EN
The paper discusses the directionality of slave raids of a colony of Polyergus rufescens (Latr.), an obligate European slavemaking ant species, in the presence of colonies of Formica sanguinea Latr., a facultative slavemaker, in the neighbourhood. Both these social parasites use the same host species. The results strongly suggest that P. rufescens avoided raiding the area occupied by its competitor. An explanation is offered based on a demonstrated at the same time tendency of this species to avoid dangerous places.