Patterns of community-wide interactions have been evaluated at the species-level overlooking how differences in individual behavior can help structure patterns of species interactions. We built and compared species- and individual-level networks using pollen loads on pollinators in a serpentine plant community. Interactions were two times more specialized at the individual-level suggesting high individual niche partitioning. We observed differences in individual specialization among pollinator species, which may differentially impact pollination success despite similar species niches. Intraspecific trait variation did not impact pollinator niche, suggesting other factors related to resource use drive plant--pollinator network structure. Female bees were more specialized than males, suggesting sex-based differences contribute to individual specialization. Using individual-level networks this study links individual foraging patterns with population-level processes that scale up to structure species-level plant--pollinator networks. In doing so, this study aids in our understanding of perceived conflicts between specialization and generalization in plant--pollinator communities.

Flower-visiting insects in agroecosystems forage on field-edge weeds often exposed to agrochemicals that may compromise the quality of their floral resources. We conducted complementary field and greenhouse experiments to evaluate the: 1) effect of low concentrations of agrochemical exposure on nectar and pollen quality and 2) relationship between floral resource quality and insect visitation. We found pollen amino acid concentrations were negatively affected by herbicide exposure, and pollen fatty acid concentrations were negatively affected by fertilizer exposure, while nectar sugar concentrations were positively affected by both fertilizer and herbicide exposure. These variations found in the greenhouse helped explain insect visitation in the field study. The insect visitation rate correlated with floral resource quality. An interaction between pollen protein and floral display suggested pollen protein drove insect abundance for larger display sizes. We show that flower-visiting insects can detect and respond to changes in floral resource quality mediated by agrochemicals.