D3332: Impacts of honey bee competition and resource availability on wild bee fitness

Managed honey bees (Apis mellifera) have been widely introduced outside their native range. When abundant, honey bees can compete with wild bees for scarce pollen and nectar resources and mounting evidence suggests that resource competition has the potential to negatively impact wild bee fitness. However, we lack a clear understanding of when and where negative fitness impacts are likely to occur, limiting our ability to inform policy regarding the sustainable management of honey bees on public lands. Using a manipulative cage experiment, we assessed impacts of honey bee competition on Bombus impatiens foraging and reproduction. This research is still ongoing, but preliminary trials suggest that honey bee competition reduces B. impatiens reproduction, with more severe declines in offspring production when floral resources are limited.