Urbanization Affects the Occurrence of a Large Stingless Bee Species in a Large City

Abstract Insightful studies of habitat fragmentation and bees will consider fragmentation, alteration, and loss of nesting habitats, not just patches of forage plants, as well as the permeability of the surrounding matrix to interpatch movement. Most previous studies on bees defined habitat fragments as remnant patches of floral hosts or forests, overlooking the nesting needs of bees, with their conclusions being that habitat fragmentation is broadly deleterious, but there still remain contrasting results in the literature. We investigated the effects of fragmentation, caused by urbanization, and the permeability of the surrounding matrix on the occurrence of one species of large-sized stingless bee. Individuals of Melipona quadrifasciata were collected at flowering plants in 11 Atlantic Forest fragments (ranging 64–1,406 ha) in southeastern Brazil and analyzed the vegetation structure of the fragments and classified the urbanized matrix. We examined the effects of forest fragment size, fragment isolation and the urban landscape context on the occurrence of M. quadrifasciata. We found the species to be highly dependent on large and tall trees and was found in large fragments with high tree species richness and tree density. The urbanized landscape context was also found to be directly related to the presence of M. quadrifasciata, with the species’ absence from fragments in a highly urbanized landscape. We conclude that habitat quality within a fragment (vegetation structure), as well as matrix quality, are directly related to the occurrence of M. quadrifasciata, as shown by the direct relationship between environmental structural diversity and fragment age. The matrix holding recent fragments, probably due to the sprawl of the city, is more heterogeneous than the one with the oldest fragments. The most heterogeneous matrices possess a certain balance between trees, buildings and bare soil or herbaceous vegetation coverage, making them less impermeable to bees.