040— Evaluating the Use of Artificial Nests by Native Bees

Many cavity-nesting native bees are important pollinators. These bees rear their brood in hollowed out stems or other similar holes. Relationships between bee abundance and artificial nest occupation were evaluated across several locations on campus. Nest boxes consisting of approximately 40 hollow tubes in wooden frames were monitored at 4 locations on campus that likely differ in bee fauna. A wooden frame (the “bee barn”) that supported eleven nest boxes was established in spring 2019 among the native plant gardens of the Spencer J. Roemer Arboretum, with a twelfth box added for this study. Six boxes isolated into sets of two were placed in the Arboretum wildflower area, the back meadow area of the Arboretum, a no-mow zone, and the eGarden. Nest-building activity was observed by recording the tube-filling material for each cavity and the types of insects observed utilizing nest tubes. Insects were sampled with bee bowls, blue-vane traps, and net surveys of each site. This study provided an understanding of which bee species are supported in artificial cavity nests, how artificial nest occupants compare to the surrounding bee fauna, how nesting cavities are filled throughout the season, and whether bees prefer high density over isolated nesting sites.