Managed and wild pollinators often cohabit in both managed and natural ecosystems. The western honeybee, Apis mellifera,
is the most widespread managed pollinator species. Due to its density and behaviour, it can potentially influence the foraging
activity of wild pollinators, but the strength and direction of this effect are often context-dependent. Here, we observed
plant–pollinator interactions in 51 grasslands, and we measured functional traits of both plants and pollinators. Using a multimodel
inference approach, we explored the effects of honeybee abundance, temperature, plant functional diversity, and trait
similarity between wild pollinators and the honeybee on the resource overlap between wild pollinators and the honeybee.
Resource overlap decreased with increasing honeybee abundance only in plant communities with high functional diversity,
suggesting a potential diet shift of wild pollinators in areas with a high variability of flower morphologies. Moreover, resource
overlap increased with increasing trait similarity between wild pollinators and the honeybee. In particular, central-place
foragers of family Apidae with proboscis length similar to the honeybee exhibited the highest resource overlap. Our results
underline the importance of promoting functional diversity of plant communities to support wild pollinators in areas with
a high density of honeybee hives. Moreover, greater attention should be paid to areas where pollinators possess functional
traits similar to the honeybee, as they are expected to be more prone to potential competition with this species.