Msinsi Holdings (Pty) Ltd are considering the introduction of nyala to Shongweni Dam and Game Reserve in KZN. This reserve has a naturally resident population of bushbuck and is located beyond the natural distribution of nyala. Concerns for competition between these two species causing declines in bushbuck numbers elsewhere prompted the present study. The main aim of the present study was to determine some aspects of the ecology of bushbuck within the reserve to assist with decision-making regarding the introduction of nyala and species specific-management of bushbuck at the study site. Bushbuck home range and habitat utilisation was investigated with the aid of radio telemetry and Geographical Information Systems. Estimates of total home range size for males using minimum convex polygons (MCPs) and fixed kernels (FKs) were 33.9 ha and 32.1 ha respectively. Estimates of total home range size for females using MCPs and FKs were 12.0 ha and 13.5 ha respectively. A significant difference between total home range size for gender (male and female) was found but there was no significant difference for age (adult and subadult). Bushbuck typically utilised one core area within their home ranges in which 50 % of their time was spent in approximately 17 % and 11.7 % of their total home range for males and females respectively. A substantial overlap in total home range and core areas between animals was found. Bushbuck showed preference for short thickets and avoidance of low closed grasslands. High reedbeds were utilised in proportion to their availability and tallwoodlands were not utilised by the study animals, but were observed to be utilised by other non radio-collared bushbuck. Habitat preference was a consequence of favourable cover being provided by the structure of the vegetation and the occurrence of favourable foraging species. Bushbuck utilisation of topographical aspect was largely determined by the vegetation type that occurred on the respective slopes. Estimations of bushbuck density and abundance were made using sighting efforts, drive counts, and mark-resightings. Sighting efforts using distance sampling during spring were found to be the most effective in terms of accuracy and man-hour costs, however, these were still not considered to be precise estimations of the total bushbuck population at SDGR, but would be useful for monitoring population trends as a result of the high repeatability and simplicity of the method. Sex, age ratios and nocturnal activity were determined using field classification. The field classification method of age and sex ratio determination used during the present study was found to be very subjective and was therefore suggested to have produced ratios which may be largely biased towards the female component of the population. This in turn also effected the determination of social organization and was evident when compared to previous studies. Bushbuck activity determined from radio telemetry and sighting efforts produced results that corresponded with all previous studies, showing bushbuck to be largely nocturnal, moving much larger distances at night than during the day, and spending most of their time walking and feeding at night. The status and management of synoptic bushbuck and nyala in KwaZulu-Natal was also investigated by means of a questionnaire survey. From the opinions of landowners and reserve managers, the status of bushbuck sharing a sympatric relationship with nyala in KwaZulu-Natal (KZN) appeared to be stable to declining, whereas nyala status was increasing. This trend was suggested to be a result of competition for resources between the two species. Northern KZN recorded a higher frequency of this trend (57.7%, n = 26) compared to the Midlands (35.7%, n = 14), as did Ezemvelo KZN Wildlife Reserves (85.7%, n = 7) compared to privately owned properties (42.4%, n = 33). Very little species-specific management for nyala and bushbuck occurred in reserves that participated in the present survey. / Thesis (M.Sc.)-University of KwaZulu- Natal, Pietermaritzburg, 2003.

No abstract available. / Thesis (M.Env.Dev.)-University of Natal, Pietermaritzburg, 2003.

Browse selection, intake, utilisation, palatability, quality and production are tightly linked and need to be considered together in trying to improve our understanding of browsing dynamics and the interactions between browsers and vegetation. Such an understanding is necessary in order to re-evaluate determinations of browser carrying capacities and evaluating actual and potential impacts of browsing animals on vegetation composition and diversity. Browser carrying capacity is determined by both the quantity and the nutritive value of forage. The measurement of browse quantity and nutritive value and the matching of browse supply to browser demand are central to sustainable utilisation and the monitoring of vegetation health. South African savannas are poorly studied with respect to tree canopy growth and browse production making it difficult to quantify the available browse biomass on which browsing capacity estimations are based, and consequently difficult to estimate levels of browsing that are sustainable. This study addressed these issues by investigating browse dynamics, broadly aiming to (1) explore factors affecting browse production, biomass and nutritive value; (2) develop models to assess and monitor these parameters across seasons and properties; (3) use the resultant models in improving our understanding of how to determine browser carrying capacities. More specifically, our study sought to examine the effects of plant physiognomy, forage nutritive value, canopy stratum, defoliation, temperature, rainfall and soil nutrient status on the browse production of evergreen (Carissa bispinosa, Euclea divinorum, Gymnosporia senegalensis), semi-deciduous (Spirostachys africana, Ziziphus mucronata) and deciduous (Acacia nilotica, Dichrostachys cinerea) savanna tree species from June 2003 – June 2005 in three sites along the northern Zululand coastline of KwaZulu-Natal. Available browse biomass, during the dry season, of four key savanna tree species (A. nilotica, E. divinorum, G. senegalensis, and S. africana) was estimated through the development of allometric regression equations. Non-linear regression was used to investigate the relation between the leaf dry mass (LDM) and canopy volume (CVol) of each of the four tree species. Exponential regression (y = a + brlnx) of the natural logarithm of CVol data provided the most accurate and precise description of the tree CVol – LDM relation. A study was undertaken to determine which factors may influence browse production in a southern African savanna. Regression tree models for the browse production identified that the dominant factors influencing browse production were CVol (m3), season, species and height to the lowest leaves of the tree canopy (HL) (m). The length of the growing season had a marked effect on the production potential of savanna tree species, suggesting that improved conditions for growth, i.e. greater rainfall, soil moisture content and improved soil nutrient availability result in a longer period of rapid sustained growth. Species was identified as an important contributing factor to differences in browse production rates, suggesting the need for the development of species or species group models. Mean annual browse production of evergreen trees was greater than that of deciduous and semi-deciduous trees. Mean quarterly (three monthly) browse production was highest, for all trees, during the wet season, with the greatest difference between wet and dry season production being observed in deciduous forms. Evergreen forms showed continuous growth over the whole study, with enhanced growth over the wet season. Deciduous forms, on the other hand, concentrated growth in spurts, when environmental conditions became favourable, with most production occurring during a short growing season. Browse nutritive value was found to be greatest during the wet season, when growth and photosynthesis are at their greatest. Further, browse nutritive value was greatest in deciduous species. Evergreen trees were found to have greater acid detergent fibre (ADF) concentrations than both the deciduous and semi-deciduous trees. By contrast, crude protein (CP) concentrations were greater in semi-deciduous and deciduous species than in evergreen species. The daily CP requirements for maintenance for an adult impala (45 kg) were met by all species over all three study areas and all seasons. Daily CP requirements for growth and lactation, however, were only ever met by deciduous and semi-deciduous species, though this result was not consistent over study areas and seasons. Predictive models for the production of browse on deciduous, semi-deciduous and evergreen trees in northern Zululand were developed using multivariate adaptive regression spline functions. The best predictors of growing season browse production in all three tree guilds (defined here as a group of trees having a characteristic mode of living) were primarily measurable tree dimensions, while the prevailing environmental conditions had little impact. Differences in the production, nutritive value and available browse biomass between the different tree forms and seasons have a profound effect on the determination of browser carrying capacities and need to be incorporated into any game or conservation management plan. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

KwaZulu-Natal’s Hluhluwe-Imfolozi Park has historically been prioritized for biodiversity conservation but it also has the oldest protected wilderness area in the country. For 50 years, conservation management, tourism and education within the Imfolozi Wilderness Area have generally been carried out using non-mechanized wilderness principles. The validity of the Imfolozi Wilderness is constantly questioned in terms of efficiency, equity and aesthetics and is consequently subject to a variety of pressures that those different ideologies can exert. The historical development and applicability of the wilderness concept is examined here against evolving South African social and environmental circumstances. Whilst this investigation confirms the findings that colonialism and apartheid resulted in the exclusion of local peoples from protected areas, it also takes note that Imfolozi’s history is characterized by organizations and individuals who ignored the racist laws of the time. Nevertheless, management structures pertaining to both politics and conservation tended to be top-down, such that the Imfolozi Wilderness retained an air of elitism, regardless of attempts to be racially inclusive. Modern trends in protected area management expose the necessity of refining the justification of wilderness areas, to simultaneously recognize localized priorities and the importance of such areas to the planet’s ecological wellbeing. Without attempting to resolve philosophical debates but, at the same time, recognizing their validity, protected area management requirements for the Imfolozi Wilderness are examined in terms of the legal mandate handed to the management agency. This leads to the selection of the Limits of Acceptable Change planning and management system which is implemented as an action research project in conjunction with the Imfolozi Management Team, over a three year period. This involved: defining legal mandates and area issues; defining the zonation categories for the wilderness area; selecting the indicators to measure human impact; compiling an inventory of conditions in the wilderness area; specifying standards; examining alternative zonation category allocations from stakeholders and selecting a preferred alternative. The desired outcome was the establishment of a system in which managers could receive ongoing collaboration from stakeholders and consultatively develop a defendable wilderness management strategy that would meet the legal requirements of the area’s proclamation. Through a descriptive narrative, this dissertation provides an account of the implementation process and discusses to what extent this has been achieved. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.