Food restriction and threat of predation affect visual pattern choices by flower-naïve bumblebees

Abstract

The aim of this study was to determine whether a preference by flower-naïve bumblebees could be created or enhanced by manipulating variables relevant to food collection and to defense against predation. In two experiments, colonies of bumblebees (Bombus impatiens) were deprived of pollen, exposed to CO2, or neither. Choices of individual workers in a radial arm maze were monitored. In Experiment 1, both variables lead to a preference for corridors occupied by a conspecific bee. The effect was specific: no change in preference for corridors occupied by other objects (a coin and a piece of Styrofoam) was detected. In Experiment 2, radial and concentric patterns were used, both of which were unoccupied. Only pollen deprivation increased preference for radial stimuli, while CO2 had no discernible effect. Preferences for visual patterns by bees leaving their colony for the first time are modulated by variables that affect the internal state of the bees in problem-specific ways