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Theory on intraguild killing (IGK) is central to mammalian carnivore community ecology and top-down ecosystem regulation. Yet, the cryptic nature of IGK hinders empirical evaluations. Using a novel data source - online photographs of interspecific aggression between African carnivores - we revisited existing predictions about the extent and drivers of IGK. Compared with seminal reviews, our constructed IGK network yielded 10 more species and nearly twice as many interactions. The extent of interactions increased 37% when considering intraguild aggression (direct attack) as a precursor of killing events. We show that IGK occurs over a wider range of body-mass ratios than predicted by standing competition-based views, with highly asymmetrical interactions being pervasive. Evidence that large species, particularly hypercarnivore felids, target sympatric carnivores with a wide range of body sizes suggests that current IGK theory is incomplete, underestimating alternative competition pathways and the role of predatory and incidental killing. Our findings reinforce the potential for IGK-mediated cascades in species-rich assemblages and community-wide suppressive effects of large carnivores.

Simple Summary Wildlife ecological patterns are driven not only by environmental and biological contexts, but also by landscape-management schemes that shape those contexts. The present study aims to determine the effect of different environmental factors (including management schemes) on the occurrence patterns of a southern African small mammal community. Based on a landscape where three land-use contexts that differ in their levels of human presence and/or where activities coexist (private ecotourism reserve, mixed farms and traditional communal areas), and by using a body-size-based approach (i.e., using two size-based rodent groups—medium and small—as models), we found that the mean relative abundance of medium-sized species did not differ across the management contexts, but small species’ mean relative abundance was higher in the game reserve. The overall variation in rodent abundance was negatively affected by ungulate presence (possibly linked to a decrease in food availability) and by human presence (increased disturbance). Rodent abundance seems to be influenced by environmental gradients that are directly linked to varying management priorities across land uses, meaning that these communities might not benefit uniformly by the increased amount of habitat promoted by the commercial wildlife industry. Abstract South Africa’s decentralized approach to conservation entails that wildlife outside formally protected areas inhabit complex multi-use landscapes, where private wildlife business (ecotourism and/or hunting) co-exist in a human-dominated landscape matrix. Under decentralized conservation, wildlife is perceived to benefit from increased amount of available habitat, however it is crucial to understand how distinct management priorities and associated landscape modifications impact noncharismatic taxa, such as small mammals. We conducted extensive ink-tracking-tunnel surveys to estimate heterogeneity in rodent distribution and investigate the effect of different environmental factors on abundance patterns of two size-based rodent groups (small- and medium-sized species), across three adjacent management contexts in NE KwaZulu-Natal, South Africa: a private ecotourism game reserve, mixed farms and traditional communal areas (consisting of small clusters of houses interspersed with grazing areas and seminatural vegetation). Our hypotheses were formulated regarding the (1) area typology, (2) vegetation structure, (3) ungulate pressure and (4) human disturbance. Using a boosted-regression-tree approach, we found considerable differences between rodent groups’ abundance and distribution, and the underlying environmental factors. The mean relative abundance of medium-sized species did not differ across the three management contexts, but small species mean relative abundance was higher in the game reserves, confirming an influence of the area typology on their abundance. Variation in rodent relative abundance was negatively correlated with human disturbance and ungulate presence. Rodent abundance seems to be influenced by environmental gradients that are directly linked to varying management priorities across land uses, meaning that these communities might not benefit uniformly by the increased amount of habitat promoted by the commercial wildlife industry.

This work was supported by the Peace Parks Foundation; G.C.S. was funded by a doctoral grant from Fundacão para a Ciência e a Tecnologia (FCT: PD/BD/114037/2015); L.H.S. was supported by the National Research Foundation, South Africa (UID: 107099 and 115040) and by the African Institute for Conservation Ecology. Apex predator reintroductions have proliferated across southern Africa, yet their ecological effects and proposed umbrella benefits of associated management lack empirical evaluations. Despite a rich theory on top-down ecosystem regulation via mesopredator suppression, a knowledge gap exists relating to the influence of lions (Panthera leo) over Africa's diverse mesocarnivore (less than 20 kg) communities. We investigate how geographical variation in mesocarnivore community richness and occupancy across South African reserves is associated with the presence of lions. An interesting duality emerged: lion reserves held more mesocarnivore-rich communities, yet mesocarnivore occupancy rates and evenness-weighted diversity were lower in the presence of lions. Human population density in the reserve surroundings had a similarly ubiquitous negative effect on mesocarnivore occupancy. The positive association between species richness and lion presence corroborated the umbrella species concept but translated into small differences in community size. Distributional contractions of mesocarnivore species within lion reserves, and potentially corresponding numerical reductions, suggest within-community mesopredator suppression by lions, probably as a result of lethal encounters and responses to a landscape of fear. Our findings offer empirical support for the theoretical understanding of processes underpinning carnivore community assembly and are of conservation relevance under current large-predator orientated management and conservation paradigms. Postprint

The growing needs for agricultural expansion and intensification will likely continue to reduce and fragment the terrestrial habitats fundamental to mammalian carnivores. Recent research identified benefits of agroecosystems to carnivores recognizing their multifunctionality, mostly for common species. However, the variability of carnivore ecology investigated in agroecosystems, biases in agriculture types and species targeted, and methodological approaches may affect the available knowledge to reconcile conservation and agricultural production. To fill this gap, we conducted a systematic literature review to identify which aspects of and how is carnivore spatial ecology being investigated within agroecosystems. Of the 110 reviewed studies, most focused on agricultural crops (55%) and grasslands (47%) and half referred to monocultures. We found that 61% of the studies were conducted in Europe and North America. Eighty-four carnivore species were studied, 73% classified as Least Concern, with 67% of the studies targeting a single species and 30% focused on only seven common species. Almost all studies included some form of habitat use analysis and species’ home-range and its attributes (e.g. size, resource selection), the most common spatial ecology aspects studied. Most studies suggested that agriculture functions as food provisioning (69%) but few used direct food availability measures. Our results highlight that studies tend to be descriptive and geographically biased towards northern hemisphere and to non-forested agricultural types. We suggest that future carnivore spatial ecology research in agroecosystem should be hypotheses-driven, with greater focus on the mechanisms and processes through which agroecosystems might affect carnivore spatial ecology in particular for areas with high priority for carnivore conservation.

Funding: African Institute for Conservation Ecology; Fundação para a Ciência e a Tecnologia. Grant Numbers: PD/BD/114037/2015, UID/BIA/00329/2019; National Geographic Society. Grant Number: EC-314R-18; Wild Tomorrow Fund; South African Agency for Science and Technology Advancement. Grant Number: UID: 107099&115040. 1 Conservation efforts in South Africa play out across multi-use landscapes where formal protected areas coexist with private wildlife business (ecotourism and/or hunting) in a human-dominated matrix. Despite the persistence of highly diverse carnivore guilds, management idiosyncrasies are often orientated towards charismatic large predators and assemblage-level patterns remain largely unexplored. 2. We conducted an extensive camera-trap survey in a natural quasi-experimental setting in KwaZulu-Natal, South Africa. We sampled across a protection gradient characterized by a provincial protected area (highest and formal protection status), a private ecotourism reserve, game ranches and traditional communal areas (lowest protected status). We evaluated assemblage-level and species-specific responses of free-ranging carnivores to the varying management contexts and associated environmental gradients. 3. Despite similar assemblage composition between management contexts, site-scale carnivore richness and occupancy rates were greater in the formal protected area than adjacent private reserve and game ranches. Carnivore occupancy was more similar between these private wildlife areas, although putative problem species were more common in the private reserve, and contrasted with depauperate assemblages in least protected communal lands. Variation in carnivore occupancy probabilities was largely driven by land use contexts, that is, the level and nature of protection, relative to underlying fine-scale landscape attributes (e.g. distance to conservation fences) or apex predator populations. 4. Synthesis and applications. Our findings provide convincing empirical support for the added value of multi-tenure conservation estates augmenting and connecting South Africa's protected areas. However, our emphasis on free-ranging carnivores exemplifies the importance of maintaining areas under long-term formal protection and the risks with viewing lucrative wildlife business as a conservation panacea. We suggest that unmanaged carnivore species be the formal components of carnivore reintroduction and recovery programmes to better gauge the complementary conservation role of South Africa's private land. Postprint

This study was conducted at a research and monitoring station of the LTsER Montado platform (http://www.ltsermontado.pt/) through a research protocol established between Companhia das Lezírias S.A. (CL) and Faculdade de Ciências da Universidade de Lisboa (FCUL), under the strategic plan of the Centre for Ecology, Evolution and Environmental Changes (cE3c) and with the support of the Foundation for Science and Technology (FCT, UID/BIA/00329/2019). T.A.M. thanks partial support by CEAUL (funded by FCT through the project UID/MAT/00006/2019). G.C.S. was funded by a doctoral grant from FCT (PD/BD/114037/2015). The patterns of species co-occurrence have long served as a primary approach to explore concepts of interspecific interaction. However, the interpretation of such patterns is difficult as they can result from several complex ecological processes, in a scale-dependent manner. Here, we aim to investigate the co-occurrence pattern between European rabbit and wild boar in an estate in Central Portugal, using two-species occupancy modelling. With this framework, we tested species interaction for occupancy and detection, but also the interdependencies between both parameters. According to our results, the wild boar and European rabbit occurred independently in the study area. However, model averaging of the detection parameters revealed a potential positive effect of wild boar’s presence on rabbit’s detection probability. Upon further analysis of the parameter interdependencies, our results suggested that failing to account for a positive effect on rabbit’s detection could lead to potentially biased interpretations of the co-occurrence pattern. Our study, in spite of preliminary, highlights the need to understand these different pathways of species interaction to avoid erroneous inferences. Publisher PDF

Aim: In the light of human-induced rapid environmental change (HIREC), populations are exposed to ever-greater bioclimatic stress at the edge of a species’ historic range. The distribution dynamics of European badgers (Meles meles) at their southern edge are linked tightly to climatic variability. We contribute critical data on how climatic context and local factors determine site occupancy in a northern-range population. Location: Eleven study areas (averaging ~21.3 km 2 ) spread over ~50,000 km 2 in Northern Scotland. Methods: While accounting for heterogeneous detectability, we applied single-season occupancy models to broad-scale camera-trapping data (168 stations) to evaluate how Autumn–Winter weather conditions interact with land-cover type (including agricultural land) and human disturbance to determine badger occupancy. Results: Mean minimum daily winter temperature and elevation influenced inter-site occupancy. When clustering study areas into two distinct topo-climatic types, badger occupancy was associated with agriculture in areas with lower mean minimum winter temperatures ( < 0.3°C) at higher elevation ( > 246 m). In areas with higher mean minimum winter temperature ( > 1.2°C) at lower elevation ( < 133 m), badgers selected sites further away from human infrastructures (settlements and main roads). Climatic factors and human disturbance interact in intricate, context-dependent patterns to determine badger site occupancy. Main Conclusions: The UKCP09 Medium Emissions Scenario projects a winter mean minimum temperature increase of between 1 and 3°C (central estimate) for Northern Scotland by the 2050s. Although warmer weather should benefit badger occupancy, this may be counteracted by up to a predicted 5% human population increase in the Scottish highlands, by 2037, which is likely to disturb badgers. We show that even in instances where species’ regional responses to climate change are positive, these effects can be neutralized by other anthropogenic pressures. Our findings add to the growing body of evidence advocating that interactive effects should be taken into account when planning conservation management.

During the final stage of the study GCS was funded by a doctoral grant from FCT (PD/BD/114037/2015). TAM thanks support by CEAUL (funded by FCT project – UID/MAT/00006/2013). In the multi-functional and biodiverse cork oak landscapes of Iberia (Montado), agro-silvo-pastoral practices promote landscape heterogeneity and create intricate habitat and resource availability patterns. We used camera-traps to investigate the temporal and spatial organisation of a mesocarnivore community in a Montado landscape in central Portugal. The target carnivore assemblage was largely dominated by three generalist species – the red fox Vulpes vulpes, the European badger Meles meles and the Egyptian mongoose Herpestes ichneumon – while remaining community members – the common genet Genetta genetta and the feral cat Felis silvestris spp. – exhibited restricted distributions. Interspecific differences in activity rhythms and habitat use were particularly marked among widespread species. Low temporal overlap was reported between the diurnal mongoose and predominantly nocturnal red fox and badger. For the latter two species, contrasting differences in habitat use were associated with anthropogenic-induced environmental heterogeneity. Whereas the red fox used more intensively Montado areas preserving dense shrubby understory and avoided semi-disturbed mosaics of sparse shrubs, the badgers displayed the opposite pattern. Our findings add to previous evidence suggesting that the spatial structure created in highly managed landscapes, particularly the diversity of resulting understory structures, promotes the abundance and spread of generalist mesocarnivore species. These may benefit from the surplus of resource amount (e.g. prey) and the creation of different human-made habitats conditions that provide particular combinations of ecological resources favourable to each species requirements. We concur the common view that maintaining understory heterogeneity in Montado landscapes, menaced by current intensification and extensification trends, is important where carnivore persistence is a relevant conservation goal, but alert for potential effects on carnivore assemblages structuring and impacts for specialist species less tolerant to disturbance. Postprint