Low trophic niche overlap among trap-nesting bee species (Hymenoptera: Anthophila) in a semideciduous forest fragment

International audienceAbstractBees are important components of mutualistic interactions with plants, playing a key role as pollinators of both wild and crop plants. In this context, studies on the plants visited by bees are important to determining conservation strategies. We investigated the use of floral resources by the trap-nesting bee species sampled in a semideciduous forest fragment. Trap nests were set in the forest fragment in three different zones: forest edge, 250 m away from the edge and 500 m away from the forest edge. Pollen analysis of the residual pollen content removed from the nests of 12 bee species revealed a total of 63 pollen types from 16 botanical families. The bee community showed specialized populations with no overlap in diet. Within the community, the diet overlap was higher in closely related species, the two Tetrapedia species and the two Centris (Heterocentris) species, than in the other sampled species. Although the studied bee community is composed of widespread bee species, our data showed a low niche overlap among them, suggesting the occurrence of food niche partitioning at our study site. The asymmetry in the period of nesting activities and floral preferences among the bee species are factors that might have contributed to the low niche overlap observed