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Context: Mesopredators experience top down pressure from apex predators, which may lead to behavioural changes such as spatial avoidance to reduce both interference and exploitative competition. However, apex predators may also facilitate mesopredators through the provision of carrion, so mesopredators should respond flexibly to the presence of apex predators. Aims: We aimed to investigate the drivers of black-backed jackal (Canis mesomelas) space use and detection in areas with and without lions (Panthera leo). We predicted that jackal detection and space use will be greater if apex predators facilitate rather than suppress them. Additionally, we predicted that in the absence of lions, the relative abundance of small ungulate species may become important drivers of space use and detection, because jackals can switch from scavenging to hunting. Comparatively, in the presence of lions, larger ungulate species will become important drivers of space use and detection as these species become accessible to jackals through scavenging. Methods: We used camera-trapping surveys, a single-species, single-season occupancy modelling approach, and the assessment of activity patterns to explore how apex predators influence the presence and probability of use of different sites in the Eastern Cape province of South Africa. Key results: Apex predators both positively and negatively affected the detection of jackals, indicating that these mesopredators show behavioural flexibility at the individual site level. There was high overlap between jackal activity patterns in the presence and absence of lions; however, at one site with lions, jackal activity did not peak at night as observed at other sites. Conclusions: Our results indicate that jackals demonstrate behavioural flexibility in the presence and absence of apex predators. Importantly, our results show that apex predators can both facilitate and suppress mesopredators, and that their behavioural responses are dependent on site-specific factors. Implications: Our findings highlight that sympatric predator behaviours should be based on site-specific behaviours instead of the general patterns observed in more temperate systems. We evaluated the influence of apex predators on the drivers of mesopredator space use and detection in South Africa. Apex predators both positively and negatively affected the detection of black-backed jackals, indicating that these mesopredators show behavioural flexibility at the individual site level. These findings suggest that sympatric predator behaviours should be based on site-specific behaviours instead of general patterns. Photograph by Rebecca Welch. [ABSTRACT FROM AUTHOR]

The Kruger National Park (KNP) is considered an important biodiversity hotspot, with insectivorous bats representing about twenty percent of the total mammalian diversity of South Africa. Historically, 40 bat species have been documented in the northern region of the Park between 1960 and 1990. However, it has been three decades since the last comprehensive assessment. To aid the long-term monitoring of bats within KNP, our study re-surveyed the bat community of northern KNP over two years, incorporated the latest acoustic technologies, compared changes in bat species richness with historical data, and tested the use of an automated classifier for the acoustic data. We captured bats and recorded echolocation calls at 26 sites), between March and October in 2017 and 2018. Kaleidoscope Pro software was used to identify each bat call series recorded. To enhance the accuracy of this tool, a northern KNP-specific classifier was developed. We recorded 27 distinct species during this study, of which 13 were live-captured. The historical data therefore show a much higher richness of bat species within the study area (40 species) than recorded during our study (27 species), although the former were collected over a much longer period of time during numerous collecting trips by staff of the former Transvaal Museum (Ditsong National Museum of Natural History). Total sample effort, environmental effects, biological aspects and overall study limitations likely contributed to the observed differences. The classifier tool had a relatively high percentage accuracy (80%) but manual identification was required to avoid the misidentification of rare species and to detect new species not previously recorded. Future studies should focus more effort on live-capturing, given the high species richness of the region and the limitation of bat detectors to record high frequency and low intensity echolocation calls, which are common in many southern African species. [ABSTRACT FROM AUTHOR]

Livestock guarding dogs (LGDs) have been used for centuries to reduce depredation on livestock and, more recently, to facilitate the conservation of threatened carnivores. Conservation organisations in southern Africa promote the use of Anatolian shepherds as LGDs. However, livestock farmers in Botswana use a variety of breeds for this purpose, including local landrace "Tswana" dogs. Our study sought to test the overall effectiveness of these local breeds as LGDs. Irrespective of breed, all LGDs reduced livestock losses, with 47.9% of farmers experiencing no losses after obtaining a guarding dog. Owners with more LGDs, and LGDs of a single sex, had greater reductions in livestock losses. Anatolian shepherds displayed more behavioural problems than other breeds in our study. The health of LGDs was reliant on them receiving a balanced diet, and owners with fewer dogs reported fewer health issues. Moreover, Tswana guarding dogs were cheaper to purchase and feed than their purebred counterparts. Our results show that local landrace dogs can be considered a cheaper and more practical alternative to purebred LGDs for reducing livestock losses and for mitigating human-wildlife conflict in Botswana. [ABSTRACT FROM AUTHOR]