Standardized protocols for collecting data on bee-flower interactions and the associated floral community

Pollen and nectar from flowers constitute the primary food resources of bees, inextricably linking bee and flowering plant communities in space and time. Thus, our understanding of bee biology and distribution can be greatly enhanced by documenting interactions between bees and their host plant species. Plant-pollinator interaction data are routinely collected in studies with diverse research goals, but the lack of standardization in data collection has limited our ability to integrate datasets and address outstanding questions in bee ecology, conservation, and pollination biology. Here, we provide standardized protocols for (A) documenting plant-pollinator interactions and (B) quantifying associated floral resources available to foraging bees. These protocols can be combined for a more detailed understanding of plant-pollinator interactions and can be applied in inventories, surveys, and monitoring programs of bees. We also provide case studies demonstrating their application. We discuss tradeoffs that are inevitable in any methodological approach, including the use of lethal versus non-lethal sampling approaches, and highlight the need to prioritize rigorous testing of the scalability and generalizability of current methodologies. These protocols are part of a series developed in association with the U.S. National Native Bee Monitoring Network to standardize bee monitoring practices.