Natural & Applied Sciences

Research Papers/Topics Natural & Applied Sciences

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...

Intracolonial demography, biomass and food consumption of Macrotermes natalensis (Haviland) (Isoptera: Termitidae) colonies in the northern Kruger National Park, South Africa

Abstract: This thesis reports on the number of individuals in Macrotermes natalensis (Hav.) colonies, their biomass and food consumption in the northern Kruger National Park (KNP). The ecology of M. natalensis is largely undocumented despite the abundance of colonies in southern African savannas. New approaches to mound excavation, sub-sampling and data management are introduced. Via the intracolonial demography of colonies the contribution of each caste in number or proportion is determined...

Molecular phylogeny and evolution of the Ectemnorhinus group of weevils in the Prince Edward Islands

Abstract: All previous taxonomic studies on the Ectemnorhinus group of weevils have been based primarily on morphological data. While these studies are invaluable, some questions can only be addressed adequately through molecular studies. This is especially true when studying the genetic relationships and phylogeograpic patterns of taxa endemic to the South Indian Ocean Province (SIP) biotas that have long been controversial. The Ectemnorhinus group of genera is a monophyletic unit of weevil...

The ecology and conservation of Juliana’s golden mole (Neamblysomus julianae)

Abstract: Despite an IUCN conservation status of critically endangered, Juliana’s golden mole (Neamblysomus julianae) has received no ecological research attention to date. The species urgently requires conservation attention, but a poor understanding its biology, ecology and distribution makes effective conservation planning almost impossible. In light of this, a thorough understanding of the habitat requirements for this habitat specific species was needed. Additionally, the cryptic life...

Dispersal and dispersion of southern elephant seals at Marion Island

Abstract: This study focused on the dispersal and dispersion of southern elephant seals, Mirounga leonina, at Marion Island in relation to their natal site, and to their site of first reproduction. Movements from the natal site to terrestrial haulouts used for reproduction, and between successive reproductive sites, were defined as dispersal, while movements from the natal site to sites used for purposes other than reproduction, were defined as dispersion. Some 33000 records collected over 1...

Movement analysis for monitoring predation by large carnivores : lions in Kruger National Park

Abstract: Methods used to estimate the prey consumption by large carnivores include direct continuous observation, stomach content analysis, carcass observations and scat analysis. Continual observations are widely considered the best approach to estimate large carnivore diets, with lions (Panthera leo) being no exception. Continual observation allows the recording of all prey encounters and biases inherent in the other approaches are minimised. However, continuous observations are not alway...

A morphological analysis of weevils from sub-Antarctic Prince Edward Islands: an assessment of ecological influences

Abstract: The ecologically sensitive, but relatively simple sub-Antarctic mouse-colonised Marion and mouse-free Prince Edward Islands represent ideal ecosystems for addressing questions relating to the partitioning of potential influences of anthropogenic changes, such as climate change and alien species on ecosystem functioning. Consequently, weevil species were used in the present investigation to address questions of morphological change over time with reference to climate change and mous...

Physiological and microbiological studies of nectar xylose metabolism in the Namaqua rock mouse, Aethomys namaquensis (A. Smith, 1834)

Abstract: Xylose is an unusual nectar sugar found in the nectar of Protea and Faurea (Proteaceae). Since nectar composition is an important floral characteristic in plant strategies for ensuring reproductive success, the unexplained presence of xylose in Protea nectar prompted this study of the interaction between pollinators and Protea species. Among pollinators that visit Proteaflowers in the south-western Cape Floral Kingdom, South Africa, insects and birds show an aversion to, and are po...


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