The bee community (Hymenoptera, Apidae) of Ilha Grande, Babitonga bay, Santa Catarina State, Brazil: structure, insularity and interaction network

Island biotic communities tend to be less diverse than mainland communities. This work aimed to describe the bee community of Ilha Grande, Babitonga Bay, Santa Catarina, Brazil, and its interactions with floral resources. Entomological net-sweeps were used to collect bees in flight or on flowering plants for 7 hours a day, monthly, for two years. A total of 785 specimens were sampled in the field, belonging to 50 species or morphotypes with four indeterminate individuals. The most representative subfamilies were Apinae (58.59%), Halictinae (40.43%), Colletinae (0.8%) and Megachilinae (0.1%), while the most abundant species were Apis mellifera (305 individuals), Dialictus sp. 1 (182) and Dialictus sp. 2 (32). The presence of Apis mellifera decreased diversity throughout the year. Relative abundance and richness of Halictinae were greater on the island on mainland. Richness of Apinae was lower on the island than that on the mainland due to the absence of Meliponina. A total of 55 botanical species were identified in association with bees, with Schinus terebinthifolius (105 visits) being the most visited. Interaction network metrics indicate an asymmetric, nested, and poorly specialized network. The results corroborate the Theory of Island Biogeography and demonstrate little interference/favoring of some taxa as well as the absence of others.