Conservação da andorinha-de-coleira, Pygochelidon melanoleuca (Wied, 1820) (Aves: Hirundinidae) no Brasil: ameaças por empreendimentos hidrelétricos

Abstract

The loss of habitat due to the construction of hydropower plants is the main threat related to the decline of the Black-collared Swallow population (Pygochelidon melanoleuca). We analyzed how much of its area of distribution is overlapped with the existing hydropower plants (current scenario) and planned (future scenario) in Brazil. We used the Random Forest, Maxent and Support Vector Machine algorithms to model the potential distribution of the species. Then, the model of potential distribution was overlapped with the location of existing and planned hydropower plants in order to calculate how much the potential area is and will be affected by the construction of these ventures. Approximately 35.33% of the built hydropower ventures are overlapped with the areas of potential distribution of the species. When we analyzed the superposition of the planned ventures, we verified that more 43.80% of the hydropower ventures will be overlapped with the area of potential distribution of the P. melanoleuca. Most hydropower plants located in the hydrographic regions of Paraná and Costa Atlântica Leste are in areas with less suitability of habitat for the occurrence of the species, and the ventures located in the hydrographic regions of Amazônica and Costa Atlântica Marajó are in areas with more suitability of habitat. The analyzes demonstrated that there was a reduction of quantity of suitable habitat for the species due to the superposition of hydropower ventures built in the areas of its potential distribution, and if the implementation of the planned ventures occurs, the quantity of necessary suitable habitat for the persistence of the species will continue to reduce.