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The role of microhabitats within mangroves: an invertebrate and fish larval perspective

  • Authors: Vorsatz, Lyle Dennis
  • Date: 2020
  • Subjects: Mangrove ecology -- South Africa , Mangrove forests -- South Africa , Niche (Ecology) , Rhizophora mucronata , Acanthaceae , Rhizophoraceae , Fishes -- Larvae -- South Africa , Aquatic ecology -- South Africa
  • Language: English
  • Type: text , Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10962/167644 , vital:41499
  • Description: Microhabitats provided through structural complexity are central for the diversity, productivity, connectivity and niche differentiation within and among ecosystems. Mangrove forests afford juvenile fish and invertebrates with nursery and recruitment habitats, facilitated by the fine scale configuration of their specialised root systems. Although the importance of mangroves for resident and transient juveniles is well recognised, the roles that mangrove microhabitats play for larvae is not yet comprehensively understood. This study aimed to determine how microhabitats with varying degrees of complexity influence the composition, abundance and distribution of larval communities that inhabit mangrove forests and the physiological responses of larvae to acute temperature variations in relation to ontogenetic stage and microenvironment exposure. Two relatively pristine study sites were selected to represent a warm temperate and subtropical mangrove system in the Eastern Cape and KwaZulu-Natal on the east coast of South Africa, respectively. The differences in complexity among the root systems of Rhizophora mucronata, Avicennia marina and Bruguiera gymnorhiza were assessed using 3D scanning and the computed 3D models were then analysed using four complexity metrics. Results indicated that A. marina is the most complex in terms of surface-volume ratio, R. mucronata has the most interstitial space among its roots and B. gymnorhiza and R. mucronata differ in their fractal dimensions. Larvae collected in each microhabitat at each site using light traps showed that, despite temperature and salinity homogeneity across microenvironments, spatio-temporal differences occurred in both fish and invertebrate assemblages. This trend suggests that microhabitat structural complexity exerts an influence on larval community composition by acting as a microscape of available habitat, which ensures ecological linkages within and among the mangrove forest and adjacent ecosystems. In addition, the oxygen consumption rates of mangrove-associated brachyuran larvae varied according to mangrove microhabitat, whereby larvae collected at less complex environments had the highest metabolic rates at increased temperatures. Moreover, ontogenetic shifts in physiology were prevalent as older brachyuran larvae were more eurythermal than earlier stages, suggesting that thermally stressful events will have a greater impact on recently spawned larvae. Overall, the interstitial spaces within individual root systems are the most important complexity measure, as utilisation of these mangrove microhabitats is scale-dependent, and larvae will most likely occupy spaces inaccessible to large predators. Likewise, microscale variation in the environmental conditions and ontogenetic stage of brachyuran larvae within the mangrove microscape, can amplify the physiological responses to rapid temperature variations. Results suggest that early stage larvae are the most vulnerable to mass-mortality, and if thermally stressful events increase in frequency, duration and magnitude, the larval supply for the successful recruitment into adult populations could be under threat. Through linking how mangrove microhabitat complexity influences larvae in terms of community metrics and physiology, this study paves the way for further advancement of our understanding of how microscale processes emerge into meso- and macroscale patterns and influence the stability and functioning of highly productive ecosystems.
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  • Date Issued: 2020

The role of northwest striking structures in controlling highgrade ore shoots at the Syama Gold Mine, Mali, West Africa

  • Authors: Soro, Ali
  • Date: 2020
  • Subjects: Syama Gold Mine , Gold ores -- Geology -- Mali , Veins (Geology) -- Mali
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10962/145209 , vital:38418
  • Description: This study intended to investigate the relationship between the NW striking structures and the high-grade ore shoots at the Syama gold mine in Mali, West Africa. All structural data collected since 1987 from drill core have been integrated to allow the interpretation and modelling of these NW-SE structures. The structures collected were grouped into three main groups; foliations/shears/faults, veins and joints/contacts/fractures. Micromine software was used to plot the structures, printed out on A3 paper and interpreted manually using tracing paper. Analysis and interpretation of stereographic plots has shown that the majority of the high-grade zones are generally located at the intersection of the NNE structures and the NW structures. The observed cross-cutting relationship between the NNE and the NW structures suggests two different generation of faults. It is suggested that the NW structures were active during the D4 deformation event (Standing, 2007) and have played a role in reactivating earlier (D3) NNE structures, allowing greater fluid flow and enhancing the gold grade. These zones are mainly defined by brecciation and stockwork veining. The E-W structures are believed to be the latest and are attributed to the D5 event. Although gold mineralisation is grossly controlled by the NNE structures, the NW structures need to be considered as major gold enrichment upgrading factors at Syama. It is therefore strongly recommended that ongoing exploration at Syama specifically target the intersection of the NW and NNE structures as favourable zones for high-grade mineralisation.
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  • Date Issued: 2020

The role of primary schools in promoting democratic values of justice, equality and liberty in pupils: a study of Shamva district, Zimbabwe

  • Authors: Dzavo, Joseph
  • Date: 2020
  • Subjects: Democracy and education , Education -- Zimbabwe -- History , Education, Primary -- Curricula
  • Language: English
  • Type: Doctoral theses , text
  • Identifier: http://hdl.handle.net/10353/27297 , vital:66696
  • Description: This study examines the role of primary schools in promoting democratic values of justice, equality and liberty in pupils in Shamva District, Zimbabwe. The study was necessitated by the continual abuse of democratic values by school leavers in the district before, during and after elections. Such continued abuses make one wonder if schools really inculcate democratic values of justice, equality and liberty in their pupilsas enshrined in the curriculum. Using a qualitative approach, the study is located within the interpretivist research paradigm. A case study design was adopted and three primary schools in Shamva District were purposively and conveniently selected for this study. The sample comprised three 3 primary schools heads, three 3 deputy heads, nine 9 teachers, five 5 school leavers and fifteen 15 prefects aged between 10 and 15 years old. Data was generated through semi-structured face-to-face interviews, focus group interviews and document analysis. The findings of the study revealed that schools had challenges in inculcating democratic values of justice, equality and liberty in learners. The challenges included difficulties in interpreting the syllabi on inculcation of democratic values of justice, equality and liberty in learners; democratic values being viewed as sensitive content usually misconstrued to be favouring certain political agendas by community members; and the lack of a clear cut democratic values curriculum framework to guide teachers on teaching democratic values of justice, equality and liberty. Some of the recommendations were that teachers should be protected by legal instruments like policies to enable them to freely teach sensitive content. Teachers also need empowerment in syllabus interpretation on the inculcation of democratic values to be able to effectively promote the teaching of democratic values of justice, equality and liberty. , Thesis (PhD) -- Faculty of Education, 2020
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  • Date Issued: 2020

The role of small-scale squid fisheries in sustaining livelihoods and maintaining marine resources in the context of climate change

  • Authors: Mkaza, Oyamangaye
  • Date: 2020
  • Subjects: Squids -- Presevation , Climate Change -- South Africa
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/50382 , vital:42158
  • Description: Small-scale fisheries depend on the ocean as a source of social and economic benefit for the world’s population, especially in developing countries. Coastal communities face challenges in ensuring that fisheries are sustainable and resilient to the effects of climate change. The collapse of small-scale squid fisheries in South Africa in 2013-2014 raised concerns in South Africa’s fishing industry, leading to various studies that focused on the marine environment. Small-scale fisheries are important in terms of their contribution to various national economies, job creation for coastal communities and the sustainability of human existence. Society needs a detailed knowledge of the living components of natural and managed systems, as global climate changes affect the functions of ecosystems and consequently the well-being of humans. A qualitative research approach using unstructured interviews with participants was appropriate for this study. This approach gave an opportunity for participants to explain their views and provide an in-depth understanding of their social phenomena. The significance of this study is that it broadens knowledge and understanding of how small-scale fishers respond and become resilient to climate change, shocks and other risks that affect social and ecological systems negatively and assists in forecasting the likelihood of a future collapse of the fishing industry. The study’s results indicate that squid fishers’ local knowledge supports the view that there are changes in the squid stocks, with fishers detailing the changing weather patterns and climatic conditions. The squid fishers identified unsustainable fishing practices that damage the spawning areas as a problem area. There was a general concern amongst the limited number of interviewees that the future of their livelihood was in peril and changes had to be made. Local knowledge and the perceived desire to care for the environment are important for managing squid resources and fostering communities’ resilience to climate change.
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  • Date Issued: 2020

The role of the Development Funding to promote Local Economic Development in the Sarah Baartman District

  • Authors: Kosi, Mlungiseleli Edward
  • Date: 2020
  • Subjects: Economic development -- Environmental aspects -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MDS
  • Identifier: http://hdl.handle.net/10948/48698 , vital:41060
  • Description: This study concentrated on the role of development funding to promote Local Economic Development (LED) in the Sarah Baartman District (SBD). Although the research discussed the funding institutions available for Small-, Medium- and Micro- Enterprises (SMMEs) in general, the main focus of this study was the Local and Regional Economic Development (LRED) Grant Fund, which is solely established to support SMMEs in the Eastern Cape. A qualitative study was undertaken in the SBD that targeted two semi-rural municipalities in the Karoo. The Dr Beyers Naude and Koukamma Local Municipalities were targeted for this research. Both municipalities are semi-rural and located in the Karoo. The study found that in order to realise sustainable economic growth, LED must be encouraged and supported within the local space. The literature review encouraged the employment of participatory development as well as addressing issues of social structures as they reinforce limitations on growth and exposure. The District Development Model (DDM) highlights the coordination of Government programmes to a district. The model also significantly devolves Government functions and structures for integrated planning and implementation to district and metropolitan municipalities. Local government is viewed as the lowest sphere of Government, and is responsible for delivering basic services and the governance of local municipalities. This level of Government also places the performance, monitoring, evaluation, and reporting (PMER) of governance at a district level. Such PMER could enable a district to have first-hand performance reports regarding development in relevant jurisdictions. In attempting to address the problem of unemployment, poverty, and economic growth, the Department of Economic Development, Environmental Affairs and Tourism (DEDEAT) established the LRED Grant Fund, which is solely meant to assist SMMEs in the Eastern Cape. This fund is tailored to aid the initiatives and/or businesses in the following sectors: agro-processing, automotive, manufacturing, renewable energy, oceans economy, and tourism. However, there is a current concern regarding the LRED’s lack of transparency, communication, and uncertain turnaround time during application assessment and adjudication processes. The study also noted a lack of capacity, skills, and mentoring as a hinderance for projects to sustain
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  • Date Issued: 2020

The role of the expanded public works programme in reducing unemployment in Grahamstown

  • Authors: Adam, Zanele
  • Date: 2020
  • Subjects: Poverty Alleviation -- South Africa -- Grahamstown
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/49583 , vital:41738
  • Description: Unemployment is a global threat and has been identified as a crucial factor affecting South Africa s economy. Unemployment rate is one of the key indicators of South Africa s economy and reports by Statistics South Africa have indicated an increase in the unemployment rate. Studies done by the International Labour Organisation (ILO) has ranked South Africa amongst the worst in the world for unemployment and that poverty manifests not as a financial indicator but as a result of lack of employment opportunities. In response to the challenge of unemployment, South Africa has introduced numerous policies and strategies to combat unemployment and alleviate poverty. The vision of the Expanded Public Works Programme (EPWP) is to assist South Africa with its challenge of poverty eradication and to ease the unemployment statistics while simultaneously promoting skills development for its participants and the main focus of this policy is to provide income relief for the unemployment. The aim of this research was to assess the impact of EPWP in alleviating unemployment in Grahamstown, by assessing whether or not the EPWP has had any significant influence on job creation and skills development. This study focused on programmes implemented during the period 2014-2017 which is under phase 3 of the EPWP. This study adopted a qualitative research method and followed a descriptive approach. The research method did not seek to prove a true cause-effect relationship between the variables but rather demonstrate the correlation by means of case studies, archival research and content analysis. The research results revealed the potential of the EPWP projects in job creation in the area, and that there are areas of development and challenges in order to achieve the overall purpose of the EPWP.
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  • Date Issued: 2020

The role of the flower-galling mite, Aceria lantanae, in integrated control of the light pink 163LP variety of Lantana camara (L.) in South Africa:

  • Authors: Mukwevho, Ludzula , Mphephu, Tshililo E
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/149010 , vital:38795 , https://doi.org/10.1016/j.biocontrol.2020.104309
  • Description: We evaluated the impact of the gall-forming mite, Aceria lantanae (Cook) (Acari: Trombidiformes: Eriophyidae) on flower and fruit production by coppicing shoots, following pruning, of a widely distributed variety (light pink 163LP) of Lantana camara L. (Verbenaceae) in South Africa. Counts, at three different sites, of developed inflorescences, flowers and fruits and the extent of A. lantanae galling were done for coppicing shoots at four different stages of growth (3, 6, 9- and 12-months post-pruning).
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  • Date Issued: 2020

The Role of the Mnquma Local Municipality in Addressing Xenophobic Tensions between Foreign Shop Owners and Local Community Members in South Africa: A case study of Butterworth; 2010-2012

  • Authors: Ndinisa, Sibongile
  • Date: 2020
  • Subjects: Xenophobia Foreign workers
  • Language: English
  • Type: Thesis , Masters , MSoc (Political Science)
  • Identifier: http://hdl.handle.net/10353/18221 , vital:42243
  • Description: The study examines the role played by the Mnquma Local municipality in addressing xenophobic violence in Butterworth between 2010 and 2012 and subsequent sporadic tensions. The study also examines the causes as well as the sporadic recurrence of xenophobic tensions between foreign shop owners and local community members in Butterworth. Due to the nature of the study, ethnographic fieldwork was considered the most practical and suitable method in getting necessary responses regarding the study. The data collection instruments used were in-depth interviews and focus group discussions. Participants comprised 15 foreign shop owners, 15 local community members. In addition, three interviews were conducted with relevant Mnquma Local Municipality officials who had been involved in addressing xenophobic tensions in Butterworth. In order to understand the dynamics of xenophobic tensions in Butterworth, the study employed two theories; the Scapegoating theory and Relative Deprivation theory. The study established that the causes of xenophobic tensions were largely due to the poor socio-economic situation in the Mnquma Municipality, which resulted in high rates of poverty, unemployment and competition for resources and business opportunities. Furthermore, misinformation on media platforms about foreign nationals and the inadequate opportunities for interaction also exacerbated tensions. Moreover, it was uncovered that the Mnquma Local Municipality did not have effective mechanisms to address xenophobic tensions. The study recommends that the municipality addresses service delivery needs of both locals and foreign nationals as this will create a safe and peaceful environment for foreign nationals to coexist with locals in Butterworth. x The study further urges the Mnquma Local Municipality to formulate an antixenophobia unit that can detect and combat any sign of xenophobia in all communities in Butterworth.
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  • Date Issued: 2020

The roles of phonological awareness, rapid automatised naming and morphological awareness in isiXhosa:

  • Authors: Schaefer, Maxine , Probert, Tracy N , Rees, Siȃn
  • Date: 2020
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/159950 , vital:40359 , https://doi.org/10.5785/36-1-878
  • Description: The current paper examines the unique contributions of phonological awareness (PA), rapid automatised naming (RAN) and morphological awareness (MA) to oral reading fluency (ORF) in isiXhosa. No published study has yet explored the individual contributions of these three cognitive-linguistic skills to reading in isiXhosa. Sixty-six grade 3 home language isiXhosa learners were assessed on these cognitive-linguistic skills. Results from a linear regression analysis showed that only RAN and MA, but not PA, were significant concurrent predictors of ORF. These results suggest that the role of PA in reading in grade 3 learners in isiXhosa may have been overestimated because other important predictors of reading have not been controlled. Our data also suggest that grade 3 isiXhosa learners may make use of the morpheme as a grain size in reading. Our study highlights the need for longitudinal research which explores the roles of PA, MA and RAN in reading development in order to inform reading pedagogy in isiXhosa and other Southern Bantu languages.
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  • Date Issued: 2020

The SAPS 3 score as a predictor of hospital mortality in a South African tertiary intensive care unit: A prospective cohort study

The small pelagic fishery of the Pemba Channel, Tanzania: what we know and what we need to know for management under climate change

The social dimensions of biological invasions in South Africa

  • Authors: Shackleton, Ross T , Novoa, Ana , Shackleton, Charlie M , Kull, Christian A
  • Date: 2020
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/176285 , vital:42681 , DOI 10.1007/978-3-030-32394-3
  • Description: This chapter examines current knowledge relating to the human and social dimensions of biological invasions in South Africa. We do so by advancing 12 propositions and examining the evidence for or against each using South African literature. The propositions cover four broad issues: how people cause invasions; how they conceptualise them; effects of invasive species on people; and peoples’ responses to them.
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  • Date Issued: 2020

The social dimensions of biological invasions in South Africa

  • Authors: Shackleton, Ross T , Novoa, A , Shackleton, Charlie M
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , book chapter
  • Identifier: http://hdl.handle.net/10962/434000 , vital:73020 , ISBN 978-3-030-32394-3 , https://doi.org/10.1007/978-3-030-32394-3
  • Description: This chapter examines current knowledge relating to the human and social dimensions of biological invasions in South Africa. We do so by advancing 12 propositions and examining the evidence for or against each using South African literature. The propositions cover four broad issues: how people cause invasions; how they conceptualise them; effects of invasive species on people; and peoples’ responses to them. The propositions we assess include:(1) intentional introductions were and continue to refiect the social ethos of the time;(2) people go to great lengths to ensure that newly introduced species establish themselves;(3) human-mediated modifications help invasive species to establish;(4) how people think about and study invasive species is strongly shaped by social-ecological contexts;(5) knowledge and awareness of invasive species is low amongst the general public;(6) personal values are the primary factor affecting perceptions of invasive alien species and their control;(7) specific social-ecological contexts mediate how invasive species affect people;(8) research on social effects of invasive species primarily focuses on negative impacts;(9) the negative social impacts of invasive species on local livelihoods are of more concern to people than impacts on biodiversity;(10) people are less willing to manage species regarded as ‘charismatic’;(11) social heterogeneity increases confiicts around the management of biological invasions; and (12) engagement with society is key to successful management. By advancing and questioning propositions, we were able to determine what is known, provide evidence for where gaps lie, and thus identify areas for future research.
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  • Date Issued: 2020

The Socio-Economics of boat-based whale-watching in Plettenberg Bay

  • Authors: Klaas, Zongezile
  • Date: 2020
  • Subjects: Whale watching -- South Africa -- Western Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/48676 , vital:41058
  • Description: Boat-based whale watching has been gaining momentum since its inception back in the 1950s. Global trends of the marine leisure activity continue to grow at a rapid rate and the African continent has also joined the marine tourism trend in exploring its marine sector to meet its socio-economic challenges. South Africa as one of Africa’s economic giants has also sought a development approach with a focus on utilising its marine and maritime resources to grow the economy in meeting the domestic development objectives. The South African government through the Operation Phakisa come up with a development strategy to revitalise and explore its marine and maritime sectors to fast-track its growth potential in meeting the local developmental objectives. Plettenberg Bay in the Western Cape of South Africa is well-known for its boat-based whale watching service that offers a great experience for both domestic and foreign tourists and its services form part of the Operation Phakisa programme that is aimed at economic growth and development that is focused especially on the previously disadvantaged majority to ensure that their standards of living improve. Looking into the socio-economic effects of boat-based whale watching on low-income households in Plettenberg Bay, gives meaning to finding linkages through indirect relationships between the marine environment and human lives. This therefore fosters an in-depth understanding of how to address social and economic issues in relation to a resource through the utilisation of available assets to meet sustainable development objectives. The aim of the research study is to find the linkages between boat-based whale watching as an industry with how it relates to building resilience for the low-income households in Plettenberg Bay. The study’s importance will be its ability to inform policy decisions, on adopting knowledge-based adaptive strategies and approaches to finding solutions on building resilience for low-income household through the utilisation of boat-based whale watching as a catalyst for development. The information from the research study can be utilised as a tool to empower low-income households on coastal areas, to become active participants in economic activities that are indirectly linked to boat-based whale watching industry for their own development.
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  • Date Issued: 2020

The South African income tax implications of a Stokvel

  • Authors: Matshego, Katlego
  • Date: 2020
  • Subjects: Rotating credit associations -- South Africa. , Taxation -- South Africa , Tax deductions -- South Africa
  • Language: English
  • Type: text , Thesis , Masters , MCom
  • Identifier: http://hdl.handle.net/10962/143094 , vital:38201
  • Description: The term “Stokvel” originates from the rotating cattle auctions of English settlers in the Eastern Cape during the nineteen century. A Stokvel is defined as a credit union where a group of people agree to contribute a fixed amount of money to a common pool and is referred to as a rotating savings and credit association, where the contributions to a fund are given in whole or in part to each member. The goal of the thesis was to determine the “gross income” implications of the fund and its members, as well the deductibility of their expenses. An interpretative research approach was used in the research as it sought to understand and describe. No interviews were conducted for this research and the data used for the research are publicly available. The tax implications of five different types of a Stokvel were considered in relation to the research goals through the application of legislation and case law principles. The study established that a collection burial society, where funds are contributed after death, does not beneficially receive funds and it is not entitled to any deductions. The same applies to the member of that society. A contributing burial society, where funds are contributed over time, beneficially receives funds, which are included in “gross income”, and qualifies for deductions. The receipt by the member is exempt and deductions are prohibited by section 23(f). An entertainment Stokvel does not receive the contributions on its own behalf and benefit. No deductions are available to it. However, the member beneficially receives the contributions from the Stokvel, which are included in “gross income”, and qualifies for deductions. A purchasing power group, where items are purchased on behalf of members, does not receive the funds beneficially and no deductions are available to it. The members simply receive the goods they have paid for. Lastly an investment Stokvel, which invests contributions for the members, beneficially receives contributions and qualifies for various deductions. The member receives the share of income from the Stokvel for his/her own benefit. However, no deductions are available in respect of contributions.
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  • Date Issued: 2020

The spatiotemporal aspects of predation on the Cape gannet Morus capensis population at the Lambert’s Bay gannet colony, Western Cape, South Africa

  • Authors: Schoeman, Zanri
  • Date: 2020
  • Subjects: Sea birds -- South Africa -- Western Cape
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/47656 , vital:40262
  • Description: Seabirds are one of the most threatened groups of birds with 29% of seabird species at some risk of extinction. As a result of multiple human-induced threats, seabird species including the Cape gannet Morus capensis which is endemic to southern Africa population experience significant declines and is now classified as Endangered. The Cape gannet faces predation threats from a variety of different species. The current predators of concern at Lambert’s Bay gannet colony are both the Cape fur seal Arctocephalus pusillus pusillus and the Kelp gull Larus dominancus. The former predates on fledglings and the latter predates on eggs. In the 2005/06 breeding season the entire Cape gannet population deserted the Lambert’s Bay gannet colony due to predation by the Cape fur seal. Although the Cape gannets have subsequently recovered to approximately 8000 pairs, seal predation on Cape gannet fledglings continues, together with predation by Kelp gulls. This has caused concern over the impact of predation on this species at the Lambert’s Bay colony, particularly given the species’ conservation status, its small breeding range and its current population trend. CapeNature, the conservation agency involved at this colony has been monitoring and managing the predation on Cape gannets and are interested in evaluating the success of their efforts. Therefore the aim of this study was to determine the spatial and temporal aspects of predation on the Cape gannet population at Lambert’s Bay gannet colony. When examining the influence of fish availability on predation intensity, we found that in years with an increase in fish biomass there was a decrease in predation probability by Cape fur seals. This increase in fish biomass not only led to decreased predation on the fledglings it also led to increased breeding success of the Cape gannets. In determining the effect of predation within the Cape gannet breeding colony we found that the probability of predation by Kelp gulls decreased in years with increased adult gannet density. Indirectly, Cape gannet population growth should lead to a decrease in Kelp gull predation as a higher gannet density increases the risk of injury to the Kelp gulls. This suggests that if Cape gannet populations continue to decline, they may become increasingly vulnerable to Kelp gull predation which can result in a further population decline. In terms of past management actions, the selective culling of predatory Cape fur seals and Kelp gulls, was evaluated. It was found that in the years in which culling of Cape fur seals and Kelp gulls was implemented, a decrease in predation was observed. This indicated that culling reduced predation in the short-term. Predation is inevitable, but due to the Cape gannet’s conservation status we suggest that additional, long-term, and more sustainable methods to reduce predation should be explored. Our research emphasises the need for improving food availability to Cape gannets as food security is paramount to their long-term survival and population growth. Colony management in isolation from other management strategies, is not efficient for conserving a species. We therefore suggest that sound management of predation at the terrestrial habitats are required but that effective management of fisheries are also required for the successful conservation of the Cape gannet. Food security for Cape gannets could be improved by, for example, establishing some ways that we suggest improving the food security for Cape gannets would be to establish Marine Protected Areas (MPAs) with dynamic boundaries around Cape gannet colonies, and to have locate the MPAs close to breeding and foraging hotspots where these areas are closed to fishing thus reducing the competition between commercial fisheries and marine predators, such as the Cape gannet. Another way to improve food security for the gannets are to promote the efforts of focussing on developing and implementing an ecosystem approach to fisheries management in which fishing quotas account for the needs of marine predators. The findings of this study have not only aided the understanding of the dynamics of predation on the Cape gannets and highlighted the extent that predation takes place on them but can also guide future management decisions regarding predation on this endemic and endangered species.
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  • Date Issued: 2020

The taxonomic status of dolphins Tursiops spp. and Delphinus in South African waters

  • Authors: Ngqulana, Sibusisiwe Gloria
  • Date: 2020
  • Subjects: Dolphins -- Classification -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/48566 , vital:40891
  • Description: There is a need for identifying important sites, taxonomic units or populations and the usual criterion used is species identification. The species is the most important taxonomic unit to define in taxonomy, as it is the primary unit of concern in biodiversity, conservation and other biological issues. Thus, taxonomy plays an important role in conservation biology. Additionally, taxonomy can contribute to the development of analytical systems that will provide information on priorities for reaching defensible targets for established conservation. This poses a problem for cetaceans as basic information is frequently deficient and therefore not suitable for conservation planning purposes. This leads to difficulties in identifying and prioritizing areas for the monitoring, management and for the protection of species or populations. Morphological and geographic data used to be the primary means used by taxonomists to define species and subspecies, and due to this, most extant species have been classified by morphological characteristics. However, in the recent years, molecular analyses have been introduced and subsequently stable isotopes were also included to assist in interpreting results. Thereafter, it became a common approach to use more than one technique or a combination of independent datasets to resolve taxonomic uncertainties. This has resulted to a proposed term known as integrative taxonomy. Integrative taxonomy has recently been used in most studies that deal with taxonomy or population structure. The use of multiple lines of evidence, which is sometimes referred to as integrative taxonomy, raises the level of confidence in clearly delineating species. Cetaceans are the most taxonomically diverse group of aquatic mammals, with 93 living species accepted. Previously, their taxonomy was based on morphological characters. However, cetaceans have recently been subjected to intense phylogenetic investigations using both morphological and molecular data. These problems are not only prevalent in larger whales, but the small toothed whales also have these challenges, particularly family Delphinidae. This family is known to be the most diverse among the toothed whales. This is because this family diverged recently, and the divergence occurred relatively fast. This study aimed to clarify the taxonomic status of Tursiops spp. and Delphinus in the family Delphinidae, inhabiting the South African waters, using a combination of morphological and molecular methods. For skull morphology, geometric morphometrics were used, while for molecular methods, the D-loop region in the mitochondrial DNA was used to detect any differences within each genus. For the genus Tursiops, this study showed the consistency of results in all analyses used to investigate the presence of two species in the genus Tursiops in South African waters. This study only analysed sequences from the mitochondrial D-loop region and has re-confirmed the presence of the two species in South Africa. Skull and external morphology both show T. truncatus to be bigger and more robust, and to have a shorter rostrum compared with T. aduncus. These external observations are helpful when identifying the species in the field. Providing evidence supporting the presence of two Tursiops species in South Africa does not only contribute to the global context of the taxonomy of this genus, but also in the local context. This study also gives insight on the distribution of the two species in the region. For the genus Delphinus, molecular analysis did not reveal any clustering in South African Delphinus specimens, which suggested a single species, D. delphis, and that this species is morphologically highly variable. Both skull and external morphology did not reflect the molecular results, supporting suggestions that morphology in this genus does not reflect genetic differences. It has been shown that morphological variation reflects feeding specialization rather than speciation. This may also reflect local adaptations. Both skull and external morphology in this study showed no significant differences. This study did not investigate the phylogeographic details of the species in South Africa and further molecular work including a larger sample size from the west coast of South Africa is needed. By attempting to unravel the taxonomy of these dolphins in South African waters, the findings of this study will be very useful in the development of effective conservation and management strategies for these dolphins.
  • Full Text:
  • Date Issued: 2020

The Thousand-Pulsar-Array programme on MeerKAT–I: science objectives and first results

The Transformative Power of Language: From Postcolonial to Knowledge Societies in Africa

  • Authors: Kaschula, Russell H , Wolff, H Ekkehard
  • Date: 2020
  • Language: English
  • Type: text , book
  • Identifier: http://hdl.handle.net/10962/174514 , vital:42484 , ISBN 9781108498821
  • Description: Language has played a pivotal role in societal transformation in postcolonial Africa towards the creation of globally competitive knowledge societies; however so far, this role has been under-researched and under-estimated. This volume addresses this gap in the literature, by bringing together a team of globally-recognised scholars to explore the effect of language on African postcolonial societies, and how it has contributed to achieving 'mental decolonisation'. A range of languages are explored, both imported (ex-colonial) and indigenous African, and case studies from different spheres of public discourse are investigated, from universities to legal settings. Demonstrating that multilingualism is a resource for, rather than barrier to, successful transformation, this book brings the intellectualisation and institutionalisation of African languages to the forefront of development discourse, and provides an insightful snap-shot of how current academic research, public discourse, political activism and social community engagement have contributed to societal transformation in South Africa.
  • Full Text:
  • Date Issued: 2020

The Unintended Consequences of Using Direct Incentives to Drive the Complex Task of Research Dissemination

  • Authors: Muthama, Evelyn , McKenna, Sioux
  • Date: 2020
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/187116 , vital:44569 , xlink:href="https://doi.org/10.25159/1947-9417/6688"
  • Description: Universities have used an array of incentives to increase academic publications, which are highly rewarded in the South African higher education funding formula. While all universities use indirect incentives, such as linking promotion and probation to publication, the mechanisms used in some institutions have taken a very direct form, whereby authors are paid to publish. This process has paralleled a large rise in publication outputs alongside increased concerns about quality. Significantly, there are ethical questions to be asked when knowledge dissemination is so explicitly linked to financial reward through the payment of commission to academics. Based on an analysis of institutional policies and data from an online survey and interviews with academics from seven South African universities, we argue that when money is the main means used to encourage academics to contribute to knowledge, numerous unintended consequences may emerge. These include a focus on quantity rather than the quality of research, a rise in predatory publishing, and resentment among academics. We argue that incentives, in particular direct payment for publications, undermine the academic project by positioning publications in terms of exchange-value rather than their use-value as a contribution to knowledge building.
  • Full Text:
  • Date Issued: 2020
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