EXISTENCE AND PHYSICAL-PROPERTIES OF PHEROMONES BY WHICH WORKER HONEYBEES RECOGNIZE QUEENS

A method is described of detecting substances by which worker honeybees distinguish a queen from a worker when they can touch her. It has been used successfully in all but one month of the year, is relatively quick, involves little handling of bees or damage to colonies, and is statistically reliable. The minimum amount of material that can be detected is about 0.1 queen equivalent in each of 16 replicates. Recognition could be elicited by extracts of queen heads, but was very difficult to detect with any of the acid substances hitherto identified in queen heads. The active substances are fairly stable in air at 100°C for 1 h, and probably in ethanol at room temperature for at least 16 years. They do not distil in still air at 60–100°C and atmospheric pressure. They are probably acid, and perhaps decay in air when made alkaline. Most of the active material is in the queen’s head, but some is in her abdomen. Active material was recovered from the bodies of worker bees of a colony with a queen and brood, but the active material appeared to be associated more with the presence of the brood than with that of the queen. © 1979 International Bee Research Association.