Interspecific social information in habitat choice

Abstract

Social information use is common between individuals of same species, especially in habitat choice. Social information use between species is much less studied, but could be common as well, especially in situations where ecologically similar species have unequal access to information. Such situation arises in boreal forests between small cavity-nesting passerines, such as migrant Ficedula spp. flycatchers and resident tits Parus spp. Earlier research has shown that migrants are attracted to residents, and in this study I aimed to further investigate this phenomenon. By manipulating the density and spatial proximity of resident tits, I demonstrated that tits have a positive effect on the fitness of pied flycatchers F. hypoleuca, plausibly due to accelerated assessment of habitat quality. I also analysed the nest-site choice process of collared flycatchers F. albicollis, and showed that they avoid conspecifics, but appear to be attracted to tits. Social learning is a special case of social information use, where the individual gains generalised knowledge about some feature in its environment. By simulating arbitrary preferences of tits, I showed that both pied and collared flycatcher can blindly copy the preferences of residents. This could result in transfer of local adaptations and increased niche overlap. Furthermore, I developed and clarified the general concept of social information use, and demonstrated its contextual and taxonomic diversity. Social information is a process linked to process of another individual, with inevitable temporal, spatial and ecological extent, costs and potential trade-offs. Social information use between species is common and diverse, occurring in invertebrates, amphibians, fish, birds and mammals.