Multiple-scale approach for evaluating the occupation of stingless bees in Atlantic forest patches

Abstract

Studies at multiple scales are essential to obtaining a holistic view of bee conservation. We aimed to detect the main factors that should be considered in a multiple-scale approach for small forest patches in order to contribute to the conservation plans for stingless bees. The study was conducted in small forest patches of the Atlantic Forest, in the municipality of Salto de Pirapora (SP, Brazil). The spatial analysis was developed based on forest patch size, forest patch core size, distance from the nearest forest patch, and distance from the nearest body of water. Based on these criteria, we selected three hotspot forest patches (including all criteria that favor the presence of stingless bees with arboreal nesting habits) and three control forest patches (which does not fulfill all these criteria), and we evaluated the presence of stingless bees based on the occupation of artificial shelters installed in the patches. From the 72 installed artificial shelters, we observed 27 shelters (37.5%) carrying some association with stingless bees presence. Bees showed a preference for occupying artificial shelters that were located in the patches’ cores (66.7%). The structure and composition of the vegetation showed great importance to the occupation of the artificial shelters, as there was a strong correlation between the occupied shelters and the diameter and the height of the trees. There was also a correlation between the presence of grasses and shrubs (p < 0.05), which were the main providers of floral resources. The data of the land cover was an essential factor for the development of spatial analysis, and we found a strong negative correlation with pastures and a positive correlation with forestry (p < 0.05). To elaborate multiscale approaches, it is essential to evaluate the quality of foraging (amount of flowers) and nesting (diameter and height of trees) resources, as well as the surroundings of the patches. The study provided data so that the information can be extrapolated to other scenarios and encourage the conservation of small forest patches as a strategy for the conservation of stingless bees.