Avoiding perceived past resource use of potential competitors affects niche dynamics in a bird community
1 Department of Biology, University of Oulu, Oulu, FI-90014, Finland
2 Department of Biological and Environmental Sciences, University of Jyväskylä, Jyväskylä, Finland
3 Department of Ecology and Genetics/Animal Ecology, EBC, Uppsala Universit, Norbyvägen 18D, Uppsala, SE-752 36, Sweden
4 Department of Biometry and Evolutionary Biology, CNRS, University of Lyon, Villeurbenne Cedex, F-69622, France
5 Current address: Department of Zoology, Stockholm University, Stockholm, SE-10691, Sweden
6 Department of Biology, Section of Ecology, University of Turku, Turku, FI-20014, Finland
BMC Evolutionary Biology 2014, 14:175 doi:10.1186/s12862-014-0175-2Published: 15 August 2014
Social information use is usually considered to lead to ecological convergence among involved con- or heterospecific individuals. However, recent results demonstrate that observers can also actively avoid behaving as those individuals being observed, leading to ecological divergence. This phenomenon has been little explored so far, yet it can have significant impact on resource use, realized niches and species co-existence. In particular, the time-scale and the ecological context over which such shifts can occur are unknown. We examined with a long-term (four years) field experiment whether experimentally manipulated, species-specific, nest-site feature preferences (symbols on nest boxes) are transmitted across breeding seasons and affect future nest-site preferences in a guild of three cavity-nesting birds.
Of the examined species, resident great tits (Parus major) preferred the symbol that had been associated with unoccupied nest boxes in the previous year, i.e., their preference shifted towards niche space previously unused by putative competitors and conspecifics.
Our results show that animals can remember the earlier resource use of conspecifics and other guild members and adjust own decisions accordingly one year after. Our experiment cannot reveal the ultimate mechanism(s) behind the observed behaviour but avoiding costs of intra- or interspecific competition or ectoparasite load in old nests are plausible reasons. Our findings imply that interspecific social information use can affect resource sharing and realized niches in ecological time-scale through active avoidance of observed decisions and behavior of potentially competing species.