Over the years, drones (male honey bees) have been maligned by human society. The very word connotes slothfulness or worse. Many beekeeping books suggest that drones are nothing more than a kind of parasite in the colony, eating up the beekeeper’s hard-won gain. Actively managing colonies to limit the number of drones is traditionally recommended. The drone is only given his due grudgingly in queen rearing where his number is translated into profits through insemination of virgin queensQueensvirgin.
Although the drone may be an outcast in human society, he is not in the honey bee’s. Beyond the well known task of courting (inseminating) the queen, drones provide a measure of well being for the colony. Drone activity has not been well studied. He may well be involved in maintaining nest temperature and other critical duties which have so far escaped detection.
If there are too many drones, a colony suffers to be sure. Excessive numbers may indicate a colony imbalance caused by a failing or absent queen. The drones themselves, however, should not be blamed for this condition. Rather, the beekeeper is often responsible for allowing the colony to reach such a state.
There is also the notion that drones provide a flexible nutritional resource within the colony. Drone eggs and larvae are subject to be eaten when environmental conditions are marginal. This suggests that drone brood is in fact a dynamic protein bank. The proceeds in this bank can either be spent, by letting drones mature, or saved, when the going gets rough, by consuming drone larvae.1
Finally, evidence exists that Varroa mites prefer to parasitize drone over worker brood. The drone life cycle (24 days from egg to adult) is longer than that of the worker (21 days from egg to adult). Three or so added days of development time provided by drones ensures a higher mite population. Drone comb slipped into the nest by the beekeeper and then removed when full is a valid control measure.
A French study isolated chemicals in drone larvae that attracted Varroa mites.2 Italian beekeepers are experimenting with using drone brood as a Varroa trap or sink.3 A sheet of drone foundation divided in thirds is inserted into the center of the brood nest. When the comb is drawn out, the queen lays drone eggs and the resulting larvae are preferably parasitized by Varroa. At 8 day intervals, one third of the comb with parasitized capped brood is removed. This procedure is repeated throughout the active season. It is, therefore, ironic that male bees, once thought to be so deleterious to a bee colony, may become a major key to solving one of the greatest problems currently affecting honey bees and beekeepers..
1 Personal communication, Taber, S. author of Breeding Super Bees, A.I. Root Co., 1987.
2 Y. Le Conte, G. Arnold, J. Trouiller, C. Masson, B. Chappe, and G. Ourisson, “Attraction of the Parasitic Mite Varroa to the Drone Larvae of Honey Bees by Simple Aliphatic Esters, Science, Vol. 245, pp. 638-639, August, 1989.
3 F. Marletto, A. Manino and A. Patetta, “Tecniche Manipolative di Lotta alla Varroa: Considerazioni Dope Due Anni di Esperienze,” L’Apicoltore Moderno, Vol. 81, No. 2, pp. 77-84, March-April, 1990.