Thesis (D.Sc.)(Zoology)--University of Pretoria, 1991. / Available on the Internet via the World Wide Web.

Centre of African Ecology Animal, Plants and the Environmental Sciences University of the Witwatersrand, Johannesburg. / Arid African savannas experience seasonal, variable rainfall, resulting in unpredictable patterns in vegetation distribution. Understanding the spatio-temporal variability in primary productivity and the resulting behavioural responses of native herbivores is essential for the analysis of the vulnerability of savanna ecosystems to climatic and human-induced threats. The Central Kalahari Game Reserve (CKGR), Botswana, is open to free-ranging wildlife to its south and west. The mostly homogeneous dune landscape is interspersed with valley and pan systems, which deviate considerably from dune regions in their soil and vegetation structures. I assessed the phenology of green vegetation across the pan-valley and dune habitats of the northern CKGR, using Normalized Difference Vegetation Index (NDVI) imagery, and related variations in greenness to the ecology of gemsbok (Oryx gazella), a herbivore species that is highly adapted to arid conditions. Eight female gemsbok were collared in the northern CKGR, and their patterns of habitat selection and responses to three greenness measures (NDVI, ΔNDVI and Relative Greenness) were assessed using logistic regression models. Gemsbok 12-hour displacement distances for each herd were compared seasonally to assess whether gemsbok in the northern CKGR differ in their movement strategies depending on the prevailing environmental conditions at that point in time and space. The northern CKGR experiences high inter-annual variability in NDVI greenness and phenology. Pan-valley and dune habitats did not have significantly different rates of green-up or green season durations, but dune habitats had higher NDVI levels. Patches with the highest greenness levels showed little spatial persistence from year to year. Gemsbok did not select for higher NDVI or ΔNDVI, but they selected for categories of relative greenness that were higher than the lowest relative greenness level. Gemsbok selected pan-valleys over dunes during the green season, but were not selective during the brown season, probably as a result of the loss of green grasses in pan-valley habitats during this period. Finally, gemsbok had no specific general trend in seasonal displacement distances. Gemsbok in the CKGR are likely to be opportunistic feeders, and herds probably made varying behavioural decisions based on their immediate environmental conditions.

Thesis (M.Sc. (Zoology)) --University of Limpopo, 2012 / A microsatellite-based study was performed on five populations of Gemsbok (Oryx gazella). This study was aimed at estimating genetic diversity in introduced South African gemsbok populations (an opportunity that arose when additional animals from the same source were imported into South Africa), and determine genetic structure. Population sizes at the time of sampling were: Namibia (n = 6500), Cohen (n = 70), Tempelhof (n = 55), STS Kalahari Game Ranch (n = 1000) and Elias (n = 35). The purpose of the study was to determine the genetic structure of the aforementioned O. Gazelle populations, and to assess the impact of the founder effect on isolated populations. The following primers (BMS1237, MAF46, OARFC304, OARHH64, ETH225, RBP3, MAF50, HDZ8) developed for commercial purposes in the bovine group were used. Genetic diversity were calculated as Expected Heterozygosity (He), proportion of polymorphic loc (P) and number of alleles per locus (A). Conformation to expected Hardy-Weinberg equilibrium of genotypes was also determined, using a Chi-square test. Tests for the signature of bottlenecks in the populations studied were also performed. Genetic drift/differentiation was tested by using FST and RST coefficients. Assignment tests were performed to identify the true number of genetic populations (clusters). Genetic distance was used as an additional measure of differentiation. The results indicated that all loci showed allelic polymorphism in all the populations except one (at the OARHH64 locus). The South African Cohen population displayed the highest level of genetic diversity, with He = 0.595 ± 0.247. This population also did not show evidence of a bottleneck. Genetic distance values indicated the greatest similarity between the Cohen and Namibian populations, in line with the Namibian origin of the Cohen group. Greatest distance was observed between the STS and Tempelhof populations. conclusion, results from this study reflects the origins of populations and suggest that inbreeding in small isolated populations may be less than previously estimated.

Thesis (MTech (Nature Conservation))--Cape Peninsula University of Technology, 2016. / Lions are threatened across their natural range. The Kgalagadi Transfrontier Park (KTP), comprising the Kalahari Gemsbok National Park (KGNP; South Africa) and Gemsbok National Park (GNP; Botswana), is a stronghold for the species. Population size and demography of lions in the KGNP has been addressed in four historic studies. Studies in mid-1970 and 1990 reported a female biased population whereas in 2010 the sex structure was skewed towards males (56%). The bias in sex ratios towards males was first observed in cubs and sub-adults in 2001 and later, in 2010, throughout the population. Furthermore, in the 2010 assessment of the lion population, a smaller proportion of cubs (< 2 yrs) were observed in comparisons to the preceding studies (10% vs. ≥ 23%). The skew in age and sex structures that were observed in the KGNP led to concerns over the long-term sustainability of the greater KTP lion population. The lion population carries further risks associated with the stochastic, arid environment, in which the KTP lion population persists. Human-lion conflict on the borders of the KTP and anthropogenic alterations of the environment further threaten lion demographic stability.

A research report submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Science Johannesburg, August 2015 / The central Kalahari is likely to become hotter and drier as a result of climate change in the region. These changes may result in behavioural changes in Gemsbok due to temperature induced stress, in spite of physiological and behavioural adaptations, and are likely to manifest in a preference for particular landscape patch classes. Recent Landsat 8 satellite imagery and classification analysis were used to map landscape patch classes in a heterogeneous landscape in the central Kalahari. The classification map of the research area identified 6 classes of landscape patches used by Gemsbok. Eight collared Gemsbok were tracked by satellite to monitor their movement in their respective home ranges over a period of 9 months. Gemsbok locations were plotted on to the classification map, and location frequency distributions were produced for each landscape patch class. Gemsbok home ranges were calculated using minimum convex polygon geometry, and the available patch class areas within each home range were analysed against the usage patterns of each animal. The analysis showed less preference for shade producing classes and more preference for open classes. Exploration of the role of temperature in landscape patch selection showed that temperature is a weak predictor of patch class, that critical temperature thresholds have not yet been reached, and that Gemsbok preference for pans is more likely related to seasonally available forage and reduced predation risk in a “landscape of fear” (Laundré, Hernández, & Altendorf, 2001).

A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of requirements for the degree of Master of Science. Johannesburg, 2016. / This project investigates the influence that rainfall and temperature patterns have on mammal drinking patterns at an artificial waterhole in KGNP at Nossob. On a regional scale, this project investigates long-term rainfall and temperature trends over three/four decades, and in some instances the past 100 years, respectively for KGNP using climate records from weather stations located within the park and adjacent areas. This project makes use of KGNP census data to observe spatio-temporal distributions of large mammals in relation to rainfall (and to a lesser extent temperature) variability. Investigations assess whether relationships exist between faunal movement and distribution and rainfall volume and frequency. On a local scale, this project makes use of webcam images measured at 15-second intervals to establish mammalian drinking patterns and waterhole use over a short time scale (October 2012 – December 2014). The climate data for Twee Rivieren, Mata-Mata, Nossob and Upington reveal statistically significant increases in Tmax (av. 0.04°C) over the study period, whilst in summary, mean regional temperatures have increased by almost 1.6°C over the past 40 years. Rainfall patterns have revealed a north to south gradient in KGNP, where the northern and central parts of the park are becoming drier and the southern parts are becoming wetter. This demonstrates rainfall variability throughout KGNP over the period 2004 - 2013. This study established a positive relationship between faunal distributions and rainfall patterns within the park, showing that certain species are highly reliant on rainfall as a source of drinking water. It has been established that herbivore species are more reliant on the water trough during the dry season, when surface water is not available. However, there is an even spread of carnivore species water trough usage during the wet and dry season throughout the year. It has been established that during rainfall events exceeding ca. 30mm, faunal species prefer to utilise the natural surface water rather than the artificial waterhole at Nossob. Water trough usage under different temperature thresholds has revealed that groups of species (carnivores and herbivores) drinking patterns shift to either earlier or later in the day when temperatures increase, in order to avoid heat stress. Changing rainfall patterns could drastically cause water shortages, which will negatively affect the amount of available drinking water for mammals within KGNP. This study is important in contributing to an improved management of KGNP through providing a quantitative description of the relationship of mammal visitation at water troughs to the ambient climate. This is particularly valuable as climate change projections for the region suggest progressive drying. Water troughs will become an important source of moisture. / LG2017

The Gemsbok Sub-basin is situated in the south-western corner of the Kalahari Karoo Basin and extends south from the Kgalagadi District of Botswana into the Northern Cape (South Africa); and west into the Aranos Basin (southeast Namibia). The Sub-basin preserves a heterogeneous succession of Upper Palaeozoic to Lower Mesozoic sedimentary and volcanic rocks of the Karoo Supergroup. Because the succession is largely covered by the Cenozoic Kalahari Group, the stratigraphy of the succession is not as well understood as the Main Karoo Basin in South Africa. Most research in the Gemsbok Sub-basin is based on borehole data. This study focuses on the intrabasinal correlation, depositional environments and provenance of the Karoo Supergroup in the Gemsbok Sub-basin in Botswana and Namibia. Based on detailed sedimentological analyses of 11 borehole cores of the Karoo Supergroup in the Gemsbok Sub-basin of Botswana and Namibia, 8 facies associations (FAs) comprising 14 lithofacies and 2 trace fossil assemblages (Cruziana and Skolithos ichnofacies) were identified. The facies associations (FA1 to FA8) correspond to the lithostratigraphic subdivisions (the Dwyka Group, Ecca Group, Beaufort equivalent Group, Lebung Group [Mosolotsane and Ntane formations] and Neu Loore Formation) of the Karoo Supergroup. Sedimentological characteristics of the identified facies associations indicate the following depositional environments: glaciomarine or glaciolacustrine (FA1, Dwyka Group), deep-water (lake or sea) (FA2, Ecca Group), prodelta (FA3, Ecca Group), delta front (FA4, Ecca Group), delta plain (FA5, Ecca Group), floodplain (probably shallow lakes) (FA6, Beaufort Group equivalent), fluvial (FA7, Mosolotsane and Neu Loore formations) and aeolian (FA8, Ntane Sandstone Formation). The Dwyka Group (FA1) forms the base of the Karoo Supergroup in the Gemsbok Subbasin and overlain by the Ecca Group deposits. Three types of deltas exist within the Ecca Group: fluvial-dominated; fluvial-wave interaction and wave-dominated deltas. The Gemsbok Sub-basin was characterised by rapid uplift and subsidence and high sediment influx during the deposition of the Ecca Group. Petrographic and geochemical analyses of the Ecca Group sandstones revealed immature arkose and subarkose type sandstones dominated by angular to subangular detrital grains, sourced from transitional continental and basement uplifted source areas. The sandstones of Ntane Sandstone Formation are classified as subarkoses and sourced from the craton interior provenances.

Thesis (MTech (Nature Conservation))--Cape Peninsula University of Technology, 2016. / A survey in 2010 suggested that the lion (Panthera leo) population of the Kalahari Gemsbok National Park (KGNP) was exhibiting a skewed sex ratio in favour of males, which can ultimately lead to a decline in lion population numbers. In the KGNP artificial water provision has influenced the abundance of resident prey and potentially, lion diet and body condition. Changes in mammalian diet, and consequently body condition, have been found to influence the sex ratio of offspring. In response to a concern that diet may be influencing lion sex ratios in the KGNP, aspects of the spatial and temporal variation in lion diet were investigated between May 2013 and June 2015. The lion diet profile in the KGNP was described using evidence of prey remains identified through GPS cluster analysis (n = 278) from seven collared lionesses, lion scat analysis (n = 189) and opportunistic observations of lion feeding events (n = 52). Spatial variation in diet was investigated between three regional landscape types (north, south and west), based on the different vegetation types represented within each area, and two habitat types (riverbeds and dunes). Seasonal variations were assessed according to the hot-wet season (November to April), and the cold-dry season (May to October). Findings were also used to assess whether lion diet in KGNP has changed over the last 45 years through evaluating results from historical lion diet studies.

Please read the abstract (Uittreksel) in the section, 00front of this document. See also 10summary / Dissertation (MSc (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / MSc / unrestricted

Thesis (PhD (Food Sc))--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The wildlife industry in Namibia has shown tremendous growth over the past decades and is currently the only extensive production system in Namibia that is expanding. Harvesting game for the purpose of meat production is a viable option since there is a worldwide demand for healthy and high quality proteins. The main objective of the dissertation was to investigate selected parameters required to develop a sustainable Namibian game meat industry. The major species suitable for commercial harvesting operations are springbok (Antidorcas marsupialis – Zimmerman, 1780), gemsbok (Oryx gazella – Linnaeus, 1785), kudu (Tragelaphus strepsiceros – Pallas, 1766), mountain zebra (Equus zebra hartmannae – Linnaeus, 1758) and red hartebeest (Alcelaphus buselaphus caama – Pallas, 1766). Eland (Tragelaphus oryx – Pallas, 1766) could be considered as a suitable species, although the numbers of animals that can be harvested during an operation are limited. This study demonstrated that gender influenced live weight of springbok, kudu and red hartebeest. Gender also influenced carcass weights for springbok, gemsbok, kudu and red hartebeest, but not for eland, while dressing percentage did not differ between gender for springbok, gemsbok, kudu and red hartebeest. Although there were some statistical differences in the chemical composition of the various muscles from the different species (Mm. biceps femoris, infraspinatus, longissimus dorsi, semimembranosus, semitendinosus and supraspinatus), it is doubtful whether consumers would be able to distinguish between these. Discriminant analysis could not differentiate among the different muscle groups for springbok and gemsbok. A differentiation was, however, revealed among the various muscles for red hartebeest. During the investigation on the influence of season and gender on the carcass yields and meat quality characteristics of kudu and red hartebeest, dressing percentage was affected by season, but not by gender. Muscle colour differed significantly between seasons. Results from this study showed that male eland contained more saturated fatty acids than females, but no gender differences were observed for polyunsaturated fatty acids. Hides of gemsbok, kudu and red hartebeest contributed 6 – 7% of live weight, while the skin of springbok contributed 4 – 5% of live weight. Comparisons of offal items among species showed significant differences for all offal items, except for intestines. Retail cuts showed significant species difference for rump, topside, silverside and sinews. No significant species differences were observed for thick flank and bolo. Significant gender differences were observed for silverside. No interactions between species and gender were found for the different retail cuts from gemsbok and kudu. Microbiological counts of game meat, chilled for 6 weeks and frozen for 12 months, respectively, were found to be within acceptable limits as prescribed by the South African retail market. Differences in physico-chemical and microbiological properties were observed among salami from different game species. The springbok salami was found to be microbiologically unstable. The main characteristics observed while tasting the salami from springbok, gemsbok, kudu and zebra were a distinctive smoky, salty, pepper and salami flavour combined with a smoky, salami aroma. Game flavour did not feature as strong during the sensory analyses. Sustainable utilization of game for commercial meat production has the potential to increase earnings to beneficiaries in the wildlife sector. Results from this study contributed knowledge which can be utilized to develop the Namibian game meat industry. / AFRIKAANSE OPSOMMING: Die wildsbedryf in Namibië het die afgelope dekades buitengewone groei getoon en is huidiglik die enigste ekstensiewe produksie-sisteem wat in Namibië uitbrei. Die oes van wild is ʼn voordelige opsie, aangesien daar wêreldwyd ʼn aanvraag is na gesonde en hoë kwaliteit proteïene. Die hoofdoelwit van hierdie dissertasie was die loods van ʼn ondersoek na geselekteerde aspekte wat benodig word om die Namibiese wildsvleisbedryf te ontwikkel. Die belangrikste spesies geïdentifiseer as geskik vir kommersiële oes, is springbok (Antidorcas marsupialis – Zimmerman, 1780), gemsbok (Oryx gazella – Linnaeus, 1785), koedoe (Tragelaphus strepsiceros – Pallas, 1766), berg sebra (Equus zebra hartmannae – Linnaeus, 1758) en rooihartbees (Alcelaphus buselaphus caama – Pallas, 1766). Eland (Tragelaphus oryx – Pallas, 1766) is ook ʼn geskikte spesies, maar die hoeveelhede wat op een slag geoes kan word, is beperk. Hierdie studie het gedemonstreer dat geslag ʼn invloed op die lewendige gewig van springbok, koedoe en rooihartbees het. Geslag het ook ʼn invloed gehad op karkasgewigte van springbok, gemsbok, koedoe en rooihartbees, maar geen invloed op die karkasgewig van eland nie, terwyl uitslagpersentasie geensins geslagsverskille getoon het vir springbok, gemsbok, koedoe of rooihartbees nie. Nieteenstaande statistiese verskille in die chemiese samestelling van die verskillende spiere van die onderskeie spesies (Mm. biceps femoris, infraspinatus, longissimus dorsi, semimembranosus, semitendinosus en supraspinatus), is dit te betwyfel of verbruikers ʼn onderskeid sal kan tref tussen die spiere. Diskriminant-analise kon nie verskille uitwys tussen die verskillende groepe spiere van springbok en gemsbok nie. Verskille was egter te bespeur tussen verskillende spiere van die rooihartbees. Gedurende hierdie ondersoek is die invloed van seisoen en geslag op die karkasopbrengs en vleiskwaliteit van koedoe en rooihartbees ondersoek. Uitslagpersentasie is beïnvloed deur seisoen, maar nie deur geslag nie. Kleur het betekenisvol verskil tussen seisoene. Resultate van die studie het getoon dat elandbulle meer versadigde vetsure het as koeie, maar dat geen verskille vir geslag gevind is vir poli-onversadigde vetsure nie. Gemsbok-, koedoe - en rooihartbeesvelle het 6 – 7% bygedra tot die lewendige gewig, terwyl die vel van die springbok 4 – 5% bygedra het. Vergelykings van afvalopbrengs tussen spesies het verskille uitgewys ten opsigte van al die items, behalwe die ingewande. Kleinhandelsnitte het betekenisvolle verskille getoon vir die kruis, binneboud, dy en senings. Geen betekenisvolle spesies verskille is opgemerk vir die diklies en bolo nie. Die dy het betekenisvolle verskille tussen geslagte getoon. Geen interaksie tussen spesies en geslag is opgemerk vir die verskillende kleinhandelsnitte van gemsbok en koedoe nie. Mikrobiologiese tellings vir wildsvleis, verkoel vir 6 weke en gevries vir 12 maande, onderskeidelik, het voldoen aan die aanvaarbare vlakke soos voorgeskryf deur die Suid-Afrikaanse kleinhandelsmark. Verskille in fisiese, chemiese en mikrobiologiese kwaliteite was opgemerk vir die salami van die verskillende spesies. Springbok salami was mikrobiologies onstabiel. Die belangrikste karaktereienskappe bemerk tydens die proe van die salami vervaardig van springbok-, gemsbok- , koedoe - en sebravleis, was ʼn oorheersende rook-, sout-, peper- en salamigeur, gekombineer met ʼn rook- en salami aroma. Wildsvleisgeur het nie sterk na vore gekom tydens die sensoriese analise, nie. Die volhoubare gebruik van wild vir kommersiële vleisproduksie het die potensiaal om inkomste vir belangegroepe in die wildsektor te verhoog. Resultate van hierdie studie het kennis uitgebrei wat gebruik kan word om die wildsvleisindustrie in Namibië te ontwikkel.