Meeting Abstract
We compared honey bee foragin strategies based on reward and effort on an artificial flower patch. The study aimed to test if bee foraging choice is based on past experience of reward quality and effort (incentive contrast) or on energy gain over time (optimal foraging). The bees visiting a feeder with lower sucrose concentration were trained to visit the flower patch. The patch has 18 blue and 18 white Plexiglas “flowers” of 1.2”x1.2” with a central well for “nectary”. The effort to visit flowers was increased by inserting short (~5mm) or long(~20mm) pins in a pattern on the flowers. We presented low (0.5M), intermediate (1M), or high (2M) reward of 4µl sucrose solution in flowers. In experiment 1 bees began on flat flowers with 1M reward, after 35 visits switched to short stamen flowers (35 visits), later to long stamen flowers (35 visits). After the long, difficult flowers in the 2nd control phase, bees were asked to chose high reward high difficulty blue flowers vs low reward low difficulty white flowers (50 visits). In Experiment 2 bees were asked to make the same choice after the short, low difficulty flowers in the 1st control phase. The Incentive Contrast Hypothesis predicts difference in choices of bees in Experiment 1 and 2. In contrast, the Optimal Foraging hypothesis predicts no difference. Significantly greater number of bees (Median Test, P<0.03, Exp 1 median =0; Exp 2 median =3) visited more of the white, low difficulty low reward flowers in Experiment 2 (n=8) in comparison to Experiment 1 (n=11). Results support the Incentive Contrast hypothesis. NSF REU grant 1560389 and NSF PIRE grant 1545803 supported this research at Kalloni Bay, Lesvos, Greece.
