Browsing by Author "Drouilly, Marine"

Now showing 1 - 4 of 4
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    A brief history of predators, sheep farmers and government in the Western Cape, South Africa
    (2017-03) Nattrass, Nicoli; Conradie, Beatrice; Drouilly, Marine; O'Riain, M. Justin
    This paper provides a brief history of the conflict between South African sheep farmers and predators (and we touch also on the debate between diverse stakeholders over how best to respond to that conflict). We focus in particular on black-backed jackals and commercial sheep farmers in the Western Cape Karoo, drawing on historical sources, colonial records, early ecological thinking and observations by farmers to paint a picture of this dynamic conflict. The paper forms part of an inter-disciplinary project about sheep farming and predators in the Karoo
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    Investigating the hidden costs of livestock guarding dogs and the diet of a sympatric predator in Namaqualand, South Africa
    (2018) Kelly, Caitlin; O'riain, Justin; Drouilly, Marine
    The global decimation of carnivore populations has been called one of mankind’s most pervasive impacts on the natural world. Human-wildlife conflict over the threat (both real and perceived) predators pose to livestock is one of the leading causes of carnivore decline worldwide. Livestock guarding dogs have been widely acclaimed as an environmentally friendly tool for reducing this conflict, yet little is known about the hidden costs of their presence. This study used scat analysis to reconstruct the diet of livestock guarding dogs and local caracals (Caracal caracal) to better understand their impacts on biodiversity and livestock in Namaqualand, South Africa. For livestock guarding dogs, 187 scats revealed the consumption of (from most to least frequent): livestock, wild mammals (including ten native species), vegetation, anthropogenic items, invertebrates, reptiles, fruit and birds. However, the diet of dogs accompanied by a human attendant differed significantly (χ 2 = 94.075, p < 0.001) from dogs guarding sheep independently. While 75% of scats collected from dogs operating independently contained domestic ungulates, less than 5% of scats from dogs with a human attendant contained livestock. For caracals, 185 collected scats were analysed across two land uses: Namaqua National Park and surrounding farms. Eighteen mammalian prey species were identified in their overall diet, with medium sized (1-10 kg) mammals (particularly the rock hyrax, Procavia capensis) accounting for more than half of consumed prey (59.1%). Small mammals (<1 kg) and wild ungulates were consumed more frequently in the protected area than on farmland. Livestock comprised 16% of the mammalian biomass consumed on farms, however no livestock was found in caracal scat within the protected area. These results support a growing body of research that suggests caracals do not prefer livestock, but will consume them when their numbers are considerably higher than that of wild prey, as is the case on many farms. Although this analysis cannot differentiate between predation and scavenging, the results provide novel insight into the potential impacts of livestock guarding dogs on the landscape and their overall effectiveness as a nonlethal predator management tool. This can help inform livestock guarding dog training and predator management while providing key information about the diets of both an indigenous and introduced predator.
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    Molecular detection of tick-borne pathogens in caracals (Caracal caracal) living in human-modified landscapes of South Africa
    (2020-04-30) Viljoen, Storme; O’Riain, M J; Penzhorn, Barend L; Drouilly, Marine; Serieys, Laurel E K; Cristescu, Bogdan; Teichman, Kristine J; Bishop, Jacqueline M
    Background Wild carnivores living alongside humans and domestic animals are vulnerable to changes in the infectious disease dynamics in their populations. The aims of this study were to determine the prevalence and diversity of selected tick-borne pathogens (TBPs) of veterinary and/or zoonotic concern in wild populations of caracals (Caracal caracal) occurring in human-modified landscapes in South Africa. Using molecular techniques, we screened 57 caracal blood samples for infection by rickettsial bacteria and piroplasms in three regions of South Africa: rangeland in the Central Karoo (n = 27) and Namaqualand (n = 14) as well as the urban edge of the Cape Peninsula (n = 16) of South Africa. To characterise pathogen identity, we sequenced the 18S rRNA and 16S rRNA genes from positive samples and analysed sequences within a phylogenetic framework. We also examine the diversity of potential tick vectors. Results All individuals tested were infected with at least one tick-borne pathogen. Pathogens included Hepatozoon felis, Babesia felis, Babesia leo and a potentially novel Babesia species. An Anaplasma species previously described in South African domestic dogs was also found in 88% of urban edge caracals. Higher rates of co-infection characterised urban edge caracals (81% vs 15% and 0% in the two rangeland populations), as well as a greater incidence of mixed infections. Host attached tick species include Haemaphysalis elliptica, an important pathogen vector among carnivore hosts. Conclusions This study confirms the occurrence of previously undocumented tick-borne pathogens infecting free-ranging caracals in human-modified landscapes. We identify clear differences in the pathogen profiles among our study populations and discuss the likely health costs to caracals living adjacent to urban areas.
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    Understanding the black-backed jackal
    (2017-03) Nattrass, Nicoli; Conradie, Beatrice; Drouilly, Marine; O'Riain, M Justin
    This paper reviews what we know about black-backed jackal ecology, drawing implications for managing human-wildlife conflict with this species. We review the research literature on the black-backed jackals in the context of other African jackal species and with regard to its diet (part 1), its breeding, territoriality and sociality (part 2), and its role as a ‘problem animal’ for small stock farmers (part 3). We argue that both the historical record (see also Nattrass et al., 2017) and the scientific research points to the need to understand the black-backed jackal as a very adaptable animal whose diet, breeding strategies and social arrangements are context-dependent. We draw implications for the management of black-backed jackal predation (part 4) and need for further research, especially on farmlands and landscapes undergoing a transformation in land use. The paper is part of an inter-disciplinary project about sheep farming and predators in the Karoo.