Cavity-nesting bee nesting success across gradients of floral resources and land-cover

Abstract

Floral resource limitation and habitat loss resulting from land-cover change can influence the reproductive success of solitary cavity-nesting bee species. However, surprisingly scant knowledge exists on the population dynamics and demographics for most bee species, and even less knowledge exists regarding how floral resources or land cover may influence nesting rates and nesting success. We measured nesting rates and nesting success for a community of cavity-nesting bees across gradients of floral abundance, floral richness, and land cover in the Prairie Pothole Region of North Dakota. Specifically, we were interested in studying how nest occupancy and nesting success of cavity-nesting bees were related to nests located near managed grassland, wetlands, and woodlands. Surprisingly, we observed no relationships between bee nesting metrics and nearby land cover. We also observed no significant influence of floral abundance or floral species richness on any recorded bee nesting metrics. While other research has found variability in floral resources across land cover within the Prairie Pothole Region, we were unable to detect strong influences of either floral resources or land cover on nesting of solitary cavity-nesting bee species in our study system.