PhD Candidate University of Guelph Guelph, Ontario, Canada
For wild bees, living within agroecosystems may bring extensive access to nectar and pollen, but crop-bee associations may also present threats, such as exposure to agricultural pesticide residues. Protecting wild bees in agroecosystems from exposure to pesticides requires an understanding of the diversity of species that are found in those systems. Although lists of bee species associated with North American crops are scattered throughout the literature, a comprehensive compilation of those species by crop, region, and nesting guild is needed. Here, we compiled a list of wild bee species associated with 33 major crops in North America and assessed the overlap in bee species communities among crops and regions, using a pesticide exposure lens. Of the 761 crop-associated bee species retrieved, we identified 256 species of ground-nesting bees that are known to visit crop flowers. Because of their nesting and foraging behavior, we argue that these species are more likely to be exposed to pesticide residues than bee species that do not nest in the ground or feed directly on crop flowers. We further compiled lists of ground-nesting, crop flower-visiting bees that are associated with all of the four most surveyed perennial fruit crops (apple, blueberry, cranberry, strawberry) and all of the three most surveyed cucurbit crops (cucumber, Cucurbita, watermelon) in eastern North America. These lists of bee species for two important North American crop groups can be used to develop targeted protection strategies for a larger number of species and can inform the development of multi-species risk assessment schemes.
