The wide-ranging, cumulative, negative effects of anthropogenic disturbance, including habitat degradation, exotic species, and hunting, on native wildlife has been well documented across a range of habitats worldwide with carnivores potentially being the most vulnerable due to their more extinction prone characteristics. Investigating the effects of anthropogenic pressures on sympatric carnivores is needed to improve our ability to develop targeted, effective management plans for carnivore conservation worldwide. Utilizing photographic, line-transect, and habitat sampling, as well as landscape analyses and village-based bushmeat hunting surveys, we provide the first investigation of how multiple forms of habitat degradation (fragmentation, exotic carnivores, human encroachment, and hunting) affect carnivore occupancy across Madagascar’s largest protected area: the Masoala-Makira landscape. We found that as degradation increased, native carnivore occupancy and encounter rates decreased while exotic carnivore occupancy and encounter rates increased. Feral cats (Felis species) and domestic dogs (Canis familiaris) had higher occupancy than half of the native carnivore species across Madagascar’s largest protected landscape. Bird and small mammal encounter rates were negatively associated with exotic carnivore occupancy, but positively associated with the occupancy of four native carnivore species. Spotted fanaloka (Fossa fossana) occupancy was constrained by the presence of exotic feral cats and exotic small Indian civet (Viverricula indica). Hunting was intense across the four study sites where hunting was studied, with the highest rates for the small Indian civet ( individuals consumed/year), the ring-tailed vontsira (Galidia elegans) ( consumed/year), and the fosa (Cryptoprocta ferox) ( consumed/year). Our modeling results suggest hunters target intact forest where carnivore occupancy, abundance, and species richness, are highest. These various anthropogenic pressures and their effects on carnivore populations, especially increases in exotic carnivores and hunting, have wide-ranging, global implications and demand effective management plans to target the influx of exotic carnivores and unsustainable hunting that is affecting carnivore populations across Madagascar and worldwide.

Madagascar's Eupleridae carnivores are perhaps the least studied and most threatened family of Carnivora. Investigating potential direct and indirect competition among these native species and sympatric exotic carnivores is necessary to better direct conservation actions. From 2008 to 2013, we photographically surveyed a diverse rainforest landscape, comparing six native and three exotic carnivores' activity patterns throughout the diel cycle. We used hierarchical Bayesian Poisson analysis to describe the activity patterns of Madagascar's carnivore community, assessed effects of season and site on temporal activity patterns, and estimated coefficients of overlap between carnivore pairings to assess effects of body size and ecological niche on temporal overlap among native and exotic carnivores. We observed changes in temporal activity patterns across seasons particularly during the austral summer (hot-dry season) for four native and two exotic carnivores, including evidence of fossa Cryptoprocta ferox altering their temporal activity during their mating season (hot-dry season). We found evidence of high overlap between natives and exotics indicating the potential for increased interactions and competition. The greatest overlap in temporal activity occurred between both ring-tail Galidia elegans and brown-tail vontsira Salanoia concolor and exotic dogs Canis familiaris. Cr. ferox, falanouc Eupleres goudotii and spotted fanaloka Fossa fossana also overlapped in activity with the nocturnal, exotic Indian civet Viverricula indica. Cr. ferox avoided humans and Ca. familiaris across all seasons. Unexpectedly, carnivore body size and ecological niche were not important predictors of temporal overlap. Previous research has shown these native and exotic carnivores overlap spatially and these new findings of temporal overlap among native and exotic carnivores add urgency to the need to manage exotic carnivores across Madagascar.

The composition of local mammalian carnivore communities has far-reaching effects on terrestrial ecosystems worldwide. To better understand how carnivore communities are structured, we analysed camera trap data for 108 087 trap days across 12 countries spanning five continents. We estimate local probabilities of co-occurrence among 768 species pairs from the order Carnivora and evaluate how shared ecological traits correlate with probabilities of co-occurrence. Within individual study areas, species pairs co-occurred more frequently than expected at random. Co-occurrence probabilities were greatest for species pairs that shared ecological traits including similar body size, temporal activity pattern and diet. However, co-occurrence decreased as compared to other species pairs when the pair included a large-bodied carnivore. Our results suggest that a combination of shared traits and top-down regulation by large carnivores shape local carnivore communities globally.

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1. Perceived predation risk and the resulting antipredator behaviour varies across space, time and predator identity. Communities with multiple predators that interact and differ in their use of space, time of activity and hunting mode create a complex landscape for prey to avoid predation. Anthropogenic presence and disturbance have the potential to shift interactions among predators and prey and the where and when encounters occur.2. We examined how white-tailed deer Odocoileus virginianus fawn spatiotemporal antipredator behaviour differed along an anthropogenic disturbance gradient that had black bears Ursus americanus, coyotes Canis latrans, bobcats Lynx rufus and humans present.3. We quantified (a) spatial co-occurrence in species distributions, (b) temporal overlap across the diel cycle and (c) spatiotemporal associations between humans, bears, coyotes, bobcats, adult male deer and fawns. We also examined how deer vigilance behaviour changed across the anthropogenic disturbance gradient and survey duration. Anthropogenic disturbance influenced spatiotemporal co-occurrence across multiplescales, often increasing spatiotemporal overlap among species. In general, species' spatial co-occurrence was neutral or positive in anthropogenically disturbed environments. Bears and fawns, coyotes and adult male deer, and bobcats and fawns all had higher temporal overlap in the agriculture-development matrix sites. In addition, factors that influenced deer vigilance (e.g. distance to forest edge and predator relative abundance) in the agriculture-development matrix sites did not in the forest matrix site. 5. By taking into account the different antipredator behaviours that can be detected and the different scales these behaviours might occur, we were able to gain a more comprehensive picture of how humans reduce available niche space for wildlife, creating the neutral and positive spatiotemporal associations between species that studies have been seeing in more disturbed areas.