Queen excluders enhance honey production in African honey bees, Apis mellifera, by limiting brood rearing during peak nectar flow
Nuru Adgaba, Ahmed A Al-ghamdi, Mebrat Hailu, Awraris G Shenkute, Mohammed J Ansari, H Randall Hepburn and Sarah E Radloff
Unlike honey bees in temperate regions, those in tropical Africa exhibit a strong tendency towards continuous brood rearing rather than storing honey, which is a behaviour that lowers both the productivity and commercial value of African bees. In this study, the possibility of maintaining a balance in resource allocation between brood rearing and honey storage was assessed. Twelve colonies were examined, half of which were fitted with queen excluders three weeks before an expected honey harvest, while half were used as controls. Data on the honey yields and brood populations of the colonies were collected during four flowering seasons over a two-year period. The mean brood populations of all of the colonies did not differ significantly when the queen excluders were inserted into the six treatment colonies. However, at honey harvest, three weeks later, there was a highly significant difference in the mean brood population between the treatment and control groups. Colonies without queen excluders continued to rear brood, even during peak honey flow periods. The partial limiting of queen egg laying using queen excluders significantly reduced the average colony brood population compared to the control group at peak honey flow. The seasonal average honey yields were significantly different between the control and treatment groups. Under African conditions, in which bees tend to rear brood continuously even at peak honey flow and when flowering periods are short, the use of queen excluders during such periods would probably enhance honey yields of colonies.