Importance of connectivity for carnivore richness and occupancy in fragmented biodiversity hotspots
Cindy M. Hurtado, Gonçalo Curveira‐Santos, Álvaro García-Olaechea, Robyn D. Appleton, Cristian Barros‐Diaz, Txomin Hermosilla, Diego J. Lizcano, Jaime A. Salas, Diego Balbuena, Zoila Vega‐Guarderas, Ana Benítez‐López, Angela Brennan, A. Cole Burton
Abstract
Structural connectivity affects wildlife movement between habitat patches, contributing to the persistence of wildlife populations and their resilience to human-induced and environmental changes. However, its importance to wildlife population persistence remains unclear, particularly in fragmented landscapes, where there are additional co-occurring threats and varying protected area coverage (PAC). Using South American carnivore assemblages and fragmented tropical forests as a case study, we assessed the relative effect of structural connectivity on carnivore persistence in fragmented landscapes after accounting for PAC, and the efficacy of single-species connectivity approaches for protecting the habitat of multiple species. We applied a multiscale Bayesian modeling framework to camera-trapping data from 567 cameras in 23 landscapes in the Tumbesian region of Ecuador and Peru. We tested the landscape-scale effects of habitat amount, connectivity, human density, and protected area status on carnivore richness and mean occupancy and the fine-scale effects of forest cover, distance to roads, and hunting on carnivore site occupancy. In 41,861 camera days of sampling, we obtained 5267 independent detections of 12 carnivores across all landscapes. Connectivity, habitat amount, and PAC had a positive effect on carnivore richness, emphasizing that large and well-connected landscapes of natural habitat with greater PAC sustain more species-rich carnivore communities. Mean site occupancy across the carnivore community was positively associated with forest cover at the fine scale and connectivity at the landscape scale. This last relationship varied by species, with occupancy of forest-dependent mesocarnivores being most positively associated with higher connectivity. Our results highlight that increasing connectivity can improve the persistence of vulnerable carnivore populations, even in landscapes with varied amount of PAC. Furthermore, conservation planning to increase connectivity should take a multispecies approach because single-species approaches are unlikely to meet the needs of diverse communities.