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bioRxiv · 10.1101/2020.11.02.364638

Density responses of lesser-studied carnivores to habitat and management strategies in southern Tanzanias Ruaha-Rungwa landscape

Hardouin, M.·Searle, C. E.·Strampelli, P.·Smit, J.·Dickman, A.·Lobora, A. L.·Rowcliffe, J. M.
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Abstract

Compared to emblematic large carnivores, less charismatic or smaller carnivore species often receive little conservation attention, despite facing increasing anthropogenic pressure, and their status being poorly understood across much of their range. We employed systematic camera trapping and spatially explicit capture-recapture modelling to estimate variation in population density of serval, striped hyaena and aardwolf across the mixed-use Ruaha-Rungwa landscape in southern Tanzania. Three sites were selected as representative of different habitat types, management strategies, and levels of anthropogenic pressure: Ruaha National Parks core tourist area, dominated by Acacia-Commiphora bushlands and thickets; the Parks miombo woodland; and the neighbouring community-run MBOMIPA Wildlife Management Area, also covered in Acacia-Commiphora. Our results show that the Parks miombo woodlands supported a higher serval density than the core tourist area and Wildlife Management Area, with 5.56 [Standard Error = {+/-}2.45], 3.45 [{+/-}1.04] and 2.08 [{+/-}0.74] individuals per 100 km2, respectively. This variation is likely driven by precipitation, the abundance of apex predators, and the level of anthropogenic pressure. Striped hyaena were detected only in the Wildlife Management Area and at low density (1.36 [{+/-}0.5] individuals per 100 km2), potentially due to the location of the surveyed sites at the edge of the species global range, high densities of sympatric competitors and anthropogenic edge effects. Finally, aardwolf were captured in both the Parks core tourist area and the Wildlife Management Area, with a higher density in the Wildlife Management Area (13.25 [{+/-}2.48] versus 9.19 [{+/-}1.66] individuals per 100 km2), possibly as a result of lower intraguild predation and late fire outbreaks in the area surveyed. By shedding light on three understudied African carnivore species, this study highlights the importance of miombo woodland conservation and community-managed conservation, as well as the value of camera trap data to improve ecological knowledge of lesser-studied carnivores.

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Hardouin, M., Searle, C. E., Strampelli, P., Smit, J., Dickman, A., Lobora, A. L., Rowcliffe, J. M.. 2020-11-02. Density responses of lesser-studied carnivores to habitat and management strategies in southern Tanzanias Ruaha-Rungwa landscape. https://doi.org/10.1101/2020.11.02.364638

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