Original Article

Aggressives Verhalten von Formica-Arbeiterinnen gegen frisch geschlüpfte Arbeiterinnen von Polyergus rufescens (Latreille, 1798) (Hymenoptera: Formicidae)

Heller, G.

Abstract: Aggressive behaviour of Formica workers against freshly emerged workers of Polyergus rufescens (Latreille, 1798). – During a colony foundation of Polyergus rufescens (one Polyergus female and 200 - 300 Formica fusca workers) in the laboratory, all Polyergus callow workers were killed by their hosts immediately after emerging. The same was the case, when a new initial colony was constituted consisting of the female, the remaining Polyergus eggs and larvae and a mixed group with 200 - 300 F. cunicularia / F. rufibarbis workers. In contrast, in an isolated group of seven host workers no aggressions were observed following the emergence of the first Polyergus worker. No aggressions occurred also, when further Polyergus emerged and additional host workers were introduced by steps in the isolated group, and, finally, when the group was reunited with the colony. It can be assumed that the aggressions resulted from the particular conditions of the artificial nest: The Polyergus callow workers were exposed immediately after emergence to a large number of host workers, whereas in the narrow galleries of natural nests the contact possibilities might be more restricted. This might have prevented a success of the integration strategies (chemical insignificant cuticular profile, abdominal trophallaxis) of Polyergus workers.