Natural & Applied Sciences

Natural & Applied Sciences Research Papers/Topics

Molecular detection and characterisation of potentially zoonotic bacteria in bathyergids from the Western Cape Province

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...

Acoustic assessment of the seasonal occurrence and behaviour of Antarctic blue whales Balaenoptera musculus intermedia in the southeastern Atlantic and Southern Oceans

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...

The development of social behaviour in translocated juvenile African elephants Loxodonta africana (Biumenbach)

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...

Studies on the biology and productivity of the giraffe giraffa camelopardalis

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...

The effect of long-term climate change on the vertebrate fauna of Mariepskop South Africa

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...

Spatial and temporal patterns of habitat use of Heaviside's dolphins in Namibia

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)...

Social recognition and telencephalic binding sites of oxytocin in a solitary and a social Otomyine species

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...

Environmental determinants of the movement patterns of elephants in the Kruger National Park

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...

Developing methods to use static acoustic click detectors for long term monitoring of coastal delphinids along the Cape south coast, South Africa

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...

The relationship between body and environmental temperatures in savanna elephants, Loxodonta africana

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...

The pattern of ovulation in females and effect of food restriction on male testicular development in the South African spiny mouse (Acomys spinosissimus)

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...

Behavioural thermoregulation in free-ranging savanna elephants (Loxodonta africana)

Abstract: Savanna elephants currently inhabit some of the hottest environments in Africa. Because of climate change, these environments are likely to get hotter. Due to their large body size and small body surface area to volume ratio, elephants may face difficulties in dissipating heat. Despite this suggestion, we do not understand how elephants in their natural environment respond to present day climatic extremes, which limits our ability to predict how elephants may respond to climate cha...

Behavioural and endocrine correlates to the mating system of the aardwolf Proteles cristata

Abstract: Mating systems are classifications of the outcome of individual strategies aimed at maximising reproductive success. These systems have two components; one describes how individuals socially relate and bond to mating partners and the other describes the genetic outcome of actual mating activities. Reproductive activity is under strong endocrine and behavioural regulation where inter-sexual discrepancies in the regulation of reproductive success have resulted in the majority of mamm...

Ecology of the Riverine Rabbit Bunolagus monticularis

Abstract: Aspects of the ecology of B. monticularis were studied with a view to the species' conservation. This investigation indicates that the present distribution is half that of the past distribution and that only one third of the original habitat remains uncultivated. It is estimated that this area could, theoretically, support 1435 rabbits. The shrubs, Pteronia erythrocaetha and Kochia pubescens constitute the bulk of the species' diet; grasses are included in the diet whenever rainfal...


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