Predicting reintroduction outcomes: assessing the feasibility of reintroducing African wild dog to a small protected area
- Authors: Vogel, John Thomas
- Date: 2018
- Subjects: African wild dog , Wild dogs -- South Africa Wild dogs -- Conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/36464 , vital:33947
- Description: Large mammalian carnivores have experienced significant contractions in population sizes and geographical ranges. The conservation of large carnivores is crucially important, particularly due to their vulnerability to extinction and their functional significance and ability to structure ecosystems. Due to an expanding human footprint, large carnivores are increasingly subject to modified and spatially constrained habitats. A growing debate exists as to how to conserve and coexist with large carnivores in an anthropogenically induced environment. Reintroduction, as a conservation tool to restore locally extirpated large carnivores to portions of their former ranges is increasingly being applied. However, in South Africa, habitat to support large carnivores remain small and non-contiguous. Food is a fundamental ecological requirement to sustain reintroduced large carnivores. Therefore, an understanding of large predator foraging patterns can be informative in the context of how the predator species influences and utilises a novel ecosystem. We investigated the foraging behaviour of reintroduced African wild dog (Lycaon pictus) at five small protected areas in KwaZulu-Natal, South Africa. Wild dog utilised 16 prey species, albeit they primarily used nyala (Tragelaphus angasii) and impala (Aepyceros melampus) which collectively form 75 % of their diet. Only nyala was significantly preferred, suggesting that this prey species is used in greater proportion to their abundance. As wild dogs are social cooperative hunters, we tested whether wild dog pack size was correlated to prey mass selection. There was no evidence to suggest that larger packs use larger prey. However, the mean wild dog pack size in our sample sites, was relatively smaller than those encountered elsewhere. Furthermore, wild dog have been shown to modify their hunting behaviour in the presence of wildlife-proof fencing, by using fences to aid in the capture of larger prey species than would innately occur. We compared the prey mass of wild dog kills in relation to proximity of these hard boundaries. Despite the affinity towards kills occurring within 200 m of fences, the upward bias caused by fences on prey mass selection was inconsistent across sample sites. The relatively small size of wild dogs makes them particularly vulnerable to competition. As the energetic output of wild dog is high, interspecific competition can increase foraging costs. The reintroduction of large carnivores to small artificially induced systems may be a contentious issue as resources available to support large carnivores are expected to be relatively more finite. We compared both the potential inter- and intraspecific dietary niche dimensions of an intact large carnivore guild in context of a wild dog reintroduction. We determined cheetah (Acinonyx jubatus), leopard (Panthera pardus), and lion (Panthera leo) prey composition, diet breadth, overlap, prey preference and predicted the density of an intact large carnivore guild in a novel landscape. Further, we compared the foraging behaviour of these large carnivores to that of wild dog. Our findings suggest that large African carnivores in small protected areas are subject to a considerable dietary niche overlap. Wild dog and cheetah, particularly reproductive females with dependent offspring, displayed the greatest potential for dietary overlap and subsequent competition. Leopard and lion at the population species level exhibited greater degrees of foraging plasticity. Lion displayed a contrasting prey species preference to sympatric predators as they selected for prey items frequently avoided by cheetah, leopard and wild dog. The proposed wild dog reintroduction site is expected to sustain seven wild dog based on the availability of preferred prey biomass. However, the reintroduction of wild dog to the small protected area is expected to have negative lateral trophic influences on other species of conservation concern. This should be of vital importance to management of the protected area. As the influence of competition in food-web and population dynamics, particularly in resource poor environments may be profound, our research highlights the need to assess the influence of competitive forces in structuring and restoring large predators to portions of their historical range.
- Full Text:
- Date Issued: 2018
- Authors: Vogel, John Thomas
- Date: 2018
- Subjects: African wild dog , Wild dogs -- South Africa Wild dogs -- Conservation -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: http://hdl.handle.net/10948/36464 , vital:33947
- Description: Large mammalian carnivores have experienced significant contractions in population sizes and geographical ranges. The conservation of large carnivores is crucially important, particularly due to their vulnerability to extinction and their functional significance and ability to structure ecosystems. Due to an expanding human footprint, large carnivores are increasingly subject to modified and spatially constrained habitats. A growing debate exists as to how to conserve and coexist with large carnivores in an anthropogenically induced environment. Reintroduction, as a conservation tool to restore locally extirpated large carnivores to portions of their former ranges is increasingly being applied. However, in South Africa, habitat to support large carnivores remain small and non-contiguous. Food is a fundamental ecological requirement to sustain reintroduced large carnivores. Therefore, an understanding of large predator foraging patterns can be informative in the context of how the predator species influences and utilises a novel ecosystem. We investigated the foraging behaviour of reintroduced African wild dog (Lycaon pictus) at five small protected areas in KwaZulu-Natal, South Africa. Wild dog utilised 16 prey species, albeit they primarily used nyala (Tragelaphus angasii) and impala (Aepyceros melampus) which collectively form 75 % of their diet. Only nyala was significantly preferred, suggesting that this prey species is used in greater proportion to their abundance. As wild dogs are social cooperative hunters, we tested whether wild dog pack size was correlated to prey mass selection. There was no evidence to suggest that larger packs use larger prey. However, the mean wild dog pack size in our sample sites, was relatively smaller than those encountered elsewhere. Furthermore, wild dog have been shown to modify their hunting behaviour in the presence of wildlife-proof fencing, by using fences to aid in the capture of larger prey species than would innately occur. We compared the prey mass of wild dog kills in relation to proximity of these hard boundaries. Despite the affinity towards kills occurring within 200 m of fences, the upward bias caused by fences on prey mass selection was inconsistent across sample sites. The relatively small size of wild dogs makes them particularly vulnerable to competition. As the energetic output of wild dog is high, interspecific competition can increase foraging costs. The reintroduction of large carnivores to small artificially induced systems may be a contentious issue as resources available to support large carnivores are expected to be relatively more finite. We compared both the potential inter- and intraspecific dietary niche dimensions of an intact large carnivore guild in context of a wild dog reintroduction. We determined cheetah (Acinonyx jubatus), leopard (Panthera pardus), and lion (Panthera leo) prey composition, diet breadth, overlap, prey preference and predicted the density of an intact large carnivore guild in a novel landscape. Further, we compared the foraging behaviour of these large carnivores to that of wild dog. Our findings suggest that large African carnivores in small protected areas are subject to a considerable dietary niche overlap. Wild dog and cheetah, particularly reproductive females with dependent offspring, displayed the greatest potential for dietary overlap and subsequent competition. Leopard and lion at the population species level exhibited greater degrees of foraging plasticity. Lion displayed a contrasting prey species preference to sympatric predators as they selected for prey items frequently avoided by cheetah, leopard and wild dog. The proposed wild dog reintroduction site is expected to sustain seven wild dog based on the availability of preferred prey biomass. However, the reintroduction of wild dog to the small protected area is expected to have negative lateral trophic influences on other species of conservation concern. This should be of vital importance to management of the protected area. As the influence of competition in food-web and population dynamics, particularly in resource poor environments may be profound, our research highlights the need to assess the influence of competitive forces in structuring and restoring large predators to portions of their historical range.
- Full Text:
- Date Issued: 2018
The dispersal of African wild dogs (Lycaon Pictus) from protected areas in the Northern KwaZulu‐Natal Province, South Africa.
- Whittington‐Jones, Brendan Mark
- Authors: Whittington‐Jones, Brendan Mark
- Date: 2012
- Subjects: African wild dog , African wild dog -- Conservation -- South Africa -- KwazuluNatal , African wild dog -- Dispersal -- South Africa -- KwaZulu-Natal , African wild dog -- Effect of human beings on -- South Africa -- KwaZulu Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5893 , http://hdl.handle.net/10962/d1013414
- Description: The number of African wild dogs Lycaon pictus in Northern KwaZulu‐Natal, South Africa has increased substantially over the last six years. This is largely due to a managed metapopulation approach of introductions onto protected areas and private game reserves since 1998. Because of the increasing wild dog population, the likelihood of rural communities surrounding protected areas encountering dispersing wild dogs in northern KwaZulu‐Natal has also increased. Resident wild dog populations currently occur in Hluhluwe‐iMfolozi Park (HiP), Mkhuze Game Reserve (MGR) of Isimangaliso Wetland Park and Thanda Private Game Reserve (TPGR) all of which are bordered by a matrix of natural habitats and human settlements. Thus, land outside these protected areas could be utilized to expand wild dog distribution and provide connectivity between existing resident populations of wild dogs within KwaZulu‐Natal. To investigate the viability of such an approach, Maximum Entropy Modelling (Maxent) was used to characterize habitat niche selection of dispersing wild dogs, and to identify potential dispersal linkages between current wild dog metapopulation reserves. The model was calibrated using 132 location points collected from 2006 until 2009. From 2008 to 2009 I also conducted a survey of 247 community members in tribal authorities bordering HiP and MGR, to understand factors influencing attitudes towards wild dogs. A habitat suitability model with seven predictor variables had an AUC of 0.96 (SD = 0.02) and indicated four variables which best predicted probability of presence for dispersing wild dogs: elevation, road density, land cover and human density. The results suggest that elevation and land cover may be of greater influence for dispersing wild dogs than human density or activity. Elevation was the single most effective variable indicating a higher probability of presence for dispersing wild dogs in lower lying locations; peaking at approximately 200 – 300m a.s.l. Wild dogs also showed a preference for Woodland and Bushland habitats which in KwaZulu‐Natal tend to be found on lower lying topography. A preference for areas of lower human density and a highest probability of presence at road densities of approximately 0.7km/km2 or less would suggest that while wild dogs may show a tendency to avoid areas of high human activity, they can coexist in close proximity to humans. Respondent’s attitudes, knowledge of wild dogs and livestock husbandry were interpreted by the development of a set of indices. Attitudes were positively related to formal education levels and wild dog‐specific education, but were not influenced by demographic factors such as gender, age and employment status. Eighty three percent of respondents believed efforts to protect wild dogs should continue. Respondents with higher numbers of livestock tended to have more positive attitudes towards wild dogs despite generally incurring higher losses to carnivore depredation than those with less livestock. This appears to be because the financial burden of livestock losses to those with fewer livestock is perceived to be a loss of a greater proportion of total financial wealth. The study highlighted the substantial scope for improvement in livestock management. Theft (34 percent), drought (30 percent) and disease (14 percent) were ranked as the greatest problems facing livestock owners while predators were ranked as the greatest problem by only 4 percent of respondents. My findings suggest that wild dogs are generally viewed positively or with ambivalence. Concerns over the potentially increasing threat to livestock, as natural prey numbers outside protected areas decline and wild dogs disperse from natal packs, are likely to be manageable. However, wild dog population expansion within KwaZulu‐Natal will continue to rely on managed core populations on perimeter‐fenced metapopulation reserves with tolerant communities and landowners contributing to the connectivity of isolated reserves. Generation of tolerance can be instilled through continued advocacy and education, supported by conflict mitigation initiatives and rapid response to conflict reports. The implementation of incentive schemes for adjoining private landowners to co‐manage wild dog populations will need to be addressed in conjunction with managed metapopulation practices and law enforcement, to promote range expansion, and reduce potentially lethal edge effects and wild dog‐human conflict.
- Full Text:
- Date Issued: 2012
- Authors: Whittington‐Jones, Brendan Mark
- Date: 2012
- Subjects: African wild dog , African wild dog -- Conservation -- South Africa -- KwazuluNatal , African wild dog -- Dispersal -- South Africa -- KwaZulu-Natal , African wild dog -- Effect of human beings on -- South Africa -- KwaZulu Natal
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5893 , http://hdl.handle.net/10962/d1013414
- Description: The number of African wild dogs Lycaon pictus in Northern KwaZulu‐Natal, South Africa has increased substantially over the last six years. This is largely due to a managed metapopulation approach of introductions onto protected areas and private game reserves since 1998. Because of the increasing wild dog population, the likelihood of rural communities surrounding protected areas encountering dispersing wild dogs in northern KwaZulu‐Natal has also increased. Resident wild dog populations currently occur in Hluhluwe‐iMfolozi Park (HiP), Mkhuze Game Reserve (MGR) of Isimangaliso Wetland Park and Thanda Private Game Reserve (TPGR) all of which are bordered by a matrix of natural habitats and human settlements. Thus, land outside these protected areas could be utilized to expand wild dog distribution and provide connectivity between existing resident populations of wild dogs within KwaZulu‐Natal. To investigate the viability of such an approach, Maximum Entropy Modelling (Maxent) was used to characterize habitat niche selection of dispersing wild dogs, and to identify potential dispersal linkages between current wild dog metapopulation reserves. The model was calibrated using 132 location points collected from 2006 until 2009. From 2008 to 2009 I also conducted a survey of 247 community members in tribal authorities bordering HiP and MGR, to understand factors influencing attitudes towards wild dogs. A habitat suitability model with seven predictor variables had an AUC of 0.96 (SD = 0.02) and indicated four variables which best predicted probability of presence for dispersing wild dogs: elevation, road density, land cover and human density. The results suggest that elevation and land cover may be of greater influence for dispersing wild dogs than human density or activity. Elevation was the single most effective variable indicating a higher probability of presence for dispersing wild dogs in lower lying locations; peaking at approximately 200 – 300m a.s.l. Wild dogs also showed a preference for Woodland and Bushland habitats which in KwaZulu‐Natal tend to be found on lower lying topography. A preference for areas of lower human density and a highest probability of presence at road densities of approximately 0.7km/km2 or less would suggest that while wild dogs may show a tendency to avoid areas of high human activity, they can coexist in close proximity to humans. Respondent’s attitudes, knowledge of wild dogs and livestock husbandry were interpreted by the development of a set of indices. Attitudes were positively related to formal education levels and wild dog‐specific education, but were not influenced by demographic factors such as gender, age and employment status. Eighty three percent of respondents believed efforts to protect wild dogs should continue. Respondents with higher numbers of livestock tended to have more positive attitudes towards wild dogs despite generally incurring higher losses to carnivore depredation than those with less livestock. This appears to be because the financial burden of livestock losses to those with fewer livestock is perceived to be a loss of a greater proportion of total financial wealth. The study highlighted the substantial scope for improvement in livestock management. Theft (34 percent), drought (30 percent) and disease (14 percent) were ranked as the greatest problems facing livestock owners while predators were ranked as the greatest problem by only 4 percent of respondents. My findings suggest that wild dogs are generally viewed positively or with ambivalence. Concerns over the potentially increasing threat to livestock, as natural prey numbers outside protected areas decline and wild dogs disperse from natal packs, are likely to be manageable. However, wild dog population expansion within KwaZulu‐Natal will continue to rely on managed core populations on perimeter‐fenced metapopulation reserves with tolerant communities and landowners contributing to the connectivity of isolated reserves. Generation of tolerance can be instilled through continued advocacy and education, supported by conflict mitigation initiatives and rapid response to conflict reports. The implementation of incentive schemes for adjoining private landowners to co‐manage wild dog populations will need to be addressed in conjunction with managed metapopulation practices and law enforcement, to promote range expansion, and reduce potentially lethal edge effects and wild dog‐human conflict.
- Full Text:
- Date Issued: 2012
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