Abstract: The social reproductive inhibition evident in female common (Cryptomys hottentotus hottentotus) and highveld (Cryptomys hottentotus pretoriae) mole-rats was investigated, focussing on intra- and inter-subspecies differences in gonadotropin¬releasing hormone (GnRH) neuroanatomy and neuroendocrinology and potential mechanisms mediating social infertility through the suppression of luteinizing hormone (LH) and/or GnRH synthesis or release. The molecular structure of the GnRH peptide ...
Abstract: People and elephants share landscapes throughout Mozambique. Here elephant conservation management focuses on protected areas but fails to address the conflict that exists between elephants and people. In this thesis I develop a landscape approach to conflict mitigation that is designed to accommodate the needs of people and of elephants in human-dominated landscapes. Mozambique faces a dilemma: politically it is required to reduce poverty while at the same time adhere to internati...
Abstract: A holistic evolutionary approach is used in the Gorongosa thesis in which emphasis is on the salient reciprocal relations and kinetic succession of land surfaces and biotic communities, influenced by landscape processes and prime mover components. As correlations of these relations and processes require both a total interacting framework and the details of its prime components, the thesis is divided into three main parts: (1) synopsis of the essence of the Gorongosa ecosystem and t...
Abstract: Please read the abstract in the section 08summary of this document
Abstract: Bats inhabiting arid, subtropical environments face diverse challenges related to energy and water balance. First, they may have to conserve water and energy during cool, dry winters when water is scarce and insect availability reduced. Second, during hot summers when air temperature may routinely exceed body temperature, bats may need to avoid both hyperthermia and dehydration. A common response to the energetically challenging winter period in temperate, subtropical and tropical ...
Abstract: In this thesis, I investigated the relationship between host and pathogen in multi-host and multi-pathogen systems at the interface between wildlife and domestic species. The term “epidemiological interaction” was central to my thesis, and was defined as “any ecological interaction between two host populations resulting in the transmission of one or more pathogen”. Epidemiological interactions are related to the processes of transmission between hosts and I investigated how...
Abstract: Please read the abstract in the section, 09summary, of this document
Abstract: The responsiveness of South African fauna to climate change events is poorly documented and not routinely incorporated into regional conservation planning exercises. The lack of detailed distribution data for appreciable numbers of taxa demands a modeling solution. We develop a climate envelope model to predict potential distribution range changes. The model can be used to interpolate the distributions of poorly sampled taxa as well as predict responses to a changing climate. It is...
Abstract: The distributional range of the Tete veld rat, Aethomys ineptus, extends from the Limpopo Province in the north through to the south of KwaZulu Natal. The Tete veld rat is a seasonal breeder, with the breeding period confmed to the wet summer months of the year in the Gauteng Province of South Africa. The seasonality of reproduction in the Tete veld rat is confirmed by reproductive tract morphometrics, ovarian histology, plasma progesterone, and oestradiol-17β in females, and test...
Abstract: The aim of this study was to investigate various aspects of the life history of white sharks Carcharodon carcharias at Dyer Island, South Africa, between August 1999 and January 2001. Inter-specific predatory interactions between the white shark and various potential prey species such as the Cape fur seal (Arctocephalus pusillus pusillus), African penguin (Spheniscus demersus), Cape cormorant (Phalacrocorax capensis), bank cormorant (P. neglectus), crown cormorant (P. coronatus) an...
Abstract: Life-history features of terrestrial mammals in the southern African subregion were explored in an attempt to identify the factor(s) that may influence the evolution of common mammalian life-history patterns within this subregion. Allometry and phylogeny were found to underly most of the variation observed in life-history features. Residual variation was considered and age at maturity, gestation period and litter size emerged as additional features influencing life-history patterns...
Abstract: Please read the abstract in the section 00front of this document
Abstract: Please read the abstract in the section 00front of this document
Abstract: Researchers use changes in bird community composition to illustrate ecological succession in restoration studies. These studies utilise a variety of methods, some of which may bias their outcomes. Here I used the point and line transect methods to obtain community compositions as well as to estimate total density, species richness and species diversity for bird communities living in a successional sere of coastal dune habitats. The two methods yielded similar estimates of community...
Abstract: Field data were collected and analysed on the feeding and spatial ecology of brown hyaenas living in the Makgadikgadi National Park and in an adjacent Wildlife Management Area where local subsistence pastoralists live. The responses of the pastoralists to a questionnaire designed to document their perceptions of and attitudes towards brown hyaenas and other carnivores that live in the vicinity of their residences, were also analysed. Brown hyaenas living in the Makgadikgadi Nationa...