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As the environment becomes increasingly altered by human development, the importance of understanding the ways in which wildlife interact with modified landscapes is becoming clear. Areas such as industrial sites are sometimes presumed to have little conservation value, but many of these sites have areas of less disturbed habitats around their core infrastructure, which could provide ideal conditions to support some species, such as mesocarnivores. We conducted the first assessments of the density of serval (Leptailurus serval) at the Secunda Synfuels Operations plant, South Africa. We ran three camera trap surveys to estimate serval density using a spatially explicit capture recapture framework. Servals occurred at densities of 76.20-101.21 animals per 100 km2, which are the highest recorded densities for this species, presumably due to high abundance of prey and the absence of persecution and/or competitor species. Our findings highlight the significant conservation potential of industrialised sites, and we suggest that such sites could help contribute towards meeting conservation goals.

Management zones feature prominently in conservation planning, particularly at large spatial scales, but prioritization of areas of concern is required to focus efforts and limited resources. Human-mediated mortality constitutes a major threat to species persistence, particularly for widespread carnivores that undergo harvest and population control, such as the leopard (Panthera pardus). In this study, we evaluated the extent and spatial distribution of legal anthropogenic offtake of leopards to identify de facto refugia and ecological traps across Limpopo Province, South Africa. We defined refugia as management units with offtake levels below an established sustainable harvest rate, and ecological traps as management units with offtake exceeding the sustainable harvest rate. We assessed offtake at three geographical scales using trophy hunting permit records alone, and then in combination with problem leopard permit records to investigate the compounding effect of additional forms of offtake and the potential for management scale mismatching. Across Limpopo Province, high leopard offtake created fewer areas of refuge than ecological traps. Refugia were smaller in size and within close proximity of ecological traps. Human-mediated leopard mortality occurred mostly in prime leopard habitat. Finer-scaled management units resulted in fewer ecological traps and more refugia, and enables authorities to focus conservation attention in areas of concern. Human-mediated leopard mortality exceeded the annual offtake rate considered sustainable. Our study highlights the importance of assessing both the scale and distribution of the harvest, whilst also considering alternative forms of offtake, when devising harvest management strategies. Management scale mismatching and high human-mediated leopard mortality is of particular concern in Limpopo Province, as such, we propose an adaptive, science-based regulatory framework aimed at improving leopard harvest strategies.

The ability to determine the prey-specific biomass intake of large predators is fundamental to their conservation. In the absence of actual prey data, researchers generally use a “unit mass” method (estimated as 3/4 adult female mass) to calculate the biomass intake of predators. However, differences in prey preference and range across geographic regions are likely to have an influence on biomass calculations. Here we investigate the influence of estimated prey mass on leopard biomass calculations, and subsequent carrying capacity estimates, in an understudied mountain population. Potential leopard feeding sites were identified using global positioning system (GPS) location clusters obtained from GPS collars. We investigated 200 potential leopard feeding sites, of which 96 were actual feeding sites. Jaw bones, horns, hooves, and other indicative bones were used to determine gender and age of prey items, which were subsequently used to calculate mass of each prey item based on previously published values. There were significant differences in the biomass values calculated using the traditional unit mass method and the calculated prey masses obtained from leopard feeding sites. However, there were no considerable differences in the carrying capacity estimates using the preferred prey species model and leopard density estimates calculated using a non-biased spatial approach, which suggests that estimating carnivore carrying capacity based on 3/4 adult female masses is a reliable method also for the mountain population in this study.