Location and color learning in bumblebees in a two-phase conditioning experiment

Bees use spatial and visual cues that characterize flowers to make dietary choices. If two such cues always appear together nonambiguously, they provide identical information. In such cases, do bees base dietary choices on one cue and ignore the other, or do they consider both cues? We allowed bumblebees to forage on two patches of artificial flowers that differed in location, color, and reward presence in a two-phase experiment. We switched either the display color, the location, or both the color and the location associated with the rewarding patch between phases. We tested for the effects of the switch on the bees' choices. Immediately following a switch in the location or both the location and the color of the rewarding patch, the bees' performance decreased, as they continued to visit the patch that was previously rewarding. This decrease did not occur when only the color of the rewarding patch was changed or in no-change controls. We suggest that the bees' foraging choices were guided mostly by a location cue when both the location and the color conveyed the same information.