Predicting the spatial distribution of four sympatric species of mid-sized carnivores in an Amazonian deforestation frontier

The 'arc of deforestation' of southern Amazonia has experienced one of the highest deforestation rates documented anywhere in the world and remaining forest patches are being rapidly converted into managed pastures. Understanding how forest and nonforest carnivores cope with habitat fragmentation in tropical agricultural frontiers and which species are more prone to extinction is an important tool for conservation planning. However, the secretive behaviour and low population densities of carnivores render data collection difficult. Thus, it is crucial to develop efficient analytical tools to interpret data for species distributions. Here, we use data from a long-term research program to determine the distribution of four sympatric mid-sized carnivore species and environmental factors related to their spatial distribution in a highly fragmented landscape using maximum entropy (MAXENT) modelling. MAXENT models-built from camera trapping, direct and indirect sighting records-indicate that land-cover, distance to water sources and distance from urban centres were the most important environmental variables of mid-sized carnivore species occurrence. In fact, land-cover and distance to water explained more than 80% for the occurrence of all four sympatric species in our study area. Higher probability of occurrences in areas closer to sources of water were especially important for Eira barbara and Leopardus pardalis, whereas areas closer to the urban centre showed lower probability of occurrences for Cerdocyon thous, E. barbara and L. pardalis. Of these carnivore species, C. thous was the only one that had higher probabilities of occurrence in non-forest areas. Thus, current levels of deforestation in the study region are likely to expand the distribution of C. thous but reduce the distribution of forest-dependent species such as L. pardalis and L. wiedii. This suggests that the region requires greater efforts in environmental law enforcement and education programmes to maintain the remaining forest cover and forest wildlife populations.