Vibration and sound communication in solitary bees and wasps

Females of solitary bees (Colletes cunicularius L.) and of digger wasps (Bembix rostrata L.) produce buzzing sounds and are known to secrete volatile odours when digging their way from the subterranean nests to the soil surface. The odours allow patrolling males to determine the approximate position of the digging virgin female. The buzzes are measured as substrate‐borne sound (soil buzz vibrations) and as air‐borne sound (soil buzz sounds). Play‐back experiments suggest that the soil buzzes are used by the males as additional cues for localization. Faint buzz sounds are emitted regularly by the male during genital contact in copulation. They may serve to change the receptivity of the female. Intense and broadband buzz sounds are produced by bees of either sex, if restrained from moving, perhaps serving to deter predators.