Honeybee Colonies (Apis mellifera L.) Perform Orientation Aggressiveness Which Varies Among Bred Lines

Abstract

Honey bees (Apis mellifera L.) express complex behavioral patterns (aggressiveness) to exhibit defensive mechanisms for their survival. Their phenotypic expression of aggressive behavior is influenced by internal and external stimuli. Knowledge of this behavior is recently important though beekeepers are still faced with the challenges of selecting aggressive and less-aggressive bred lines. Field evaluation of aggressiveness among bred lines of honey bees is required to overcome the challenges. Chemical cues (alarm pheromone and isopentyl acetate mixed with paraffin oil), physical and visual stimuli (dark leather suede, colony marbling and suede jiggling) were used to evaluate aggressiveness and orientation among five bred lines of honeybee colonies. Our results showed that both chemical assays recruited bees but the time of recruitment was significantly lower for alarm pheromone. Honeybees’ response to both assays culminated to stings which differed among bred lines for alarm pheromone and paraffin when colonies were marbled. Honeybee aggression varied among bred lines and was higher in more aggressive bred lines compared to less-aggressive bred lines. Our findings suggest that it is crucial to repeatedly evaluate orientation aggressiveness at the colony level and among bred lines when selecting breeding colonies.