Trapped: Assessing Attractiveness of Potential Food Sources to Bumblebees

Unrewarding artificial flowers that trapped approaching bumblebees were used here for the first time to assess the effects of several floral characteristics on floral attractiveness to bumblebees that never obtained food from flowers. Floral size and floral scent had no discernable effect. In a comparison between two colors (white and blue) and two shapes (radial and square), choice proportions for blue radial flowers were significantly greater than chance. Our proposed method is an alternative to prior training, with food associated either with visual or olfactory stimuli, which is unnecessary to obtain floral preferences by free-flying bumblebees exploring potential food sources.