Impact of empty flowers on foraging choice and movement within floral patches by the honey bee, Apis mellifera

Floral displays often signal the presence of nectar, but nectar may not always be present due to previous visits by nectarivores or temporal changes in nectar availability. But how does the presence of empty flowers impact the preferences of foraging honey bees for the available flowers? We aimed to test if previously rewarding flowers changed the preference relationship between neighboring flowers, and if empty flowers impacted overall visitation, in the honey bee Apis mellifera. Using artificial flowers, we showed that although empty flowers did not influence foraging choices in A. mellifera workers, empty flowers did increase movement between flowers in the patch. The presence of empty flowers also resulted in increased rates of patch abandonment. Our results suggest that while empty flowers may not directly impact foraging preferences in bees, they can have an impact on visitation within patches and in the surrounding area, with possible knock-on effects for the pollination of both the emptied flower and neighboring plants.