How much do rare and crop-pollinating bees overlap in identity and flower preferences?

1. The biodiversity-centered approach to conservation prioritizes rare species, whereas the ecosystem services approach prioritizes species that provide services to people. The two approaches align when rare species provide ecosystem services, or when both groups of species benefit from the same management action. We use data on bee pollinators and the plant species they forage on to determine if there are rare species among the most important crop pollinators, and the extent to which plant species selected to support crop pollinators would support rare species as well.
2. To assess the plant preferences of these two groups of bee species, we collected two datasets on plant-pollinator interactions, one experimental and one observational. The experiment consisted of monospecific plots of 17 plant species from which we collected bees over three years. The observational data consisted of bees collected from 66 species of plants growing in semi-natural meadows, also over three years.
3. Ni...