Integrating high-resolution remote sensing and empirical wildlife detection data for climate-resilient corridors across tropical elevational gradients

Abstract

Corridors are essential tools for promoting biodiversity resilience under climate change. However, corridor design studies are often conducted at spatial scales too coarse to guide implementation by local conservation practitioners. We mapped potential climate-resilient corridors linking lowland to highland protected areas within a highly biodiverse but fragmented landscape of southwestern Costa Rica (6311 km2) using least cost path and circuit theory approaches at high spatial resolution (10 m). We then applied an extensive camera trap dataset of medium-large vertebrates to examine corridor functionality. Although least cost paths (n = 40) were predominantly forested (median = 76 %, range = 57–82 %) and somewhat protected (median = 31 %, range = 3–55 %), they were also highly fragmented. Least cost paths from lowland to highland protected areas traversed medians of 252 forest patches (range = 162–328), 11,186 agriculture patches (range = 822–1,771), and 106 roads (range = 50–252), translating to 2 forest patches, 11 agriculture patches, and 1 road crossed every kilometer. Circuit analyses identified many high-connectivity areas outside of protected areas, including but not limited to least cost paths, but these high-connectivity areas were mostly small forest fragments. Nonetheless, capture rates for medium-to-large mammals at camera traps indicated that many species are currently unlikely to use unprotected, fragmented areas thought to be important for connectivity. In other words, additional conservation and restoration are necessary to establish functional corridors within the landscape. More broadly, this study exemplifies an approach to bridging the gap between regional-scale connectivity analyses and the needs of local practitioners by identifying locations that could be targeted for conservation or restoration within multi-use tropical landscapes.