Thesis (M.Sc.(Wildlife Management)--University of Pretoria, 2000. / Summary in Afrikaans. Includes bibliographical references.

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A Thesis Submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in Fulfillment of the Requirements for the Degree of Doctor of Philosophy. October, 1995. / The methods of vicariance biogeography are in general rendered equivocal by widespread taxa. Standard methods resort to ad hoc assumptions in their treatment of widespread cases, and the results are always si bordinate to the addition of new data on endemic sister taxa. I introduce an alternative method for the analysis of widespread taxa based on the vicariance model. The method requires first the development of a habitat model for each species included in the analysis. I analyse the actual and "potential" distributions by cladistic methods, employing a weighting system designed to factor out the influence of ecological similarity. The resolution of the inferred area relationships is seen to increases with the application of the weighting-compelling evidence that the pattern reflects historical relationship. I review current approaches to the modelling of habitats. All seem to be based on an ecological model of equilibrium, where the limits of actual species distributions are thought to reflect habitat, as if historical contingency played no significant part in determining the shape of real distributions. Under this model all approaches are group discrimination methods. I reject these methods and develop a new method based on principal component analysis. I analyse the distributions of all extant endemic African antelope and derive probability surfaces for each species. The model output can be interpreted as species distribution free oflHstory-its potential distribution. This is different from assuming that actual distributions are free of history. Areas oferdemism are seen to be historical entities, not simply distributional ones, and the resulting area cladograrn is interpreted as the hierarchical pattern of endemism. A striking feature of the inferred pattern of endemism is the intersection of an east-west equatorial biota, and a north-south savanna biota. These bisect in East Africa at the centre of highest antelope diversity. I predict that this feature will be seen to be the most persistent feature of endemic structuring in other African taxa with high East African diversity. / AC2017

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg in fulfillment of the requirements for the degree of Masters in Science. Johannesburg, August 2016. / Resource selection by herbivores is driven by processes operating across a multitude of spatial scales and is influenced by a variety of biotic and abiotic environmental conditions and resources across the landscape. Spatial scales levels are crucial in habitat selection studies because they affect the interpretation of results and what may appear important at one level may not be relevant at another. Decisions made by animals at these levels can influence animal movements and hence the spatial distribution of populations. In this way, the use of resources across different scales by individual and groups of animals can be linked to population performance as a whole. Within home ranges, habitat use is mostly influenced by variation of food resources and water availability together with competition and predation risk. The study aimed to determine sable home range extent and habitat use and to test how predation, competition and other environmental factors influenced the selection of areas within these home ranges, in the thriving sable population of the Gorongosa National Park (GNP), Mozambique. Two adult females, one per herd, were fitted with GPS collar providing 5 hours interval GPS coordinates over a year, which were used to determine the annual and seasonal home ranges extents. Home ranges were then overlaid with vegetation map to analyse habitat use. Contrary to expectation, sable home ranges in this study were larger than those found in previous studies. The herds did not limit their habitat use to woodlands, using also open grasslands, drainage lines and bottomlands that retained green grasses during the dry season. Both herds expanded their ranges during the dry season, searching for those areas that still retained green grasses and searching for remaining water sources. For the resources selection within home ranges, I used the same GPS collar coordinates to fit seasonal logistic regression models with biotic factors (predation risk and competition) and with environmental variables (distance from water, distance from roads, elevation, slope, NDVI, vegetation types and landscape). Results show that sable were less prevalent in areas with high predation risk, but herds differed in prevalence with competitors, one herd favouring areas with high reedbuck concentrations and the other favouring low concentrations. Effects of environmental variables were different between seasons and between herds, being distance from water, distance from roads, greenness and elevation the most influential environmental. Both herds, however, avoided low elevation areas during the wet season, probably in order to avoid areas flooded during this period. As conclusion, predation risk and competition influenced selection within home ranges by sable in the GNP, despite low densities of potential competitors and lions. Nevertheless, this influence seems to not be enough yet to limit the success of the population. The herds also showed evidences of being affected by dry season, as demonstrated by the home ranges expansions during this period. With increase of herbivores population other that sable, and consequently increase competition and decrease of availability of resources, this could lead to reduction of growths percentages of the sable population in the park in the future. / MT2018

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Blood was collected from 71 tsessebe antelope and ticks from 12 of these animals, in the Vaalbos National Park. The samples were collected when the animals were relocated to a new park as a result of the deproclamation of Vaalbos National Park. DNA was extracted from the blood samples and the V4 hypervariable region of the 18S rRNA gene of any piroplasm parasites present was amplified by PCR. The RLB hybridisation technique was used to identify piroplasm parasites. Theileria spp. were identified and full-length 18S rRNA genes were amplified, cloned and sequenced. The results indicated the presence of novel Theileria spp. phylogenetically very closely related to both Theileria sp. (sable) and Theileria separate. The ticks collected were all Rhipicephalus evertsi evertsi, which has been shown to be capable of acting as a vector for Theileria spp. All animals appeared to be in good health at the time of sampling and after relocation. It is thus possible that, as with several other wildlife species, the Theileria spp. identified here do not cause disease under normal circumstances and that a situation of endemic stability exists. Once the host is under any form of stress, however, overt clinical disease may well become evident. The significance of these Theileria spp. should not be underestimated, and care should be taken not to transmit the organisms into new areas. More research will need to be conducted to determine the exact clinical significance of these findings and the role of Rhipicephalus evertsi evertsi as a potential vector for these Theileria spp. Copyright / Dissertation (MSc)--University of Pretoria, 2008. / Veterinary Tropical Diseases / unrestricted

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