Species-specific responses to pesticide use and habitat quality in wild bee communities visiting blueberry fields

Wild bees provide important pollination services to pollinator-dependent fruit crops, but their populations are threatened by environmental stressors in agricultural landscapes. In this study, we examined the major factors influencing wild bee abundance, richness, and community composition in 15 Michigan highbush blueberry fields during crop bloom in 3 years prior to the arrival of the invasive fruit fly Drosophila suzukii Matsumura (Diptera: Drosophilidae) (2004-2006) and 2 years following its arrival (2013-2014). No single measured factor consistently accounted for the majority of the variation in wild bee abundance, richness, or community composition; however, bee species richness declined with intensive pest management and increased with local and landscape floral availability in most years. Individual wild bee species exhibited widely divergent responses to pest management intensity, local floral availability, and the proportion of semi-natural habitat in the landscape. This diversity in individual bee species’ responses should be considered when developing strategies to conserve wild bee pollinators in crop systems.