Hygienic Behavior of Cape and European Apis mellifera (Hymenoptera: Apidae) toward Aethina tumida (Coleoptera: Nitidulidae) Eggs Oviposited in Sealed Bee Brood

Abstract In this study, we tested for the presence and efficacy of hygienic behavior by Cape honey bees in South Africa and European honey bees, Apis mellifera L. (Hymenoptera: Apidae), of mixed origin in the United States toward Aethina tumida Murray (Coleoptera: Nitidulidae) eggs oviposited in sealed bee brood. We looked for colony differences in removal rates of brood in cells with cappings perforated by A. tumida within each subspecies to identify colonies within location that display superior hygienic behavior. Finally, we determined the oviposition rate (number of A. tumida-perforated cells actually oviposited in by A. tumida/total number of A. tumida-perforated cells) in A. tumida-perforated cells and the number of A. tumida eggs oviposited in each cell. There were no colony differences within subspecies for the removal of normal capped brood, artificially perforated brood (capped cells perforated by experimenter with a pin), and A. tumida-perforated brood. For both subspecies, the bees removed significantly more A. tumida-perforated brood than either normal or artificially perforated brood. A. tumida oviposited significantly more eggs per cell in Cape colonies than in European colonies, but the oviposition rate in A. tumida-perforated cells did not differ between Cape and European colonies. Both subspecies removed a proportion of A. tumida-perforated brood statistically indistinguishable from the proportion of A. tumida-perforated brood containing A. tumida eggs. Thus, both Cape and European A. mellifera preferentially remove the contents of A. tumida-perforated cells in which A. tumida have actually oviposited.