Conservation strategies for wild bee pollinators require information on community and species-level responses to environmental resources and stressors, including bees’ responses to habitat composition and agricultural practices at different scales. The objectives of this research were to 1) determine the direction and variability of wild bee community responses in blueberry fields to pest management practices and landscape composition by revisiting previously-sampled farms where pesticide use has increased over recent years; and 2) to determine which habitats in Michigan farm landscapes are most suitable for soil-nesting bees, and whether bees nest preferentially in wildflower plantings over nearby unrestored habitats. The abundance, richness, diversity, and community composition of wild bees exhibited strong negative responses to insecticide program risk at the field scale over five years of sampling in 15 blueberry fields. In general, solitary bee species had more negative responses to insecticide risk than social species. Bees responded most strongly to landscape composition at the smallest scale studied (300 m). Wild bee abundance declined with decreasing area of forest and the associated increase in settled areas, while bee richness and diversity declined primarily with insecticide risk. Using emergence traps, I found that wildflower plantings generally support a greater abundance of soil-nesting bees than other habitat types in the surrounding landscape. Bee nesting abundance was higher in mature wildflower restorations than newly-established plantings, indicating that wildflower restorations are an effective conservation tool for building bee populations over time through the provision of both floral and nesting resources.
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