MSc., Faculty of Science, University of the Witwatersrand, 2011 / ABSTRACT Observations of the changes in woody plant density in the Kruger National Park (KNP) over 58 years have shown an increase in large woody plant density on granite substrates, which is attributed to fire and herbivore density. Woody plants persist in areas with frequent fires, herbivory and drought by resprouting or protecting seeds in the ground. Soil seed banks, which are stores of seeds below ground or in leaf litter, provide 'insurance' for trees and allow populations to persist in unfavourable environments. No comprehensive studies have been conducted on soil seed bank ecology of Acacia species in the Kruger National Park, a research gap which this study aimed to fill. The spatial distribution and density of in situ soil seed banks for four Acacia species, A. grandicornuta, A. nilotica, A. senegal and A. tortilis was assessed in the Skukuza land system of the KNP, South Africa. In situ soil seed banks were quantified for eight mature trees per species during 2005/2006. Greenhouse and field seed burial trials were carried out for one year and 16 months respectively, between 2005 and 2007, to investigate the persistence of Acacia seeds over an extended period of time. Post-dispersal seed predation of Acacia seeds was investigated during July 2006 in six demarcated grids within 15 km of Skukuza. Overall soil seed bank density differed significantly among species, being highest for A. tortilis (19.5 ± 6.4 seeds m-2), followed by A. grandicornuta (12.1 ± 6.9 seeds m-2), A. nilotica (4.9 ±1.8 seeds m-2) and lowest for A. senegal (0.6 seeds ± 0.4 seeds m-2). Generally, seed bank density decreased with depth in the soil and distance from the centre of the tree canopy. Seed bank density increased significantly with a decrease in soil compaction for A. senegal only, while it was not related to over-storey canopy shading or herbaceous biomass for any of the species. No significant relationship was found between seed bank density and tree characteristics such as stem diameter, bark thickness or tree canopy area for any of the species. Viability of seeds from the seed bank decreased between species as follows: A. tortilis (77% of 142 seeds), A. nilotica (61% of 39 seeds), A. grandicornuta (58% of 87 seeds), and A. senegal (0% of 4 seeds). For all species with viable seeds, viability decreased with distance from the centre of the tree canopy. Bruchid beetle predation (assessed on 100 newly produced seeds) was low for all four species. Fifty seeds each of A. grandicornuta, A. senegal and A. tortilis and 100 A. nilotica seeds were destroyed by fire during the field seed burial trial, of which four hundred seeds/species were used. Of the remaining seeds, 15% of A. senegal, 19% of A. grandicornuta, 34% of A. nilotica and 66% of A. tortilis remained intact after 16 months in the field. Of these, 65% of A. tortilis, 27% of A. nilotica, 5% of A. grandicornuta and no A. senegal seeds were still viable. The percentage of remaining intact, viable seeds was highest under tree canopy cover and buried for A. tortilis (86%), A. nilotica (39%) and A. grandicornuta (6%), but the micro-site placement of seeds had a significant effect on viability for A. nilotica only (d.f. = l; χ2 = 7.5; P = 0.006). In the greenhouse seed burial trial (150 seeds/species/treatment), one percent of the total seed lot germinated, which was 2.9% of A. grandicornuta, 0.7% of A. senegal and 0.2% of both A. nilotica and A. tortilis. A. tortilis had the highest percentage of remaining intact, viable seeds (92.2%), followed by A. nilotica (58.3%), A. grandicornuta (57.6%) and A. senegal (0%). The number of remaining intact, viable seeds was highest when watered with the average rainfall (327 seeds), followed by the highest (314 seeds) and lowest rainfall (296 seeds). There was no association between rainfall treatments and the number of remaining intact, viable seeds for any of the species, except for A. grandicornuta where the number of remaining intact, viable seeds increased significantly with the average rainfall. Across six grids in the Skukuza land system, A. grandicornuta was the most dominant woody plant of six study species, followed by Dichrostachys cinerea, A. tortilis, A. nilotica, A. senegal and A. nigrescens. Woody plant density in grids varied between 226 plants ha-1 (Grid 3) to 1618 plants ha-1 (Grid 5), with a mean density of 862 ± 195 plants ha-1. Overall, woody plant species diversity was low (Shannon Wiener Index, 1.8 ± 2.8; Evenness Index, 0.7 ± 0.02; Simpson's Reciprocal Index, 4.5 ± 0.6). The dung of nine species of large herbivore was recorded across all six grids. Large herbivores favoured seeds of indehiscent (55 A. tortilis seeds and 11 A. nilotica seeds) over dehiscent pods (1 A. grandicornuta seed). Only 9% (five A. tortilis seeds and one A. grandicornuta seed) of the 67 seeds extracted from dung germinated after a six-week germination trial. Less than half the remaining ungerminated A. nilotica seeds (46%) and A. tortilis seeds (40%) tested viable. There was no correlation between the number of termitaria recorded and the number of Acacia trees growing on them (r = 0.07). Termite mounds occupied 0.0009 ± 0.0003 ha per grid matrix (0.8%). Only four rodent species were recorded across all six grids, Mastomys coucha (multimammate mouse), Rhabdomys pumilio (striped mouse), Aethomys chrysophilus (red veld rat) and Tatera leucogaster (highveld gerbil). Rodent species diversity was low (Shannon Wiener Index, 0.6 ± 0.2; Evenness Index, 0.6 ± 0.2; Simpson's Reciprocal Index, 1.9 ± 0.3). In the field cafeteria trial there was a significant difference in the percentage of seeds removed between seed species (P < 0.05; F = 2.8; d.f. = 3, 236). There was a significant difference in the percentage of seeds removed from trays placed under vegetation cover compared with trays placed in the open (P = 0.034). This study suggests that A. grandicornuta, A. nilotica and A. tortilis seeds form short-term persistent seed banks, while A. senegal seeds are transient and do not form seed banks. Seeds of several woody plants were ingested by large herbivores and selected by rodents. The relevance of soil seed banks to regeneration of Acacia trees needs to be evaluated by investigating whether these species rely more on seed production or resprouting for individual recruitment into tree populations. Once this issue is clarified the effect of certain factors on seed fate and consequently, recruitment of individuals into plant populations, can be more clearly understood. This will assist in managing and understanding these potentially encroaching species in the Kruger National Park, South Africa.

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, August 2016 / Monitoring the status and abundance of mammals, as well as establishing threats to biodiversity in different areas, is an essential management requirement in protected areas. Monitoring mammal species can assist in determining species interactions, patterns of behaviour and is important for further research, policy and management strategies. Water provision has implications for the preservation of wildlife, and is thus a management concern. Numerous studies monitoring mammal water utilisation patterns have employed traditional data collection methods, which are restricted primarily to diurnal observation during specific time intervals. Given the projected future impacts of global climate change on regional water availability, it is essential to investigate current water usage by mammals in the Kruger National Park (KNP), so as to better ascertain likely future water requirements under climate change scenarios. The use of remote photography for scientific observation, investigation and monitoring has many potential benefits, and an innovative and relatively new method through which one can observe mammal water source visitation patterns, is through the use webcams. There has been comparatively little research on mammal water requirements and visitation patterns at water provisioning sites using remote photography as a data collection method. Further to this, there is a gap in our knowledge concerning how daily climate variables (viz. temperature and rainfall) and astronomical conditions control water source visitation patterns at the finer temporal scale. This research primarily contributes to understanding contemporary water source visitation patterns and how this will influence future management decisions. At a broader scale, determining recent visitation patterns is critical in the context of projected future climatic changes and the associated water requirements for mammals of KNP. Webcam images were obtained for the period March 2012 - March 2014, captured at two artificial water sources in the central KNP. A clear divide is exhibited between herbivore and carnivore visitation patterns, with herbivores exhibiting exclusively diurnal patterns and carnivores’ nocturnal patterns. Significant relationships with Tavg intervals demonstrate that the majority of herbivores are shifting their visitation periods earlier in the day per 5°C increase in mean daily temperature, while the majority of carnivores are shifting their visitation periods later in the night per 5°C increase in mean daily temperature, however there is variability of species responses across the two study sites. Under the highest Tavg interval (30°C - 35°C) impala, warthog, southern giraffe, African buffalo and plains zebra exhibit a shift to earlier visitation by 1 – 6 hours, forcing them to utilise the water sources outside of their preferred temporal range. The influence of the timing of rainfall events indicates that the mean number of individual species sightings is significantly larger on days before rainfall compared to days after rainfall. The study highlights that waterdependent herbivores utilise the artificial water sources in relative proportion to their abundance in the central KNP, while water-independent herbivores are avoiding these artificial water sources. The findings of this research could be used to supplement current water provisioning guidelines and plan for water provisioning efforts in future. / TG2016

MSc., Faculty of Science, University of the Witwatersrand, 2011 / Abundance counts of ungulate species which are carried out using an aerial census are susceptible to measurement errors. These measurement errors result from environmental factors such as vegetation cover and the resultant effect that factors, such as the annual rainfall pattern, have on the accuracy of the count. Given these measurement errors, models of population abundance that are based on these counts should not only account for the population dynamic process - they need to model the measurement error process simultaneously in order to produce plausible estimates. In addition to this, the recorded counts from these censuses do not give a breakdown of the total count into the different gender and life-history stages of the animals counted. This research report investigates the usefulness of a hierarchical Bayesian hidden process modelling approach at explicitly including the measurement error process and a sub-model for the gender and life-history stage of the animals counted into a population dynamics model based on the aerial census counts. The data used are aerial counts of Kudu in the Kruger National Park from 1983 to 1993. The result is a model which estimates the measurement error in each year of the census and also breaks down the overall count into the numbers in each gender and life-history stage. The usefulness of the model is evaluated based on statistical model diagnostics.

Fire plays an important role in structuring and maintaining savanna grassland ecosystems. Although regular fires are a characteristic feature of savannas, the effects of fire frequency on these systems are less well known, particularly with respect to how frequency of fire influences large herbivore distribution and behaviour. The expectation is that large herbivores should be attracted to frequently burned sites as a consequence of changes in forage quality and quantity, and/or vegetation structure and composition. The former could be driven by alterations in soil nutrients, such as N and P. Alterations in vegetation also could be important in determining risk of predation. For example, an increase in woody vegetation could decrease predator visibility making large herbivores more vulnerable to predation. The objectives of this study were to investigate the effects of long-term alterations in fire frequency on herbivore distribution and behaviour, as well as the mechanisms (soil nutrients, vegetation structure and composition, and forage quality and quantity) potentially driving the distribution of large herbivores. To address these objectives, I conducted large herbivore surveys on a bi-weekly basis from 2009-2010 in a series of plots in the Experimental Burn Plots (EBPs) burnt at different frequencies (annual, triennial and unburnt) over the last five decades at three study sites in the Kruger National Park, South Africa. Surveys also were conducted on new plots that were established adjacent to the long-term plots. These new plots have a fire return interval of 4 years which is similar to the triennially burned plots of the EBPs. They were established in the landscape adjacent to the EBPs to assess whether the responses of herbivores to fire observed in the EBPs reflected was at landscape level. The distribution of all large herbivore species combined and of grazers (e.g. zebra) or browsers (e.g. kudu) only were not affected by fire frequency. In contrast, the abundance of mixed-feeders, such as impala, was significantly higher in the unburnt (control) and annually burned plots than the triennially burned plots. Although season did not have a significant impact on the distribution of browsers and mixed-feeders, overall more grazers were recorded across all burn treatments in the dry season compared to the wet season. Similar patterns of herbivore distribution were observed between the new plots and the triennially burned EBP plots, suggesting that responses observed to the long-term fire frequency treatments reflects herbivore responses at the landscape level. The long-term fire frequency treatments significantly affected soil nutrients (N, organic C, P, and K were significantly lower with annual burning), vegetation structure (abundance of woody plants were greater in unburned plots), and forage quantity (unburned plots had higher biomass) but not quality. More frequent fires improved visibility by reducing tree height and density and herbaceous biomass, thereby potentially reducing predation risk, when compared to less frequent burning. As a result, herbivores selected sites with more frequent fires. The behaviour of the herbivore species investigated was predominantly influenced by seasonal-induced changes to their environment rather than fire frequency. In the wet season irrespective of the burning treatment visibility was low due to high rainfall that increases plant biomass, whereas in the dry season visibility was improved because there is little to no rainfall. This potential alteration in predation risk likely resulted in herbivores being more vigilant in the wet season than the dry season. Overall, results from this study suggest that the combination of fire frequency and season drive herbivore distribution and behaviour by altering mainly the vegetation structure which can influence predation risk. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

Background : The recorded history of veld burning in the Kruger National Park (KNP) started with the appointment of Colonel James Stevenson-Hamilton as warden of the Park (then the Sabie Game Reserve) in July 1912 and can be divided into five periods: From 1912 to 1926, a haphazard, and indecisive burning policy was practiced, mainly due to the perception that fire was unfavourable for the environment and because the means to combat veld fires were very meagre. From 1926 to 1948, in which period it was realized that fire was not only unavoidable over a large area such as the KNP, but also actually desirable, necessary and beneficial when applied with circumspection. During this period the capability to successfully introduce and apply a definite fire policy did not exist. From 1948 to 1956, prescribed burning was not practiced, but a network of graded firebreaks was being established (to create burning blocks), and wild fires were actively combated. From 1957 to 1993, during which period a definite prescribed burning policy was practiced, amended several times, but basically consisting of a triennial rotational system where blocks were burned by management. All fires of non-management ignition sources were combated. From 1993 to the present, when a policy of allowing lightning-ignited fires to burn freely was introduced, and fires of human origin were suppressed. The shift away from a rigid prescribed burning programme was because of the concern that the dominance of grass species characteristic of over utilised veld was a result of too frequent burning (Potgieter, 2001). Lightning fires probably played just as an important role in shaping African savanna in pre-industrial times as anthropogenic fires caused by preindustrial man. The role of post-industrial man as far as its influence on the creation of savanna is concerned is probably negligible, but significantly important in the role of maintaining savanna, although probably not more so than that of lighting fires. Fires caused by postindustrial man becomes suspect as far as the creation of savanna is concerned, because instead of the mere burning of the veld for the pure reasons of survival as practiced by pre-industrial man, a measure of commercialism crept in (Potgieter, 2001). Fire management of the KNP in pre-industrial times can be regarded in the same light as that of post-industrial times. Although the motive for burning the veld in the KNP was beyond reproach, the underlying reasoning was not. Managers’ thinking was geared towards preventing so called “devastating fires”, laying to waste large areas of the Park, not realising that this was in actual fact nature going about its business in this ecosystem. They therefore devised a system of firebreak roads, which was gradually extended to the extent that we now have more than 4000 km roads that must be maintained. This was all in the cause of preventing or managing lightning and arson fires. Given the above, a revision of the veld fire policy was extremely necessary. The mission statement hammered out during the revising process in 1993 underscored and supported the proposal put forward in 1992, that lightning fires should be recognised as a legitimate and completely natural phenomenon in the Lowveld ecosystem. This had to be weighed against the prevailing practice of combating all fires caused by lightning and non-management anthropogenic sources of fire. The essence of this policy would therefore be to allow lightning-fires to burn to their full extent i.e. if vegetation conditions (available biomass) are such that large areas will burn, then such burns will be permitted to proceed to their full extent with the provision that no more than 50% of the management unit will be allowed to burn out (no matter what the ignition source) in a specific fire season (Potgieter, 2001).

Masters of Science / Understanding the hydrogeology of fractured or crystalline rocks is complicated because of complex structure and a porosity that is almost exclusively secondary. These types of geologies exhibit strong heterogeneities and irregularities contrasted in hydraulic properties, spacing and flow direction within fractured rock aquifers. Therefore it is important to develop a conceptual model based on site specific data such as the hydraulic roles between groundwater and nearby hillslope/surface water bodies in order to understand its movement within the environment. Therefore this study intends to develop a hydrogeological conceptual model associated with the dominant groundwater flow processes at a 3rd order scale within the Kruger National Park (KNP).

The structuring of ant assemblages in a Southern African savanna was investigated using data from the only long-term, large-scale savanna fire experiment in Africa. A comprehensive survey of three habitats in the Kruger National Park (KNP) revealed a total of 169 ant species from 41 genera. The sampling efficiency and consistency of pitfall traps and Winkler samples for inventory, bioindicator and ecological studies in savanna habitats was compared using ants. Pitfall traps were more efficient and productive than Winkler sampling for epigaiec ants, with a greater total species richness and higher abundance of ants recorded. Suggestions were made to improve Winkler sampling output, and to allow quantitative data to be collected. With the structuring of local assemblages, competition was the most significant local factor tested. The relationship between ant dominance and ant species richness was consistent across three continents. A model developed to test mechanisms that could be responsible for the form of this relationship supported the hypothesis that competitive exclusion by dominant ants at least partially reduces species richness. Stress was only partially responsible for low dominance and low species richness, while scatter in the data points is related to patchiness of ants at baits. These findings contrast strongly with previous claims regarding the relationship between richness and dominance. Habitat complexity was not found to play an important role in determining ant assemblage body size in this savanna system. The size-grain hypothesis (Kaspari&Weiser 1999) which predicts that environmental rugosity results in positive allometric scaling of leg length on body length because of changes in locomotion costs, was tested by comparing the body sizes of ants from areas of contrasting habitat complexity. No support for the hypothesis was found. Phylogenetic independent contrast methods did however support the allometric relationship found by Kaspari and Weiser (1999). Ant assemblages in KNP exhibited a remarkable degree of resistance, and in some cases resilience, to burning. Species richness or abundance did not vary with different burning treatments, although ant assemblage composition was sensitive to burning treatment. This difference, however, was only pronounced between burnt and unburnt plots, not between burning treatments. The degree of response of ant assemblages is likely to be related to two main contributory factors: mean annual rainfall and changes in vegetation structure with burning, and the assemblage's history of association with fire. An overview of published research on the effects of fire on fauna in Southern Africa was undertaken. Few studies have examined the effects of fire on amphibians or reptiles and few experimental studies have been undertaken using an experimental fire regime applied over appropriately long time intervals. Most studies provided no information on the scale of the study. Replication was often not reported, and was generally inadequate. Information on the effects of fire on fauna in Southern Africa is fragmentary, and consequently informed management decisions regarding the consequences of burning policies on the conservation of biodiversity both within and outside protected areas are problematic. Recommendations and suggestions for improving fire research are given. / Thesis (DPhil (Zoology))--University of Pretoria, 2005. / Zoology and Entomology / unrestricted

A description is given of a prevalence study of canine distemper virus antibodies in large carnivores in the Kruger National Park and Marakele National Park in South Africa. The serum-virus neutralization test was used to determine the prevalence of antibodies in different carnivore species in Kruger National Park and Marakele National Park. The species tested included 198 lions, 33 hyenas, 23 wild dogs and a leopard. The results demonstrated a total of 69 (34.8%) positive sera from lions. Moreover, CDV neutralizing antibodies were present in 25 (75.8%) hyena sera, 18 (78.3%) wild dog sera and the serum of one leopard. The results demonstrate that canine distemper virus is present in the Kruger National Park and that removal of the fences between the Kruger National Park and other conservation areas may pose a risk for spreading infectious diseases to susceptible species. Further work would be required to determine the prevalence of CDV in neighbouring regions. Only then risks can be estimated. Copyright / Dissertation (MSc)--University of Pretoria, 2010. / Veterinary Tropical Diseases / unrestricted

This study addresses the healthcare needs of employees and their families living in the Kruger National Park (KNP). A quantitative, explorative, descriptive research design was used to interview respondents who comprised of 75 male and female employees with children of various ages. The findings revealed that physical, psychological, environmental, socio-cultural, and behavioural needs of the employees and their families living in the KNP is probably unattainable as healthcare services are poorly distributed throughout the KNP, being mostly concentrated in the main camp of Skukuza. A number of respondents indicated that they required consultations about psychological and socio-cultural stresses in their lives. These services are not available in the KNP. / Health Studies / M.A. (Health Studies)

Invasive alien species are considered the second greatest threat to global biodiversity after habitat loss. South Africa is not immune from such threats and it is estimated that 10 million ha (8.28%) of land has been invaded to some extent by invasive alien species. Although South Africa has been invaded by several taxa, it is the effect of invasive trees and shrubs that has been environmentally and economically most damaging. The concerns raised due to the effects of biological invasion are not only restricted to off-reserve areas, but also protected areas where invasive alien organisms often pose a greater threat than habitat loss. Kruger National Park (KNP), South Africa’s flagship conservation area has been invaded by numerous plant taxa. The most damaging of these is Opuntia stricta (Cactaceae) and current sources estimate that the weed has invaded approximately 35 000 ha of conserved land, despite the initiation of a biological control programme against it. However, little is known about the effect of O. stricta on biodiversity in the KNP despite the large number of resources allocated to its eradication, including a successful biological control programme against it. In this study, I investigated the effect of O. stricta infestation on beetle (Order Coleoptera) and spider (Order Araneae) assemblages across four treatments of varying O. stricta infestation levels (heavy infestation, medium infestation, surrounded sites and pristine sites). Species characteristic of each treatment (indicator species) were identified using the indicator method. In addition, spiders were collected to gauge the effectiveness of three collecting methods (pitfall traps, leaf litter sifting and active searching) in a savanna characterized by O. stricta invasion. One hundred and thirty one spider species (1050 individuals) and 72 beetle species (2162 individuals) were collected in the treatments. I found no significant differences in species richness, species density and species assemblages for both beetles and spiders across the treatments. In addition, no beetle or spider species were found to be characteristic indicator species for a given treatment, which further indicates that arthropod assemblages are similar when compared across treatments. These results indicate that O. stricta does not appear to have a significant effect on beetle and spider assemblages at its current infestation level, possibly because of the similarity in vegetation structure across the treatments. Regarding spiders, different collecting methods captured different species and only 17% of the species were shared, indicating that the methods complement each other. Therefore, in order to sample the spider community, all three methods should be employed. Of the 131 spider species collected, 54 species (41%) are new records for the KNP. In light of the results, it is suggested that KNP’s successful biological control programme has played an important role in reducing the extent of the O. stricta infestation and should be continued to further mitigate the impacts of O. stricta. / Dissertation (MSc)--University of Pretoria, 2009. / Zoology and Entomology / unrestricted