Exploring feeding ecology and population growth rate responses of ungulates in Southern African arid biomes
- Authors: Vermeulen, Mika Margaret
- Date: 2017
- Subjects: Ungulates -- South Africa Arid regions -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/15237 , vital:28189
- Description: Limited resources, extreme temperatures and predators are some of the stresses that are faced by ungulates in arid biomes. Understanding how these stressors influence ungulate feeding ecology and population growth rates is important for managers, as these could influence the persistence of ungulates in protected areas. An understanding of these stressors is especially relevant given the significant population declines in ungulate species globally. The Nama Karoo biome and the arid Savanna, an arid form of the Savanna biome, are both arid, but have distinct rainfall seasonality and vegetation structure and represent unique characteristics that need to be properly considered in their own regard. The literature on African ungulate feeding ecology covers a range of species and biomes from southern and east Africa, however, very little is known about ungulate dietary preferences in the Nama Karoo. Unexplained population declines in springbok (Antidorcas marsupialis) and red hartebeest (Alcelaphus buselaphus caama) have occurred at local scales across the Nama Karoo and the arid Savanna, most notably springbok population declines at the Karoo National Park (Karoo NP). This study sought to improve the understanding of ungulate feeding ecology and population growth rate responses in two arid biomes of South Africa. To achieve this, ungulate dietary composition was characterised, in terms of the proportional seasonal contribution of C4 and C3 plant forms, of a range of ungulates in the Nama Karoo, at the Karoo NP and the arid Savanna, at the Tswalu Kalahari Reserve (Tswalu KR), using stable carbon isotope analysis. Fresh faecal samples of ungulate species were collected from both the biomes during the dry, early wet and late wet seasons. Species were categorised per biome into feeding guilds and the effects of season, biome and the interaction thereof on the diets of the ungulate species explored. Furthermore, the findings were interpreted against what is known about diets of the respective species elsewhere in southern and east Africa. Secondly, trends in ungulate population growth rates were assessed within the Karoo NP and the Tswalu KR over the past 12 and14 years respectively. Furthermore, the variables influencing ungulate population growth rates (and generality of trends), with emphasis on ungulate biomass and rainfall, were explored at biome and species level. Population size data were obtained from annual aerial censuses for the period 2002-2015 and used to calculate annual growth rates and biomass for each ungulate species. The contribution of C4 forage to the diets of ungulate species in the arid Savanna was generally higher than in the Nama Karoo,in line with greater relative abundance of C4 grasses in the former. During winter (dry season) C3 intake was higher in the Nama Karoo than in the arid Savanna, reflecting C3 plant growth (C3 grasses and shrubs) and rainfall during winter in the Nama Karoo. Mean population growth rates during the study period were negative in some of the threatened species considered, i.e. mountain reedbuck (Redunca fulvorufula fulvorufula), tsessebe (Damaliscus lunatus lunatus) and Hartmann’s mountain zebra (Equus zebra hartmannae). No evidence for negative density dependent regulation (~intra-/interspecific competition) of ungulate population growth rates was found, whereas bottom up (~rainfall) and positive density dependent (~biomass of the species under investigation) regulatory mechanisms were most influential. The rainfall and biomass variables influenced the population growth rates of smaller ungulate species more than those of larger bodied ungulate species. Knowledge of ungulate diets will enable managers of protected areas to better understand how climate change, and resultant changes in relative abundances of plant growth forms, will influence specific ungulate species. The finding that increased population biomass positively influenced certain ungulate species’ growth rates has potential implications for management intervention as ungulate biomass is a variable that can be manipulated in protected areas. The reinforcement of existing mountain reedbuck, springbok and red hartebeest populations, specifically, at the Karoo NP and the Tswalu KR may counter their current negative growth rates in these two protected areas. Finally, the influence of protected area size and fencing, on ungulate vulnerability to predators (~top down) and forage quality (~bottom up) mechanisms in arid biomes needs to be further explored.
- Full Text:
- Date Issued: 2017
- Authors: Vermeulen, Mika Margaret
- Date: 2017
- Subjects: Ungulates -- South Africa Arid regions -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/15237 , vital:28189
- Description: Limited resources, extreme temperatures and predators are some of the stresses that are faced by ungulates in arid biomes. Understanding how these stressors influence ungulate feeding ecology and population growth rates is important for managers, as these could influence the persistence of ungulates in protected areas. An understanding of these stressors is especially relevant given the significant population declines in ungulate species globally. The Nama Karoo biome and the arid Savanna, an arid form of the Savanna biome, are both arid, but have distinct rainfall seasonality and vegetation structure and represent unique characteristics that need to be properly considered in their own regard. The literature on African ungulate feeding ecology covers a range of species and biomes from southern and east Africa, however, very little is known about ungulate dietary preferences in the Nama Karoo. Unexplained population declines in springbok (Antidorcas marsupialis) and red hartebeest (Alcelaphus buselaphus caama) have occurred at local scales across the Nama Karoo and the arid Savanna, most notably springbok population declines at the Karoo National Park (Karoo NP). This study sought to improve the understanding of ungulate feeding ecology and population growth rate responses in two arid biomes of South Africa. To achieve this, ungulate dietary composition was characterised, in terms of the proportional seasonal contribution of C4 and C3 plant forms, of a range of ungulates in the Nama Karoo, at the Karoo NP and the arid Savanna, at the Tswalu Kalahari Reserve (Tswalu KR), using stable carbon isotope analysis. Fresh faecal samples of ungulate species were collected from both the biomes during the dry, early wet and late wet seasons. Species were categorised per biome into feeding guilds and the effects of season, biome and the interaction thereof on the diets of the ungulate species explored. Furthermore, the findings were interpreted against what is known about diets of the respective species elsewhere in southern and east Africa. Secondly, trends in ungulate population growth rates were assessed within the Karoo NP and the Tswalu KR over the past 12 and14 years respectively. Furthermore, the variables influencing ungulate population growth rates (and generality of trends), with emphasis on ungulate biomass and rainfall, were explored at biome and species level. Population size data were obtained from annual aerial censuses for the period 2002-2015 and used to calculate annual growth rates and biomass for each ungulate species. The contribution of C4 forage to the diets of ungulate species in the arid Savanna was generally higher than in the Nama Karoo,in line with greater relative abundance of C4 grasses in the former. During winter (dry season) C3 intake was higher in the Nama Karoo than in the arid Savanna, reflecting C3 plant growth (C3 grasses and shrubs) and rainfall during winter in the Nama Karoo. Mean population growth rates during the study period were negative in some of the threatened species considered, i.e. mountain reedbuck (Redunca fulvorufula fulvorufula), tsessebe (Damaliscus lunatus lunatus) and Hartmann’s mountain zebra (Equus zebra hartmannae). No evidence for negative density dependent regulation (~intra-/interspecific competition) of ungulate population growth rates was found, whereas bottom up (~rainfall) and positive density dependent (~biomass of the species under investigation) regulatory mechanisms were most influential. The rainfall and biomass variables influenced the population growth rates of smaller ungulate species more than those of larger bodied ungulate species. Knowledge of ungulate diets will enable managers of protected areas to better understand how climate change, and resultant changes in relative abundances of plant growth forms, will influence specific ungulate species. The finding that increased population biomass positively influenced certain ungulate species’ growth rates has potential implications for management intervention as ungulate biomass is a variable that can be manipulated in protected areas. The reinforcement of existing mountain reedbuck, springbok and red hartebeest populations, specifically, at the Karoo NP and the Tswalu KR may counter their current negative growth rates in these two protected areas. Finally, the influence of protected area size and fencing, on ungulate vulnerability to predators (~top down) and forage quality (~bottom up) mechanisms in arid biomes needs to be further explored.
- Full Text:
- Date Issued: 2017
The relationship between values-based leadership and employee engagement
- Authors: Simon, Bridgette Virginia
- Date: 2017
- Subjects: Leadership -- South Africa Employee motivation -- South Africa , Management -- Employee participation -- South Africa Organizational effectiveness -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/20220 , vital:29159
- Description: Sustaining competitiveness requires organisations to continuously reinvent themselves, consider both external influences as well as internal risk that may affect the company as a market leader. Organisations that have acknowledged that a relationship between engaged employees and business success exists, would seek ways to foster and facilitate the engagement of their workers through their leadership. The primary objective of the study was to determine whether a relationship exists between values-based leadership and employee engagement. The aim was to contribute to the quality of leadership values, behaviour and influence at Coca-Cola Beverages South Arica by gaining a deeper understanding of leadership and employee engagement. The theoretical study explored the definitions, key concepts, benefits and outcomes of both values based leadership and employee engagement. It provided a detailed literature review of the role of leadership in creating a values based organisation, what values-based leadership encompasses and its relationship with employee engagement. The theoretical overview highlighted that leadership is an influential factor in employee engagement and the extent to which employees feel valued and connected to the organisation’s goals. The theoretical overview further confirmed that leadership values, behaviour and influence are interrelated and exert an influence on employee engagement, thereby strengthening the fact that there is a relationship between values-based leadership and employee engagement. A structured web-based survey, with a questionnaire, was used to corroborate the theoretical findings and to assess employees’ perceptions of the prevalence of values–based leadership and employee engagement. A sample of 269 respondents was selected to participate in the empirical study and 167 responded to the survey, which yielded a 62% per cent response rate. The key findings of the study indicate that strong correlations exist between leadership values, behaviours and influence and that these concepts were interrelated. Furthermore, the study confirmed that values–based leadership was an important factor in employee engagement and specifically in terms of the physical, emotional and social components of engagement and less so in terms of the cognitive component. Values-based leadership and engagement were identified as critical factors in ensuring that organisations are well equipped to deal with the current volatile economic environment and to consider ways to maintain and accelerate their profitability and competitiveness in order to remain a sustainable business. It is strong values that underpin the performance of highly successful and sustainable organisations; coupled with effective leadership as a key driving force.
- Full Text:
- Date Issued: 2017
- Authors: Simon, Bridgette Virginia
- Date: 2017
- Subjects: Leadership -- South Africa Employee motivation -- South Africa , Management -- Employee participation -- South Africa Organizational effectiveness -- South Africa
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/20220 , vital:29159
- Description: Sustaining competitiveness requires organisations to continuously reinvent themselves, consider both external influences as well as internal risk that may affect the company as a market leader. Organisations that have acknowledged that a relationship between engaged employees and business success exists, would seek ways to foster and facilitate the engagement of their workers through their leadership. The primary objective of the study was to determine whether a relationship exists between values-based leadership and employee engagement. The aim was to contribute to the quality of leadership values, behaviour and influence at Coca-Cola Beverages South Arica by gaining a deeper understanding of leadership and employee engagement. The theoretical study explored the definitions, key concepts, benefits and outcomes of both values based leadership and employee engagement. It provided a detailed literature review of the role of leadership in creating a values based organisation, what values-based leadership encompasses and its relationship with employee engagement. The theoretical overview highlighted that leadership is an influential factor in employee engagement and the extent to which employees feel valued and connected to the organisation’s goals. The theoretical overview further confirmed that leadership values, behaviour and influence are interrelated and exert an influence on employee engagement, thereby strengthening the fact that there is a relationship between values-based leadership and employee engagement. A structured web-based survey, with a questionnaire, was used to corroborate the theoretical findings and to assess employees’ perceptions of the prevalence of values–based leadership and employee engagement. A sample of 269 respondents was selected to participate in the empirical study and 167 responded to the survey, which yielded a 62% per cent response rate. The key findings of the study indicate that strong correlations exist between leadership values, behaviours and influence and that these concepts were interrelated. Furthermore, the study confirmed that values–based leadership was an important factor in employee engagement and specifically in terms of the physical, emotional and social components of engagement and less so in terms of the cognitive component. Values-based leadership and engagement were identified as critical factors in ensuring that organisations are well equipped to deal with the current volatile economic environment and to consider ways to maintain and accelerate their profitability and competitiveness in order to remain a sustainable business. It is strong values that underpin the performance of highly successful and sustainable organisations; coupled with effective leadership as a key driving force.
- Full Text:
- Date Issued: 2017
Fostering corporate citizenship in the South African taxi industry
- Authors: Peko, Nyameka
- Date: 2015
- Subjects: Corporations -- South Africa -- Nationality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/2869 , vital:20358
- Description: The purpose of this study was to investigate and foster corporate citizenship (CC) in the SA taxi industry. The primary objective of this study was to foster corporate citizenship in the South African taxi industry by investigating the determinants that would increase CC in the SA taxi industry. The study gathered quantitative information about CC, identified which factors influence CC in the taxi industry and investigated which of these factors are the most important determinants that would increase the CC in the industry in South Africa. This study was intended to contribute to building the body of knowledge for the implementation and fostering of corporate citizenship programs. In particular, the researcher hoped that the framework provided in this study would outline the practical strategies that the taxi organisations should take in developing targeted, long-term partnerships with the communities in which they operate. Convenience sampling was used to select one hundred (100) participants. The response rate was ninety-six percent (96%). The sample was structured to include the directors, deputy directors, senior managers, managers and the drivers of the taxi organisations in twenty-three districts in the Eastern Cape. These participants were taken from the body that incorporates all the taxi associations in Eastern Cape called the Eastern Cape Bus and Business Chamber (ECBTBC). The empirical results revealed that in order to increase corporate citizenship within the SA taxi industry there should be an increase in its human resource management, operations management and the dynamic externalism of its members. The findings also revealed that the social cynicism should be decreased within this industry.
- Full Text:
- Date Issued: 2015
- Authors: Peko, Nyameka
- Date: 2015
- Subjects: Corporations -- South Africa -- Nationality
- Language: English
- Type: Thesis , Masters , MBA
- Identifier: http://hdl.handle.net/10948/2869 , vital:20358
- Description: The purpose of this study was to investigate and foster corporate citizenship (CC) in the SA taxi industry. The primary objective of this study was to foster corporate citizenship in the South African taxi industry by investigating the determinants that would increase CC in the SA taxi industry. The study gathered quantitative information about CC, identified which factors influence CC in the taxi industry and investigated which of these factors are the most important determinants that would increase the CC in the industry in South Africa. This study was intended to contribute to building the body of knowledge for the implementation and fostering of corporate citizenship programs. In particular, the researcher hoped that the framework provided in this study would outline the practical strategies that the taxi organisations should take in developing targeted, long-term partnerships with the communities in which they operate. Convenience sampling was used to select one hundred (100) participants. The response rate was ninety-six percent (96%). The sample was structured to include the directors, deputy directors, senior managers, managers and the drivers of the taxi organisations in twenty-three districts in the Eastern Cape. These participants were taken from the body that incorporates all the taxi associations in Eastern Cape called the Eastern Cape Bus and Business Chamber (ECBTBC). The empirical results revealed that in order to increase corporate citizenship within the SA taxi industry there should be an increase in its human resource management, operations management and the dynamic externalism of its members. The findings also revealed that the social cynicism should be decreased within this industry.
- Full Text:
- Date Issued: 2015
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