Macroscale climate change predictions have little influence on landscape-scale habitat suitability

Abstract

Although a few studies have addressed the combined effects of climate change and habitat loss on biodiversity at a regional scale, the extent to which climate change will impact species occurrence at the landscape scale remains unclear. We evaluated the potential effects of climate change at the landscape scale for 11 bird species endemic to the Atlantic Forest biodiversity hotspot. We quantified current and future climatic suitability for each species using ecological niche models, and quantified habitat amount and structure using connectivity analyses. Climate and landscape suitability were then combined using two approaches, which differed in the spatial scale at which climate was quantified. First, we incorporated climate at patch-level into the probability of connectivity (PC) index, obtaining a Combined Landscape Suitability (CLS) index. Second, we multiplied climate at landscape-level with PC. Climatic suitability at the landscape scale was predicted to vary little (<3%) from current to future conditions and there was a high correlation between current and future CLS and PC x climate, regardless of the method used and species’ trait differences (r ≥ 0.95 for all species). Landscapes that currently have the highest suitability for birds are likely to remain highly suitable in the future, regardless of climate change. For Atlantic Forest endemic birds, our results suggest that climate change will have minor effects on landscape-level, which does not exclude potential impacts at a regional scale. This study supports the growing perception that, in tropical regions, land-use change is an urgent threat to biodiversity.