Research on drivers of demographic rates has mostly focused on top predators and their prey, and comparatively less research has considered the drivers of mesopredator demography. Of those limited studies, most focused on top‐down effects of apex predators on mesopredator population dynamics, whereas studies investigating alternative mechanisms are less common. In this study, we tested hypotheses related to top‐down, bottom‐up and density‐dependent regulation of demographic rates in an imperilled mesopredator, the cheetah (Acinonyx jubatus). We used a 25‐year dataset of lion density, cheetah density and prey density from the Mun‐Ya‐Wana Conservancy in South Africa and assessed the effects of top‐down, bottom‐up and density‐dependent drivers on cheetah survival and reproduction. In contrast to the top‐down and bottom‐up predictions, both adult and juvenile cheetahs experienced the lowest survival during months with high prey densities and low lion densities. We observed support only for a density‐dependent response in juvenile cheetahs, where they had a higher probability of reaching independence during times with low cheetah density and low prey density. We did not identify any strong drivers of litter size. Collectively, our results indicate that high apex predator abundance might not always have negative effects on mesopredator populations, and suggest that context dependency in top‐down, bottom‐up and density‐dependent factors may regulate demographic rates of cheetahs and other mesopredators. Our results highlight the complexities of population‐level drivers of cheetah demographic rates and the importance of considering multiple hypotheses of mesopredator population regulation.

Expansion by expansive species can have severe ecological, social and economic impacts through the reduction of ecosystem goods and services and species richness. However, expansion by expansive species may also offer benefits to ecosystems and humans, through the supply of ecosystem goods and services (such as firewood, fodder and fruits), as well as potentially offering refugia in heavily used landscapes. Here, we examine the effects of four expansive dwarf shrub species (Aspalathus subtingens, Dicerothamnus rhinocerotis, Pteronia incana and Oedera genistifolia) on plant species richness (at the point scale), vegetation cover, soil properties and whether the expansive species offer refugia to other species. Plant species richness, cover and soil properties were recorded in 1‐m2 quadrats located within a mosaic of expanded and non‐expanded patches for the four expansive shrub species. Plant species richness was significantly higher in the non‐expanded areas compared to the expanded ones for all four expansive species. Some of the expansive shrubs provided refugia to certain plant species and limited the frequency of other species. With regard to species composition, there was little separation of expanded and non‐expanded samples within sites, indicating that the site factors were stronger determinants of plant species richness and composition than expansion. Therefore, it is more likely that the reduction in species richness in expanded sites is caused by multiple drivers, including vegetation attributes cover, litter cover and soil nutrients (organic C, Zn and P) and soil compaction. Copyright © 2017 John Wiley & Sons, Ltd.

Variability in habitat selection can lead to differences in fitness; however limited research exists on how habitat selection of mid-ranking predators can influence population-level processes in multi-predator systems. For mid-ranking, or mesopredators, differences in habitat use might have strong demographic effects because mesopredators need to simultaneously avoid apex predators and acquire prey. We studied spatially-explicit survival of cheetahs (Acinonyx jubatus) in the Mun-Ya-Wana Conservancy, South Africa, to test hypotheses related to spatial influences of predation risk, prey availability, and vegetation complexity, on mesopredator survival. For each monitored cheetah, we estimated lion encounter risk, prey density, and vegetation complexity within their home range, on short-term (seasonal) and long-term (lifetime) scales and estimated survival based on these covariates. Survival was lowest for adult cheetahs and cubs in areas with high vegetation complexity on both seasonal and lifetime scales. Additionally, cub survival was negatively related to the long-term risk of encountering a lion. We suggest that complex habitats are only beneficial to mesopredators when they are able to effectively find and hunt prey, and show that spatial drivers of survival for mesopredators can vary temporally. Collectively, our research illustrates that individual variation in mesopredator habitat use can scale-up and have population-level effects.

1. Fires are common in many ecosystems world-wide, and are frequently used as a management tool. Although the responses of herbivores to fire have been wellstudied, the responses of carnivores to fire remain unclear. In particular, post-fire habitat changes, and the associated changes in prey availability, might affect the coexistence or competition of carnivore species within the larger carnivore community, but few studies have focused on how fires influence multiple carnivore species simultaneously.2. Using South African carnivores as our focal community, we explored relative changes in carnivore intensity of use in post-fire landscapes associated with hypothesized changes in prey availability and top-down suppression.3. We monitored carnivore intensity of use in relation to prescribed burning using camera traps, with a Before-After-Control-Impact study design. We analysed the camera trap data using community N-mixture models to understand how individual species, as well as the carnivore guild as a whole, respond to burning. 4. Changes in carnivore intensity of use in response to prescribed burns were not uniform; however, no species decreased the intensity of use of post-fire landscapes. The apex predator, the lion Panthera leo, increased the use of prey-rich burnt areas, but other large carnivore species exhibited neutral responses to fire despite the associated prey increase. Responses of medium-and small-sized carnivores were species specific, and included both neutral and positive responses.Positive responses to fire by lions and herbivores were short-lived, and did not persist a year after burning occurred. Synthesis and applications.Our results indicate that fire does not promote carnivore coexistence by creating conditions for all carnivores to increase the use of burned areas, but that it also likely does not result in spatial avoidance of subordinate predators. Instead, fires might cause a suppression of opportunities for subordinate large carnivores because they need to avoid the apex predator, rather than take advantage of short-term increased hunting opportunities in recently burned areas. Our results highlight the complexity of understanding species-specific and community-level responses of carnivores to fire, and overlooked the ecological effects of its use as a management tool.

No abstract