Structure and inter-specific relationships of a felid community of the upper Amazonian basin under different scenarios of human impact

Human activities are changing ecosystems and their trophic structures across the globe and tropical forests are one of the main affected. Large carnivores can have a key role in the maintenance of biodiversity through direct and indirect effects at lower trophic levels, which are the result of predation and competition. In this sense, it is expected that changes in abundance of large predators driven by humans will affect the abundance of smaller carnivores. We explore the effects of varying degree of human intervention on the structure of a felid community of five sympatric species in Ecuador’s Amazon region. We used camera traps to survey carnivore populations in seven different areas between 2007 and 2016 and estimated density with spatial explicit capture–recapture models. The density of margays, jaguarundis, ocelots and jaguars showed a positive relationship with the conservation status of study sites, while no significant relationship was observed for pumas. We found that the anthropogenic impacts had asymmetric effects on the density of the different taxa. Jaguar and margays, the species with more stringent ecological requirements, presented higher reductions on density. Our findings support of the mesopredator release hypothesis in this tropical ecosystem. Maximum densities of pumas were detected in areas of low jaguar density, while there was a negative relationship between density of pumas and margays, jaguarundis, and ocelots. Our results show how human disturbance can have important ecological effects on the carnivore community. As felids are top predators, we can predict that changes in this trophic level can lead to changes in ecosystem function and structure. Therefore, conservation efforts should be addressed to maintain the structure of these communities.JMG. -S was supported by a Prometeo fellowship from the SENESCYT and the national agency for Education and Science of the Government of Ecuador.SE was supported by University of Florida, World Wildlife Fund Wildlife Conservation Society and Panthera to conduct research in Yasuní.Peer reviewe