Potential pollination maintenance by an exotic allodapine bee under climate change scenarios in the Indo-Pacific region

Recent studies suggest an alarming decline in pollinators across many regions of the world due to multiple factors. One potential factor is climate change, which poses both direct and indirect threats to pollinator populations. To help ameliorate the impact of declining populations on the function of ecological and agricultural systems, there is a need to identify species that may adapt to limit the magnitude of this pollination deficit. The South West Pacific has a highly depauperate endemic bee diversity and numerous non-indigenous species, including honeybees. One allodapine bee, Braunsapis puangensis, has been accidentally introduced to Fiji where it has rapidly spread across multiple islands and become locally abundant. It is a long-tongued bee, unaffected by honeybee pathogens, and has the potential to become an important crop pollinator. Here, we model the distribution of this species under different climate scenarios to determine how it is likely to respond to future climate change. We show that its distribution is unlikely to contract, but potentially expand with climate warming. These scenarios therefore indicate that the plasticity in B. puangensis populations may allow it to represent an important crop pollinator in this region should honeybee populations decline.