SANDERSON, C.E.; HILL, P.S.M.; WELLS, H.; University of Tulsa; University of Tulsa; University of Tulsa: Honey bee response to differences in handling time, rewards and flower colors

Foraging behavior of honeybees (Apis mellifera) was studied in order to examine the interaction that differences in reward, flower handling-time, and flower color have on the decision process involving choice of flowers to visit. Reward and handling time were correlated to flower color so that bees had to use flower color as a cue to maximize harvest rate. Bees were tested on blue-white and on blue-yellow dimorphic artificial flower patches. Rewards were varied by offering alternative sucrose molarity nectars, while handling-time was varied by using different flower well-depths. Tests were made with 2ul and again with 6ul nectar rewards. Bees visiting a blue-yellow dimorphic flower patches each showed very high fidelity to one flower color, some to blue and others to yellow, irrespective of handling-time. Those bees rarely even sampled the alternative color, whether it was blue or yellow. However, when given a choice of visiting blue or white flowers having identical rewards, bees avoided the color associated with the greater handling-time. Yet, when the higher quality reward was placed in flowers having a higher handling-time, bees selected the flower color associated with shallow wells over the color associated with deep wells at the cost of obtaining a lower harvest rate. These results on blue-white dimorphic flower patches suggest that when considering foraging options involving reward and handling-time choices that bees use a comparative method of evaluation. That is, foragers do not use a single currency(calories/second). Nevertheless, color choice offered can limit forager consideration of either reward or handling-time differences as the results using blue-yellow dimorphic flower patches demonstrates.