Johannesburg, South Africa
Johannesburg, South Africa

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Johnson S.,Queensland University of Technology | Mengersen K.,Queensland University of Technology | de Waal A.,South African Council for Scientific and Industrial Research | Marnewick K.,Carnivore Conservation Group | And 4 more authors.
Ecological Modelling | Year: 2010

Relocation is one of the strategies used by conservationists to deal with problem cheetahs in southern Africa. The success of a relocation event and the factors that influence it within the broader context of long-term viability of wild cheetah metapopulations was the focus of a Bayesian Network (BN) modelling workshop in South Africa. Using a new heuristics, Iterative Bayesian Network Development Cycle (IBNDC), described in this paper, several networks were formulated to distinguish between the unique relocation experiences and conditions in Botswana and South Africa. There were many common underlying factors, despite the disparate relocation strategies and sites in the two countries. The benefit of relocation BNs goes beyond the identification and quantification of the factors influencing the success of relocations and population viability. They equip conservationists with a powerful communication tool in their negotiations with land and livestock owners, which is key to the long-term survival of cheetahs in southern Africa. Importantly, the IBNDC provides the ecological modeller with a methodological process that combines several BN design frameworks to facilitate the development of a BN in a multi-expert and multi-field domain. © 2009 Elsevier B.V. All rights reserved.


Thorn M.,University of Brighton | Green M.,University of Pretoria | Keith M.,University of Witwatersrand | Marnewick K.,University of Pretoria | And 4 more authors.
ORYX | Year: 2011

Accurate assessment of carnivore population status is frequently hindered by insufficient distribution data. For northern South Africa we address this deficit by mapping new records from landscape-scale sign surveys, questionnaire interviews, problem animal records and camera trapping. The black-backed jackal Canis mesomelas and caracal Caracal caracal remain common and widespread. Ranges of the serval Leptailurus serval and brown hyaena Hyaena brunnea were much larger than previous estimates, reducing the risk of simultaneous extirpation across all occupied locations. The proportion of range area occupied was larger for several species, notably the leopard Panthera pardus, cheetah Acinonyx jubatus and serval. We conclude that the serval continues to recover from historical threats and is expanding into new areas. A larger brown hyaena range and less fragmented pattern of occurrence probably confers greater resilience to threats than was suggested by previous data. Reduced extinction risk arising from the increased area occupied by the cheetah and leopard is tempered by probable local range contraction. Our maps provide baseline information for monitoring the distribution of these six species, which is essential in managing ecological issues that have a spatial component such as responses to changing land use. Our results also demonstrate the utility of detection/non-detection surveys in rapid assessment of carnivore populations at large spatial scales. © 2011 Fauna & Flora International.


Herbst M.,University of Pretoria | Herbst M.,Carnivore Conservation Group | Mills M.G.L.,University of Pretoria | Mills M.G.L.,Tony and Lisette Lewis Foundation
Koedoe | Year: 2010

The techniques used for the capture, marking and habituation of African wildcats (Felis silvestris cafra) in the Kalahari are described and evaluated in this paper. African wildcats were captured, with either baited cage traps or chemical immobilisation through darting. Darting proved to be a more efficient and less stressful way of capturing cats. Very high frequency (VHF) radio collars fitted with activity monitors were especially effective in the open habitat of the Kalahari for locating and maintaining contact with cats; they also aided in determining if the cats were active or resting in dense vegetation. The habituation of individual cats to a 4×4 vehicle proved to be time consuming, but it provided a unique opportunity to investigate the feeding ecology and spatial organisation of cats through direct visual observations. Conservation implications: In describing and comparing the various methods of capture, handling and release of the African wildcats that we followed during our study in the southern Kalahari, we recommend the most efficient, least stressful method for researchers to follow-both in relation to time and energy, as well as in terms of the impact on the animals being studied. © 2010. The Authors.Licensee.


Herbst M.,University of Pretoria | Herbst M.,Carnivore Conservation Group | Mills M.G.L.,University of Pretoria | Mills M.G.L.,Tony and Lisette Lewis Foundation
Journal of Zoology | Year: 2010

The seasonal feeding habits of the Southern African wildcat Felis silvestris cafra in the riverbed ecotone of the Kgalagadi Transfrontier Park were investigated over a period of 46 months. The diet was analysed through visual observations on eight habituated (three females and five males) radio-collared wildcats, supplemented with scat analysis. Murids formed the bulk of the biomass in the diet (73%), followed by birds (10%) and large mammals (>500 g) (9%). Although reptiles (6%) and invertebrates (2%) were frequently caught, they contributed less to the overall biomass of the diet. There were significant seasonal differences in the consumption of five food categories that related to changes in availability. Fluctuations in prey abundances could be the result of seasonal rainfall and temperature fluctuations or long-term variability in rainfall resulting in wet and dry cycles. As predicted, the lean season (hot-dry) was characterized by a high food-niche breadth and a high species richness. Despite sexual dimorphism in size in the Southern African wildcat, both sexes predominantly fed on smaller rodents, although there were differences in the diet composition, with males taking more large mammals and females favouring birds and reptiles. These results indicate that Southern African wildcats are adaptable predators that prefer to hunt small rodents, but can change their diet according to seasonal and longer-term prey abundances and availability. © 2010 The Authors. Journal compilation © 2010 The Zoological Society of London.

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