Behavioural and socially parasitic relations between Polyergus rufescens (Latr.) and Formica polyctena Först. (Hymenoptera: Formicidae)

Polyergus rufescens (Latr.), an obligate slave-maker, and Formica polyctena Först., an aggressive, territorial wood ant species, rarely co-occur in the field, and there are almost no data on their mutual relations under natural conditions. These interactions were studied in the Bialowieza Forest (NE Poland), based on two P. rufescens colonies (with Formica fusca L. slaves) nesting within the territories of F. polyctena. The wood ants routinely searched the immediate vicinity of P. rufescens nests, whereas P. rufescens ants raided F. fusca colonies very close to F. polyctena nests or their columns passed right next to them, they eventually crossed wood ants’ foraging and removal routes, and even directly attacked F. polyctena colonies and robbed their brood. Interspeciflc relations in these particular situations are described and discussed in the contexts of supposed chemical camouflage/mimicry of P. rufescens and interspecific competition hierarchy in ants.