Vocal behaviour reveals asymmetries in neighbour relationships in a semi-colonial raptor, the Eurasian Scops Owl Otus scops

Abstract

Territorial animals often reduce aggression towards familiar neighbours compared to unfamiliar conspecifics. However, variation in the response to different neighbours is less known. In this work, I examined the territorial behaviour of male scops owls during countersinging interactions with two familiar neighbours and I asked whether vocal behaviour of the focal male reflected dear-enemy relationships. Analysis revealed that the focal male's vocal frequency was associated with (1) the degree of instability of the territory boundary shared with a neighbour and (2) the motivation to persist in the dyadic interaction with that neighbour. Patterns of movement directed to specific individuals suggest that scops owls do discriminate between neighbours. A case of partial territory takeover was observed that was accompanied by temporal changes in vocal frequency in one of the opponents, confirming that vocal frequency is a flexible, context-dependent feature of the relationship of neighbouring scops owls.