Submitted to: Journal of Animal Behavior
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/29/2003
Publication Date: 6/1/2003
Citation: Ellis, J.D., Hepburn, R., Ellis, A.M., Elzen, P.J. 2003. Social encapsulation of small hive beetles (Aethina tumida Murray) by European honeybees (Apis mellifera). Journal of Animal Science. 50(3):286-291. Interpretive Summary: The behavior of Cape honey bees toward colony-invading small hive beetles has been termed "social encapsulation". The purpose of this study was to document the presence or absence of this behavior in European honey bees, which have not co-evolved with the small hive beetle as the Cape bee has. We found that colonies of European honey bees also encapsulated invading adult small hive beetles, but was variable between queen lines tested. It thus appears that European honey bees react to colony invasions by the small hive in a similar manner as the African Cape bee.
Technical Abstract: European and African honeybees (Apis mellifera L.) utilize social encapsulation to control Aethina tumida Murray (small hive beetle), a honeybee colony scavenger of growing international importance. Although social encapsulation of A. tumida by African honeybees is well documented, social encapsulation by European honeybees is less understood. In this study, we quantify A. tumida and European honeybee behaviours that are associated with social encapsulation of A. tumida, describe colony and time (day and night) differences in these behaviours, and detail intra-colonial and inter-colonial, encapsulated A. tumida distributions. The number of A. tumida encapsulations and A. tumida per encapsulation differed significantly between colonies. The number of bees guarding per encapsulated A. tumida making antennal contact with guarding bees and mating did not differ between colony or time. Aethina tumida activity and feeding from guarding bees increased significantly at night (although the proportion of guarding bees feeding A. tumida did not increase). Colonies differed in the proportion of guarding bees biting at encapsulated A. tumida. There were no colony or time differences for the proportion of guarding bees making antennal contact with encapsulated A. tumida. Lower proportions of guarding bees were biting the area around A. tumida encapsulations at night. Only 7% of A. tumida were found among the combs during both times; all other encapsulated A. tumida were distributed around the nest periphery. These findings highlight complex interactions between encapsulated A. tumida and guarding bees, allowing comparisons to be made between European and African honybee social encapsulation systems.