A dissertation submitted in fulfilment of the academic requirements for the degree of Masters of Environmental Science, School of Animal Plant and Environmental Sciences. University of the Witwatersrand. October 2016. / Fire and grazing are important drivers of grassland composition and function in savanna ecosystems. Fire alters the forage quality and vegetation structure, so changing fire regimes also changes grazer utilisation of the landscape. This study aimed to investigate how different fire regimes, specifically changes in fire size and season of burn, influence grazer attraction as well as grazing intensity and duration in the short-term, and further to determine how long-term fire-grazing interactions may influence the development of grazing lawns. In the short-term experiment, fires of three different sizes were applied in both the early dry season (EDS) and late dry season (LDS), and periodic collection of grass height and dung count data was conducted over a full year. Results showed that grazers were immediately attracted to the burned areas after the fires, and that fire and grazing together can maintain a short grazed patch for a full season. The greatest grazer visitation and grazing pressure (shortest grass) was observed on the intermediately sized burns (5ha). Furthermore, EDS treatments exhibited less initial grazer visitation but grass was kept in a short state for longer than on LDS burns. LDS burns had more intense grazing but over a much shorter time. For the long-term experiment, a long-standing fire experiment (Experimental Burn Plots, Kruger National Park, South Africa) was used to investigate change in grass community composition as influenced by firegrazing interactions over a 60 year period. Historical data were used, and grass composition data were also collected on three treatments that allowed for comparison of communities that experienced grazing and fires repeated at different fire frequencies and different seasons (April biennial and August annual burns), as well as a natural fire regime (control). By investigating the change in abundance in a few key grass species, grass ecological status classes, and grass functional guilds, results found that grasses associated with grazing lawns (stoloniferous, ‘disturbed’) increased in abundance, while grasses of bunch grass communities decreased, and that this change was more pronounced on April biennial burns. The results of this study show that small fires can act as a catalyst for grass community compositional and structural change by attracting grazers. Key words: Grazing lawns, fire size, fire season, pyric-herbivory, savanna. / TG2016

Thesis (MScAgric)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The aim of this study was to evaluate the current managerial practices as used by African Savanna buffalo (Syncerus caffer caffer) farmers. Consequently, the best management practices would be combined to formulate a basic management plan to farm captive buffalo. The distribution of buffalo throughout South Africa was also investigated and each province was considered separately for different types of buffalo (Kruger also known as project; Addo and other) and different disease statuses (Foot and Mouth; TB; Corridor disease and disease-free or clean). The basic infrastructure of all farms studied was noted and evaluated to attain the most effective structures and layouts needed for basic captive buffalo farming. The reproductive capabilities of buffalo were assessed on different farms. These farms were divided into winter and summer rainfall areas to ascertain whether season or rainfall would have an effect on calving season. Additionally the reproduction data was analysed to set a benchmark for the reproductive performance of buffalo in herds as well as individually. This assisted in selection in captive breeding of buffalo. Buffalo are currently distributed throughout South Africa and occur in all nine provinces, with the highest quantity found in Limpopo with 1300 registered buffalo farms. Provinces that contain only disease-free buffalo include Western Cape, Eastern Cape, Freestate, North-West and Gauteng. Corridor infected buffalo are found in the Northern Cape, Mpumalanga and KwaZulu Natal. Foot and Mouth disease is found in Limpopo and Mpumalanga and TB infected buffalo are found in Mpumalanga and KwaZulu Natal. Factors to consider when managing captive buffalo herds are the herd dynamics and composition, feeding and nutrition and lastly parasite control. Management should be approached adaptively as different areas present different challenges. Infrastructure is divided into the farm and biomes thereof, feeding and parasite treatment. As with herd management these should be approached adaptively as the composition of each farm differs. Reproductive maturity of buffalo is reached between the ages of two and six years. Average intercalving period of captive buffalo was to be 443 days with optimal intercalving being below 400 days. Seasonal calving differences between summer and winter rainfall areas were found with calving peaks differing by two months between these areas. / AFRIKAANSE OPSOMMING: Die doel van hierdie studie was om die bestuurstegnieke wat tans deur Afrika Savanna buffel (Syncerus caffer caffer) boere gebruik word te evalueer. Gevolglik sal die beste bestuurs praktyke gekombineer word om ‘n basiese bestuursplan the formuleer om omheinde buffels te boer. Die verspreiding van buffels in Suid-Afrika is ook ondersoek en elke provinsie is afsonderlik oorweeg vir die verskillende tipes buffels (Kruger ook bekend as projek; Addo en ander) en verskillende siektestatusse (Bek-en-Klou seer; TB; Corridor siekte en siekte-vrye of skoon). Die basiese infrastruktuur van al die plase in die studie is genoteer en geivalueer op die mees effektiewe strukture en uitlegte vas te stel wat benodig word vir die boer van omheinde buffels. Die reproduktiewe vaardighede van buffels is geassesseer op verskillende plase wat verdeel is in winter en somer reënval streke om vas te stel of seisoen of reënval ‘n invloed het op kalf seisoen. Die reproduksie data is ook geanaliseer om ‘n riglyn te stel vir die reprodutiewe prestasie van buffels in ‘n kudde asook individueel. Dit sal help met die seleksie van teel diere. Buffels is tans wyd versprei oor Suid-Afrika and kom in al nege provinsies voor met die hoogste hoeveelheid in Limpopo (1300 geregistreerde buffelplase). Die provinsies wat slegs siekte-vrye buffels bevat is Wes-Kaap; Oos-Kaap; Vrystaat; Noord-Wes en Gauteng. Corridor-besmette buffels kom voor in Noord-Kaap; Mpumalanga en KwaZulu Natal. Bek-en- Klou seer kom voor in Limpopo en Mpumalanga en TB kom voor in Mpumalanga en Kwa- Zulu Natal. Faktore wat oorweeg moet word met die bestuur van omheinde buffeltroppe is kudde dinamika en samestelling, voeding en laastens parasiet beheer. Buffelbestuur moet aanpasbaar wees aangesien verskillende areas verskillende uitdagings bied. Infrastruktuur kan opgedeel word in die plaas en sy biome, voeding en parasiet toediening. Soos met kudde bestuur moet infrastruktuur ook aanpasbaar wees, aangesien die samestelling van elke plaas verskil. Reproduktiewe volwassenheid van buffels word bereik tussen die ouderdomme van twee en ses jaar. Gemiddelde interkalf periode vir omheinde buffels was 443 dae met optimale interkalwing van minder as 400 dae. Seisoenale kalwingsverskille tussen somer en winter reënvalstreke is opgemerk met kalf pieke wat verskil met twee maande tussen die streke.

A study of habitat selection by large wild ungulates was carried out on a 50 cm2 area in the sub-tropical Lowveld region of eastern Transvaal province, South Africa. Estimations were made of herbaceous forage net productivity and ungulate secondary productivity on the same area. Fourteen vegetation types, varying in composition and structure from open savanna to dense woodland, were delineated by association analysis. Structural and vegetational characteristics which were considered to influence ungulate distribution were measured within each vegetation type. The study area supported resident populations of seven ungulate species during the wet season; drv season densities were higher due to population influxes from surrounding areas. Densities ranged from 13 to 67 animals per km2, with impala making up from 40 to 70 percent of the total population, wildebeest 10 to 40 percent, and lesser proportions of giraffe, zebra, kudu, warthog and waterbuck. Savanna vegetation types supported total densities of up to 185 animals/km2, while wooded types support fewer animals. Waterbuck were the most selective of the ungulates and concentrated mainly in the riparian woodland. Wildebeest, zebra and giraffe made variable use of savanna and open woodland types. Warthog preferred savanna types and avoided woodland. Impala were less selective, and kudu showed no habitat preferences. Ungulate distribution was related to several habitat characteristics, and the key factors were found to differ in each case. Each species had a unique combination of habitat characteristics to which it responded in linear fashion, and this was considered to be the way in which ungulates avoided competition by achieving spatial separation. Herbaceous forage standing crops and net production were functions of vegetation composition, soil types, rainfall and extent of ungulate utilization. Standing crops ranged from 350 to 4104 kgs/ha air-dried forage. Net primary production ranged from zero to 2719 kgs/ha; vegetation types on sandy soils did not produce in years with poor precipitation. Ungulates consumed about one-fourth of the herbaceous net primary production during the wet season and more than four-fifths during the course of a full year. Ungulate biomass on the area averaged about 40 kg/ha during the wet season and 65 kg/ha in the dry season, but biomasses varied a great deal with vegetation type, ungulate population species coMposition and seasonal densities. Ungulate secondary product ion varied correspondingly and ranged from 1.3 x 10-3 kcal/m2 per day to 4.8 x 10-3 kcals/m2 per day. Overall secondary production rate for the 2-year study period was 0.97 kcals/m2 per year, produced from a mean standing crop of 7.46 kcal/m2.

The Ethiopian Wildlife Conservation Organization has little information on the lll extent and ecological determinants of plant species composition and distribution in Omo National Park. Elsewhere, the determinants of African savanna vegetation dynamics have been the focus of numerous investigations, yet our understanding of the hierarchical nature and relative importance of any relationships remains very general. As well, our ability to derive predictions about vegetation responses is limited to extreme generalizations. African savanna landscape ecotones have received even less attention than most landscapes. In this dissertation, I test hypotheses about plant species distribution-determinant relationships in Omo National Park, a park that occurs in a landscape ecotone. Determinants investigated include rainfall and topographic-related gradients in soil moisture and edaphic conditions, and availability of soil constituents. Rainfall pattern was determined from meteorological data and multiple linear regression. Topographic attributes were measured in the field. Availability of soil constituents was determined by evaluating and using spatial interpolation models using limited soils data, and construction of surface soil maps. Hypotheses were tested using the simple and partial Mantel tests of matrix association. Results demonstrate that predictions using spatial interpolation models based on limited, coarse-scale soils data are accurate and reliable when compared with more data-intensive investigations. Results using spatial statistics indicate that the nature of the spatial pattern of perennial species associations is a monotonic spatial trend. The distribution of perennial species associations is influenced both directly or indirectly by rainfall. An indirect rainfall relationship occurs when there is variability in topography. The means of influence by the topographic-related attributes is unclear despite significant Mantel results. In the topographically invariant portion of the study area, however, exchangeable sodium and magnesium concentrations appear to indirectly influence the distribution of perennial species associations. Strength and ordering of the vegetation-determinant relationships varied depending on the type of perennial species association type being investigated. Differences in species range of tolerance and rate of change in species association, depending on association type, landforrn, and parent material differences, account for the nature of the vegetation-determinant relationships, the ordering of the determinants, and variability in responses.