Available or Preferred? Bumble Bee Floral Resource Selection Relative to Floral Resource Availability in Northern Illinois Prairies

Bumble bee species (Bombus Latreille) are experiencing global declines, and there is increased interest in their conservation. Unlike many native bee species, bumble bees are generalist pollinators and visit multiple floral species over an active season. Nonetheless, bumble bees show preferences for specific flowering species, especially when foraging pollen to feed offspring. Bumble bee species may exhibit niche separation and overlap, and floral preferences can vary depending on the species. Effective pollinator-targeted conservation and restoration practices should rely on sustaining or increasing the number of nectar and pollen-bearing plants preferred by multiple bumble bee species. Here we present an analysis of floral selection choices (as determined at the moment of capture on the transect) relative to floral availability (as determined by quadrat and visual scan surveys of blooming plants on the transect on day of bee capture). We sampled ~1000 bumble bees across three different sites in McHenry County, IL, during June-August 2019. We present for each bumble bee species what plant species were preferred beyond what was expected based on availability.