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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Assessing the diet of the Cape leopard (panthera pardus) in the Cederberg and Gamka mountains, South Africa

Rautenbach, Therèsè January 2010 (has links)
As limited prey availability and persecution by humans in response to livestock predation are key conservation concerns for the Cape leopard (Martins & Martins 2006), the present study aimed to provide more information regarding their feeding habits. The first objective was to determine whether the Cape leopard was subject to a change in their prey base and how they responded to the change. This was established by comparison of their current diet in the Cederberg and Gamka Mountains, determined by using scat analysis techniques, with a previous dietary assessment (Norton et al. 1986). The second aim was to provide a preliminary assessment of the prey preference of the Cape leopard and examine the utility of camera trap surveys to determine leopard prey preference. Leopard diet in the Cederberg and Gamka Mountains consisted largely of small- (1-10 kg) and medium-sized (10-40 kg) mammals; rock hyraxes (Procavia capensis) and klipspringers (Oreotragus oreotragus) were key prey items. In terms of regional variation in leopard diet, there was a significant difference in the average weight of prey utilized in the Cederberg and Gamka Mountains. Despite the importance of prey availability of suitable size, their flexibility in terms of prey size utilization reflected their ability to switch to smaller prey to fulfil their dietary requirements, when prey is limited. The study suggested a dietary shift, with significant variation in prey species utilization in both regions. The shift did not appear to be in response to prey scarcity, but rather a reduction in key prey species, particularly the rock hyrax. The shift involved an increase in the number of species utilized, and only a very small increase in livestock predation in both areas. There was however no significant variation in prey size category utilization. This demonstrated their dietary flexibility, as well as the importance of suitable prey sizes rather than the presence of specific prey species to fulfil their dietary requirements. The camera trap survey revealed a strong correlation between the number of camera trap days and the number of photographs taken of identifiable species. Variation of this correlation between different habitats supported the notion that individual images are a better unit to determine sampling efficiency than trap days. The camera trap survey also showed that small rodent availability was underestimated by camera trap surveillance, which resulted in poor prey preference estimation. It was therefore suggested that camera trap surveys be restricted to the surveillance of larger prey species (> 1 kg). By excluding small rodents from the analysis, prey preference could be estimated for other species and prey size categories. Small- and medium-sized mammals were significantly preferred, whereas large mammals were significantly avoided by the Cape leopard.
2

Farmers` perceptions of livestock feeding and rangeland management: dynamics of soil, forage and cattle blood serum mineral levels in two communal areas of the Eastern Cape, South Africa

Gwelo, Farai Alice January 2012 (has links)
This study was conducted to determine livestock production, rangeland management and the mineral levels of soils, grass and cattle blood serum in two communal areas (Kwezana and Dikidikana). A total of 77 farmers from both Kwezana and Dikidikana were interviewed to determine farmers’ perceptions. Soil and grass sampling was done at three sites in each communal area. Soil and grass samples were analysed for N, Ca, Mg, K, P, Fe, Cu, Zn, Mn and Bo. Three, two and half year old Nguni heifers were randomly selected from each communal area and blood samples were collected for the analysis of Ca, Mg, K, Cu and Fe. Soil, grass and blood samples were all collected in two seasons (winter and summer). The results of the study revealed that feed availability was the major constraint in livestock production as indicated by 83 percent of thefarmers at Kwezana and 88 percent at Dikidikana. At both villages less than 20 percent practiced supplementation and grazing management. From both villages, 83 percent of the farmers did not know the forage species preferred by their cattle. The second study revealed significant seasonal variations in soil N in both study areas while forage N exhibited seasonal variations (P<0.05) only at Dikidikana. Spatial variation (P<0.05) in soil Mn was apparent in both seasons at Dikidikana and in summer at Kwezana. At Dikidikana forage P varied (P<0.05) both seasonally and spatially. In both study areas, there was a positive correlation (P<0.05) between soil and forage levels of Cu and Zn. The blood serum of animals from both study areas had higher (P<0.05) K and Na in winter than in summer. Farmers do not understand the composition of their rangelands but are concerned about cattle nutrition during winter. Indeed the mineral status of soils, forages and Nguni cattle blood serum tend to vary not only seasonally but also spatially. There is need therefore to assist the farmers to understand these changes in order to find ways of managing the rangelands in a way that will manipulate both seasonal and spatial variations in soil nutrients for the benefit of the grazing livestock. Further research is required to determine the digestibility of the forages and the amount of energy available from these forages for the grazing livestock.

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