Flexibility in European starlings’ use of social information: experiments with decoys in different populations

Individuals confronted with novel environments, for instance recently modified environments such as towns or recently occupied habitats such as colonization fronts, have to cope with a lack of information about the location of resources. We hypothesized that, under these conditions, individuals of a social species such as European starlings, Sturnus vulgaris, would be more responsive to social cues indicating food presence than individuals belonging to populations already established in a well-known habitat. To test this hypothesis, we displayed starling decoys with various age, group size and interindividual distance characteristics in feeding postures to evaluate their attractiveness to starlings from towns and colonization fronts and noted whether attracted individuals joined particular decoy groups. Our results supported our hypothesis that sensitivity to social cues varied according to the population’s history, and we suggest that these cues enhance the success of starlings in occupying new habitats.