Conserving the Brazilian semiarid (Caatinga) biome under climate change

The Caatinga is a semiarid biome of the northeast of Brazil with only 1 % of its territory currently conserved. The biome's biodiversity is highly threatened due to exposure to land conversion for agricultural and cattle ranch. Climate forecasts predict increases in aridity, which could pose additional threats to the biome's biodiversity. Here, we ask if the remnants of natural vegetation in Caatinga biome, where endemic terrestrial vertebrate species occur, are likely to retain more climatic suitability under climate change scenarios than other less pristine areas of the biome. In order to assess changes in climate suitability across individual species ranges, ensemble forecasting was used based on seven bioclimatic envelope models, three atmosphere-ocean general circulation models, and two greenhouse emission gas scenarios for 2020, 2050, and 2080. We found that most species will gain climatic suitability in the natural vegetation remnants of the Caatinga. Such gains are even greater than the expected to occur within random sets of areas with size similar to the natural vegetation remnants. Our results suggest that natural vegetation remnants will likely play a role of climate refuges for endemic vertebrate species, so efforts should be concentrated in these regions.