BALLING BEHAVIOR IN THE HONEY-BEE IN RESPONSE TO EXOGENOUS QUEEN MANDIBULAR GLAND PHEROMONE

Honey bee (Apis mellifera) colonies generally respond to the introduct ion of a foreign queen by aggressively surrounding or 'balling' the ne w queen. We explored the role of queen mandibular gland pheromone (QMP ) in initiating balling behaviour. The addition of a synthetic blend o f QMP to the abdomen of worker bees initiated balling behaviour of the se workers when re-introduced into their own colony. There was a posit ive, dose-dependent relationship between the number of balls formed, t ime to ball formation and size of balls formed. When the QMP dose was below that normally found on a queen, 10(-3) queen equivalents, it res ulted in significantly slower ball formation and smaller bail diameter . The acid components of the five-component QMP elicited balling behav iour while the aromatic components did not, but the full blend elicite d the strongest response. Stinging behaviour was the most prevalent an d persistent factor preceding the formation of balls. We concur with o thers who have proposed that a 'marking' pheromone is released when an aggressive worker flexes her abdomen, and that the release of this ph eromone causes ball formation. There were no obvious changes in reside nt queen behaviour while balling of QMP-treated workers was occurring. We conclude that queen mandibular gland pheromone is a significant si gnal in foreign queen recognition and the initiation of balling behavi our.