Modelagem de nicho ecológico e conservação de aves ao longo de um gradiente altitudinal: impactos das mudanças climáticas futuras

Abstract

The Atlantic Forest is one of the most biodiverse ecosystems in the world and, despite being a conservation priority, only about 28% of its original coverage remains, mainly in isolated fragments. However, large blocks of vegetation still exist, especially in the mountainous regions of southeastern Brazil. On a global scale, mountains house a third of terrestrial biodiversity but are also highly vulnerable to climate change, which particularly affects montane birds due to their high habitat specialization. This study aims to map habitat suitability for fourteen species of endemic birds from high-altitude regions of the Southern and Southeastern Atlantic Forest, analyzing variations in suitability between the present scenario and future climate change scenarios, based on the SSP3-7.0 scenario for the 2081-2100 period. Additionally, it evaluates the effectiveness of Protected Areas (PAs) in the conservation of these species. To this end, fourteen species of endemic birds were selected, and using bioclimatic variables and topographic predictors, their ecological niches were modeled with the Maxent and Random Forest algorithms in RStudio. The accuracy of the models was assessed using AUC (Area Under the ROC Curve) and TSS (True Skill Statistic) indices, generating consensus models for each species. Environmental suitability maps were produced in QGIS to quantify areas of suitable habitat. The effectiveness of PAs was analyzed based on variations in the protected area occupied by the species and the identification of conservation gaps. The results indicate a significant reduction in habitat for nine of the fourteen species analyzed, with an average loss of 46,28%. Regarding the effectiveness of PAs, the analysis revealed that most taxa will experience a reduction in suitability within Conservation Units, being classified as "Partially Protected" in both the current and future scenarios. These results emphasize the importance of adaptive management strategies and the urgent need for public policies aimed at expanding and improving PAs, to mitigate the impacts of climate change on the biodiversity of montane birds in the Southern and Southeastern Atlantic Forest and ensure their long-term persistence.