlier and indicators linking to these objectives. A hierarchical tree was constructed using these indicators and objectives. The objectives were divided into pressure and state. The indicators were transformed using piecewise linear transformation on to a common scale from -1 to 1. Thresholds were also decided to assess when the EAF implementation was considered to be 'good' (1), 'ok' (0) and 'bad' (-1). Weighted means were applied through the hierarchy. The overall resulting output, the truth value, was then used to assess how well the ecological dimension of the anchovy fishery had been doing over time. This showed the implementation efficacy of an EAF within the ecological dimension had been doing badly in 1987-1996, and since 1997 the ecological dimension of the EAF has been doing better. Sensitivity tests on the weights also showed that the knowledge based tool was robust to changes in weights. This allowed for experts to have slight differences in opinion over the way the weights should be distributed, but without these differences in opinion affecting the overall truth value. Sensitivity tests on the thresholds of one of the indicators showed that the outcome of the indicator is sensitive to changes in the thresholds. However, when looking at the overall truth values or the objectives, the changes to the thresholds did not affect the resulting objective values or the overall truth value that much. Although the indicator values change with changes in the thresholds, looking at the whole knowledge based tool it is fairly robust to moderate changes in thresholds. DA - 2014 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 2014 T1 - Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery TI - Evaluating the implementation efficacy of an ecosystem approach to fisheries in the South African anchovy fishery UR - http://hdl.handle.net/11427/9189 ER - en_ZA


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