Natural & Applied Sciences

Research Papers/Topics Natural & Applied Sciences

Avian nectarivory and pollination in Aloe marlothii Berger : interactions between bird communities and a winter-flowering succulent

Abstract: Aloe marlothii is a winter-flowering succulent that is widespread in the savanna biome of northern and north-eastern South Africa. Plants grow up to 8 m in height and are commonly found on rocky north-facing slopes. Nectar production occurs through a 24 h period with flowers producing copious amounts (c. 250 µl) of dilute nectar (c. 12%). This abundant nectar supply, that is available for a 5-10 week period during June-August, is utilised by numerous opportunistic avian nectarivor...

The ecology of the leopard (Panthera Pardus) in the Waterberg

Abstract: Although the opportunistic feeding habits of leopards were evident in this study, scat analysis showed that ungulates were by far the predominant food, with impala being the most frequent item. The fact that cattle calves were only taken up to ± 100 days old, emphasize the relevance of a proper stock management program to prevent stock losses. In addition, where such measures were impractical, temporary physical barriers such as electric fencing showed potential for application. M...

The feeding response of white-bellied sunbirds (Cinnyris [Nectarinia] talatala) to sugar concentration and viscosity of artificial nectar

Abstract: Plant nectar is a simple food and is easily digested by many different species of pollinators. Many compounds make up the composition of floral nectars, but the most abundant are sugars, generally dominated by sucrose and the hexoses, glucose and fructose. Nectar sugars have been measured for many plant species visited by hummingbirds, sunbirds and other passerines, revealing a range of concentrations. The nectars of passerine-pollinated flowers are generally dilute compared to tho...

Determinants of protected area boundary crossings by savannah elephants, Loxodonta africana

Abstract: When elephants leave primary protected areas (PPAs), such as national parks and game reserves, they may come into conflict with people residing on the adjoining land. In this study, I attempted to determine why African savannah elephants leave the PPAs in which they were collared. To accomplish this, I used telemetry locations of collared elephants in PPAs throughout southern Africa and investigated whether a range of intrinsic and extrinsic variables could explain why elephants cr...

An Atlas of hair from southern African mammal species with reference to its taxonomic and ecological significance

Abstract: ENGLISH: This thesis is a study of the microstructure of hair of southern African mammals, in particular of the Carnivora. It serves to fill a gap in knowledge of hair studies from this region, and points to the use of these studies in various fields. A major portion of the work is a hair atlas of southern African Carnivora, in which micrographs and coloured plates of hairs are presented with locality data and a descriptive text for each species. Although the findings of the atlas ...

Molecular and morphological assessment of invasive, inland Rattus (Rodentia: Muridae) congenerics in South Africa and their reservoir host potential with respect to Helicobacter and Bartonell

Abstract: Invasive species are generally problematic where they occur, especially in terms of ecology, economy and disease. Members of the genus Rattus Fischer, 1803 particularly, are known as one of the most destructive invasive species to date since they cause widespread damage on terrestrial and island ecosystems. Two Rattus species have historically been reported as invasive species in South Africa, Rattus rattus Linnaeus, 1758, which has a widespread distribution throughout the country ...

The functional significance of grooming behaviour in higher primates : the case of free-living chimpanzees

Abstract: As a contribution to the existing knowledge of grooming in primates five and a half years of grooming data were examined from a group of free-living chimpanzees (Pan troglodytes) in the Budongo Forest, Uganda, to investigate various functional significances of grooming behaviour within the context of social reinforcement. The fission–fusion social structure of chimpanzees results in group members not moving around as a single unit, but forming temporary units as the need arises. ...

The circadian system of African mole-rats : behavioural activity rhythms and early gene expression ( c-fos ) in the suprachiasmatic nucleus

Abstract: Mole-rats from the family Bathyergidae are endemic to Africa, this family exhibits a continuum of sociality, comprising both solitary and social species. Sociality is related to the degree of aridity and the distribution of the underground food resource. All the members of the bathyergid family are strictly subterranean, and occur in a niche which is devoid of light cues and thermally buffered from ambient and surface extremes. Since vision is redundant in a lightless environment, ...

Food quality, fasting periods and temperature stress : effects of energy challenges on the feeding patterns of avian nectarivores

Abstract: The small size of nectarivorous birds is associated with high mass-specific metabolic rates and energetic lifestyles. Their energy balance is likely to be strongly influenced by environmental factors. Firstly, nectar varies in sugar concentration between different food plants and birds must adjust their consumption to maintain a constant energy intake. Secondly, unfavourable weather conditions, such as storms and heavy rains, may prevent birds from feeding, and they must increase t...

Conservation assessment of South African mammals

Abstract: Clearly established conservation priorities are urgently required for taxa and ecosystems in critical need of conservation. This helps to identify and document taxa most in need of conservation attention, and provides an index of the state of degeneration of biodiversity. Including as much relevant information as possible in a prioritisation assessment will deliver the most accurate classification, yet these variables should not overly complicate the prioritisation process. Conserv...

Conserving wild dogs ( Lycaon pictus ) outside state protected areas in South Africa: ecological, sociological and economic determinants of success

Abstract: The restricted geographic range and tenuous conservation status of wild dogs in South Africa were the motivating factors behind this study. Wild dogs have been extirpated from most of their historic range in South Africa, and now occur in three limited distributions: a) one viable population in Kruger National Park; b) a protected meta-population, consisting of 1 packs in six sub-populations (four on state owned reserves – Hluhluwe-Umfolozi Park, Madikwe Game Reserve, Marakele Na...


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