Abstract: The Western Cape is a unique area to undertake research, due to the varying oceanographic conditions along the coast. These diverse environments create a hotspot for cetacean presence and diversity. This study aimed to collate and map distribution information of local whale and dolphin species in the Western Cape using citizen science. The first data chapter focused on obtaining opportunistic sightings from water users from scientific, platform of opportunity and sporadic sighting ...
Abstract: The fragmentation and loss of natural habitats brings about species losses. These losses may be amplified or reduced by the composition of the habitats surrounding remnant habitat fragments, i.e the matrix. The influence of the matrix on biological assemblages is, however, complex and poorly understood. Therefore, in this dissertation, I aim to determine whether matrix transformation influences bird assemblages within remnant natural habitat fragments and how patterns of bird diver...
Abstract: The southern tip of South Africa is characterised by two major current systems, each of which is associated with its own species. The southwest coastal waters represent the limit of the local or global distribution ranges of four of the eight cetacean species that most frequently occur in the area. The goal of the present study was to determine the fine scale distribution of these species and subsequently investigate which environmental factors influence and possibly limit their cu...
Abstract: Beta diversity, defined as the variation or turnover in species composition, is important to the understanding of how ecological communities assemble. Studies of beta diversity during secondary forest succession may thus afford the chance to understand community assembly from a known onset. This study examined the relationship between regeneration age and beta diversity within and between seral stages along a coastal dune forest successional sere for three taxa (trees, millipedes, ...
Abstract: Globally emphasis has been given to identify emerging and re-emerging pathogens. Rapid urban expansion creates a problem which is two-fold. Firstly, increasing slum living conditions due to inadequate rate of infrastructure development results in an increased reliance on natural resources, including the capture and consumption of surrounding wildlife to subsist, thereby facilitating the transfer of emergent zoonotic pathogens. Secondly, through activities such as pollution or alien...
Abstract: With catches of over 360,000 individuals, Antarctic blue whales Balaenoptera musculus intermedia were harvested to near extinction by commercial whaling in the past century. Antarctic blue whales are an important ecological component of marine ecosystems as they ensure the circulation of nutrients in the pelagic environment making such nutrients accessible for primary production. However, their recoveries; distributions; migrations; large-scale response to environmental variabiliti...
Abstract: Groups of translocated orphaned juvenile African elephants were studied in holding pens and following their release to assess how they re-organize and restructure socially by adopting roles, and if they show behavioural signs of stress. An adult female adopted a young individual. In all groups allomothering was observed to some degree. One 5 year old female prematurely assumed the role of leader and this role appears to be learned. Most groups established a linear dominance hierarc...
Abstract: This study was carried out in the eastern Transvaal Lowveld in an area 2 with a giraffe population density of 2,6 per km . Lions are the only predators and it was estimated that 48% of the calves die in their first year. The sex ratio departs significantly from unity in favour of females. Plant fragments in the rumen were identified. Giraffe subsist on the leaves of trees and shrubs, though fruit, flowers, twigs and grass were also utilised. Marked seasonal changes in the plant spe...
Abstract: Climate change is leading to loss of global and local biodiversity through changes in the ecology of fauna and flora. Changes in environmental temperature influence species distributional ranges. They respond by either migrating along with the shift in ecological zones or adapting to the new environmental conditions within a habitat. If neither adaptation nor migration is possible, local extinction of the species can result. This study was performed at Mariepskop mountain which ser...
Abstract: This thesis reports the findings of a fine-scale habitat selection study of Heaviside s dolphins (Cephalorhynchus heavisidii) at two sites in Namibia; Walvis Bay and Lüderitz. Walvis Bay and Lüderitz are the two largest embayments along the Namibian Coast, and therefore the two industrial ports in Namibia are located there. These bays are also inhabited year-round by Heaviside s dolphins, and, at Walvis Bay, a resident population of common bottlenose dolphins (Tursiops truncatus)...
Abstract: This study examined the sociality of two phylogenetically closely related otomyine, murid rodent species that display differences in social behaviour in the wild. A fundamental characteristic of sociality in mammals is the ability to recognise conspecifics and discriminate between familiar and unfamiliar animals. In rodents, olfactory cues serve as the main source of such recognition and has been linked to dopaminergic reward centres in the brain, structures and regions responsible...
Abstract: To improve the efficacy of protected areas in conserving ecological processes, initiatives such as the megaparks for metapopulations strive to increase connectivity between small and often isolated protected areas. Increasing connectivity between protected areas may mediate the apparent impact of elephants on vegetation and promote regional population stability through the spatial structuring of their populations. This relies on asynchronous population dynamics between interconnect...
Abstract: This thesis investigated the use of a static acoustic data logger known as a Cetacean and Porpoise Detection (C-POD) device for monitoring two species of dolphins that occur in Mossel Bay, South Africa: the Indo-Pacific bottlenose dolphin, Tursiops aduncus, and the Indian Ocean humpback dolphin, Sousa plumbea. These two species have a near shore distribution which brings them into frequent contact with human activities such as boating, fishing, desalination plants and the onshore c...
Abstract: As a result of climate change, environmental temperatures across southern Africa are predicted to rise by up to 5˚C by 2070. Elephants may be particularly vulnerable to these changes. Their small surface area to mass ratio and lack of sweat glands may impair heat loss. However, it is not known how elephants respond to high environmental temperatures (above 35˚C), limiting our ability to predict the responses of elephants to climate change. My study assessed these responses for th...
Abstract: Reproduction is the process whereby an animal ensures the continuous existence of their genes in the population by procreation. Reproduction presents a series of obstacles for both males and females. Males have to ensure they are in peak physical condition in order to establish dominance and compete for the attention of the opposite sex. Females need enough energy to support their bodily needs whilst supplying energy to the growing foetuses and suckling young. The current thesis in...