Extraterritorial forays by great tits are associated with dawn song in unexpected ways

Abstract

Abstract Conspicuous male signals often play an important role in both attracting mates and deterring rivals. In territorial species with extrapair mating, female and male forays to other territories may be an important component underlying female choice and male mating success and might be influenced by male advertisement signals. Yet, whether off-territory foraying is associated with male signals is still not well understood. Here, we tested how female and male forays are associated with short-range visual and long-range acoustic signals (dawn song). We used an automated radio tracking system to follow the movements of wild great tits (Parus major) to other territories in relation to male dawn song, plumage ornaments, and extrapair paternity. We show that both sexes frequently forayed into others’ territories throughout the breeding period. Movements of both males and females were associated with male song but not with plumage ornaments. Contrary to our expectations, females stayed away from territories where males sang elaborately, whereas males were attracted to those territories. Moreover, neither female nor male forays were associated with the occurrence of extrapair offspring. Our results, thus, suggest that, although forays into other territories are associated with male dawn song, females may not be attracted and males not repelled by dawn song. This sheds a different light on the sex-specific effects of male advertisement signals, expanding the view on the selection pressures shaping such communication systems.