Effects of climate change and habitat loss on a forest-dependent bee species in a tropical fragmented landscape

1. Climate change and deforestation are suggested to be the main drivers of decline in pollinators. Forest-dependent species are expected to be the most affected and Euglossa marianae Nemesio (Hymenoptera: Apidae), an endemic species of the highly fragmented Brazilian Atlantic Forest (AF), is believed to be declining as a consequence of human impact. 2. Over the last 17 years, we carried out field surveys to unveil its distribution, allowing us to investigate the potential effects of global climate change on this species, from the last glacial maximum into the future, using species distribution models. Our main goals were to: (i) identify populations potentially under risk of extinction given future climate change; (ii) quantify the amount of climatically suitable and climatically stable areas for E. marianae within AF; (iii) evaluate the area that are available as natural habitat and under legal protection, in an attempt to indicate priority areas to preserve this species. 3. The most stable areas for maintaining populations of E. marianae were located in southern Bahia and northern Espirito Santo states, a region severely affected by deforestation and with several protected areas. Climate change per se does not seem to be the major problem for E. marianae. It may constitute an indirect problem given the limited dispersal abilities of this species, however. 4. Climatically suitable areas will probably increase southwards in the future, but the extreme fragmentation of AF adds great uncertainty as to whether the species will disperse southwards, to regions such as the 'Serra do Mar' in northeastern Sao Paulo.