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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Genetic verification of multiple paternity in two free-ranging isolated populations of African wild dogs (Lycaon pictus)

Moueix, Charlotte Henriette Marie. January 2006 (has links)
Thesis (MSc (Production Animal Studies))--University of Pretoria, 2006. / Includes bibliographical references.
2

Multi-host pathogens and carnivore management in southern Africa

Alexander, KA, McNutt, JW, Briggs, MB, Standers, PE, Funston, P, Hemston, G, Keet, D, Van Vuuren, M 25 November 2008 (has links)
Abstract A retrospective serosurvey of multi-host feline and canine viruses among carnivore species in southern Africa (n = 1018) identified widespread pathogen exposure even in remote protected areas. In contrast to morality experienced in East African predators, canine distemper virus (CDV) infection among African wild dogs (Lycaon pictus) in Botswana was not associated with identifiable change in pup survivorship or disease related mortality of adults. A disease outbreak of unknown aetiology occurred in the same population over 4 weeks in 1996. Outbreak boundaries coincided with ecotones, not the spatial distribution of contiguous packs, highlighting the potential importance of landscape heterogeneities in these processes. Direct management of pathogens in domestic animal reservoirs is complicated by the apparent complexity of pathogen maintenance and transmission in these large systems. Conservation effort should be focused at securing large metapopulations able to compensate for expected episodic generalist pathogen invasion and attention directed to addressing underlying causes of population depression such as habitat loss and wildlife conflict.
3

The effects of two formulations of deslorelin on the reproduction of male African wild dogs (Lycaon pictus)

Newell-Fugate, Annie E. January 2008 (has links)
Thesis (MSc (Production Animal Studies))--University of Pretoria, 2008. / Includes bibliographical references. Also available in print format.
4

Feeding ecology and carrying capacity of a reintroduced pack of African wild dogs in a relatively small, fenced reserve.

Niemann, Sophie Mary. January 2010 (has links)
Reintroduction has been used successfully as a tool to restore declining populations of many threatened species. However, the lack of detailed evaluations of past reintroduction attempts has hindered a priori planning of management actions to achieve conservation goals. The metapopulation approach resulted in the most extensive and successful reintroduction efforts of the African wild dog (Lycaon pictus) in South Africa, but the approach was only recently evaluated by Gusset et al. (2008). For future reintroduction attempts to be successful on relatively small reserves, extensive evaluations are needed. Particular focus on feeding behaviour and impact on prey populations is essential to predict sustainability and carrying capacities in these areas for the African wild dog. A small reintroduced population of African wild dogs (pack number varying from 3 to 13 during the study period) were studied in the Karongwe Game reserve (79 km2) between January 2002 and January 2004. Fourteen prey species were identified: impala (Aepyceros melampus, 60 %) was the most dominant prey followed in descending order by bushbuck (Tragelaphus scriptus, 7.4 %), waterbuck (Kobus ellipsiprymnus, 4.9 %), warthog (Phacochoerus aethiopicus, 4.7 %), kudu (Tragelaphus strepsiceros, 4.4 %), and grey duiker (Sylvicapra grimmia, 4.4 %). Generally, prey were included in the diet in relation to abundance, and the dogs were not rate maximizing foragers but, unlike the findings of previous studies, were opportunistic feeders. The fences and angles in the fence, were used to assist hunting, but only for medium sized prey, impala and bushbuck, which were killed significantly more than expected along the fence line. A predictive prey preference model was then tested, but the model did not account for possible differences in feeding behaviours and prey preferences found in this, nor another study from the small Shambala Game Reserve. The model had limited accuracy as a predictive tool for proposed reintroductions into relatively small reserves. Models which can predict carrying capacity and minimum area requirements were also tested. Large variation and low numbers were predicted, which conflicted with social requirements needed for the survival of the population; further the models did not account for interspecific competition nor simultaneous depletion of prey by other guild predator. If the metapopulation approach is to continue to be successful and sustainable, more detailed evaluations of reintroductions of African wild dog on relatively small, fenced reserves are needed to determine the impact of these dogs on prey populations, and to determine if African wild dog feeding behaviour does differ for these areas in comparison to previously described open systems. With this information, more appropriate protocols regarding reintroduction and management can then be developed, thereby meeting one goal of management and conservation for the African wild dogs and their coexisting prey populations, and which can be used as a model for managing other large predators. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2010.
5

The dispersal of African wild dogs (Lycaon Pictus) from protected areas in the Northern KwaZulu‐Natal Province, South Africa.

Whittington‐Jones, Brendan Mark January 2012 (has links)
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.
6

The ecology and conservation biology of the endangered African wild dog (Lycaon pictus) in the Lower Zambezi, Zambia

Leigh, Kellie A January 2006 (has links)
Doctor of Philosophy / The African wild dog (Lycaon pictus) is one of Africa’s most endangered carnivores. Previous research into this species has focussed on the largest extant populations in Africa. However, there are a large number of relatively small populations (20 to 50 dogs) distributed across Africa, which represent an important component of the diversity of the species and its remaining habitat. This study investigated the status of a small population of wild dogs in the Lower Zambezi area in Zambia. Objectives focussed on assessing population dynamics and identifying causes of decline. Research was carried out over a broad range of topics in an effort to provide comprehensive information for conservation management of the population. The scope of the project was divided into five sections: 1) Demography and pack dynamics were assessed to identify the structure and status of the population, and the main causes of mortality. 2) An assessment of habitat types and related ecological factors was carried out to determine wild dog habitat utilisation in relation to vegetation type, prey densities and hunting success in each area. 3) The effects of interpredator competition on wild dog population dynamics was investigated, specifically, the effects of lions (Panthera leo) and spotted hyaenas (Crocuta crocuta). 4) Genetic analyses were carried out to assess the historic and contemporary genetic variability of the population, and to define patterns of geographic structuring and population differentiation. 5) Results were combined to assess the viability of the population and recommend conservation management strategies. Snaring was identified as the most important cause of adult mortality, and a threat to wild dog population persistence. Inbreeding avoidance led to the emigration of adult males and females from the area and appeared to be a substantial contributor to population decline. Limited mate selection corresponded with neither sex displaying philopatry and large dispersal distances effectively removed adults from the population. This result has important implications for the management of small populations, whereby lack of mate choice may increase dispersal distances and thereby increase edge effects on populations, regardless of home range sizes. Home range sizes were related to den locations in remote areas of the Zambian Escarpment, which was used as a breeding refuge area. The Zambezi River and Zambian Escarpment appeared to be effective barriers to wild dog home range movements. The study area contained a diversity of habitats on the alluvial terraces of the river valley floor. There was a high density of impala (Aeypceros melampus), which formed the main prey base for the wild dog population. Studies of other populations have found that wild dogs often avoided areas with high competing predator densities, which corresponded with high prey density areas. In contrast to those findings, the Lower Zambezi wild dog population showed a strong preference for high prey density areas. This population also showed only temporal avoidance of high lion density areas. Low lion density areas were preferred during breeding periods, while moderate to high lion density areas were preferred during non-breeding periods. Direct predation of adult wild dogs by lion and spotted hyaenas was rare. Kleptoparasitism of wild dog kills by either competing predator species was also rare. Predator competition was not considered to be an important determinant of population decline. The Lower Zambezi population suffered from a loss of heterozygosity, low allelic richness, and there was significant evidence of a recent population bottleneck. The population did not contain any new mtDNA haplotypes, nor any unique alleles on the commonly used microsatellite loci, but was differentiated from African wild dog populations in other regions. There was evidence of historical and recent gene flow between the Lower Zambezi and the neighbouring southern African populations of Hwange and Okavango. This was the first study to show a loss of genetic variability in a free-ranging African wild dog population. Although more immediate anthropogenic and demographic factors were the critical determinants of population decline, the loss of genetic variability has important implications for the conservation of the remaining small and fragmented wild dog populations in Africa. Results showed that due to its small size the population is likely to have suffered from inverse density dependence and Allee effects on dispersal and reproductive success. Management recommendations focussed on mitigating anthropogenic causes of mortality, and improving connectivity with a larger, potential source population to increase the probability of successful dispersal and to restore genetic diversity. The high density prey base, small home range sizes and low levels of interpredator competition detected in this study suggest that the area has the capacity to support a large and potentially viable population of wild dogs if appropriate management strategies are implemented.
7

African wild dog (Lycaon pictus) area utilization in the northern Tuli game reserve, Botswana.

Van Wyk, Dewald. January 2013 (has links)
M. Tech. Nature Conservation / The influence of predation on ungulates is most commonly measured through the direct lethal effects of predators. However, indirect effects of predation risk may alter prey behaviour and survival. The introduction of a pack of African wild dogs (Lycaon pictus) into the Northern Tuli Game Reserve, Botswana, allowed various indirect responses of ungulates to predation risk to be investigated. The study focused on predation pressure and its effects on ungulate activities during the denning period of the wild dogs, and on how the distribution and density of prey and lions influenced wild dog movement patterns in both the denning and non-denning period.
8

The spatial ecology of lion (Panthera leo) and spotted hyaena (Crocuta crocuta) in Hluhluwe-iMfolozi Park : implications for the African wild dog (Lycaon pictus.

Graf, Jan Andreas. January 2008 (has links)
The ecological role of apex predators in ecosystems is increasingly recognized not only as a result of their affects on prey species, but also on the numbers and behaviour of other predator species within their guilds. In an African context, dominant apex predators such as lions (Panthera leo) and spotted hyaenas (Crocuta crocuta) have been implicated in limiting endangered intraguild species such as wild dogs (Lycaon pictus) via direct intraguild interactions, such as interference and predation. As a result of this it has been predicted that spatial and temporal refugia are critical for wild dogs to co-exist with lions and spotted hyaenas. Whether such refugia are actually present within small protected areas, such as Hluhluwe iMfolozi Park (HiP), within which these three species co-exist, has been questioned. For wild dogs, interference or predation refugia may be equated to areas or periods which contain a relatively low level of encounter probability with spotted hyaenas and lions respectively. By combining well established field research techniques, such as radio telemetry and audio playbacks, with novel geographic information system tools, I investigated the two key drivers of the probability of encounter with spotted hyaenas and lions, namely density and utilization intensity. Results from the analyses showed that substantial spatial and temporal variation existed in the utilization intensity of lions, as well as the density of both lions and spotted hyaenas, at short and intermediate time scales, in HiP. The spatial scale across which these patterns resolved appear to be well suited to the movement capabilities of wild dogs. This indicated that wild dogs may be able to exploit such areas of temporary lower density and/or utilization intensity, suggesting the dynamic nature of refugia involved in the interactions within these two species-pairs. Results from the lion analyses further suggest that groups rather than individuals are the basic units around which intraguild interactions of social predator and prey species should be investigated, and that social grouping in combination with predator territoriality may stabilize intraguild interactions. An important prediction emerging from this work is that wild dogs, or other subordinate African large predator species, may be forced to trade-off safety from hyaena interference vs. safety from lion predation. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2009. / National Research Foundation, The Green Trust (WWF–SA), The Wildlands Conservation Trust, University of KwaZulu-Natal, The Endangered Wildlife Trust, Smithsonian Institution, Sichel Family Endowment, Friends of the National Zoo, THRIP, Wild about Cats, Hluhluwe Tourism Association, Bateleurs, Third World Academy of Science, The Wild Dog Foundation, and The Sally Club.
9

The effects of captivity on display-based communication and social interaction in the captive African wild dog (Lycaon pictus)

Tighe, Emily Jayne January 2013 (has links)
The obligate cooperative nature of African wild dogs (Lycaon pictus), unique among social canids, is thought to be driven by high levels of interspecific competition and intra-guild predation with other large socially-organised predators. Research exploring how wild dogs maintain social bonds through social communication, while avoiding detection from potential competitors, is therefore vital for understanding this species. While olfactory and vocal communications are well represented in the literature concerning L. pictus, these channels of communication pose significant risks to wild dog survival, as they are inherently susceptible to eavesdropping by unintended receivers. In comparison, display communication, which requires visual contact between the signaller and receiver, poses comparatively less risk of attracting the attention of eavesdroppers. In spite of this, few studies have explored the use of display communication in wild dogs, leaving its potential significance in maintaining social bonds within packs unexplored. Using video analysis, I investigate how display communication and subsequent social interaction are affected by several pressures of the captive environment. Captivity did not appear to affect the presence of many social display types also used by free-ranging wild dogs. However, sexual behaviour was absent from the study groups, likely due to the use of contraception and pack sex composition. The effects of pack sex composition (single-sex versus mixed-sex) revealed that while the frequencies and durations of many social behaviours were not affected by sex composition, the distribution of social interactions did differ depending on group structure. Here, a highly related, single-sex group was more stable than a highly related, mixed-sex group of the same size. Differences in the captive management strategies, specifically enclosure size and feeding regime, of the two packs, may explain the behavioural differences observed. The death of a pack member permitted investigation of the effects of death on social interactions. While many of the social interactions were unaffected by the death, behaviours relating to the formation and maintenance of social dominance and social hierarchy increased after the dog’s death. The distribution of social interactions was non-random, suggesting that individuals were reorganising the social structure of the pack during this period. Finally, a small study into the effects of simultaneously added enrichments in the pack (post death) revealed that enrichment reduced the frequencies of dominance behaviours and allowed for a more even distribution of social interaction within the pack. This demonstrates how enrichment may potentially be used to reduce aggression within captive animals. Overall, this research reveals that display-based communication is important for the maintenance of sociality in captive African wild dogs. To better understand this endangered species, future studies in free-ranging populations should include this channel of communication.
10

The physiological and biomechanical assessment of free ranging sports dogs

Wills, Alison P. January 2013 (has links)
No description available.

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