Motion discrimination by Bombus impatiens(Hymenoptera: Apidae)

AbstractMobility of flowers in the wind has been proposed to affect the performances of pollinators in landing on flowers, nectar extraction, and pollen dispersal. Our study examined the preferences of worker Bombus impatiensCresson (Hymenoptera: Apidae) for landing on and feeding from immobile or mobile artificial flower. Mobile flowers moved at varied frequencies (0.1–3.0 Hz) and in different directions, horizontal H(left to right wave) and vertical V(from en-facepresentation at the lowest point to horizontal presentation at the zenith). We found that the bees showed no preference for mobile or immobile flowers. In general, we found that landing ability (time spent from the bees entering the testing arena to landing and starting to feed on the artificial flower) decreased as frequency (Hz) or speed of motion (cm/second) increased. Directionality of waving affected performance with the bees being able to forage from horizontally moving flowers better than from vertically moving flowers. Experience played a major role in improving individual performances. We also found that the bees could differentiate between horizontally and vertically waving flowers as well as between frequencies or speeds of motion.