title: With whom to dine? Ravens' responses to food-associated calls depend on individual characteristics of the caller.
abstract: Upon discovering food, common ravens,Corvus corax, produce far-reaching 'haa' calls or yells, which are individually distinct and signal food availability to conspecifics. Here, we investigated whether ravens respond differently to 'haa' calls of known and unknown individuals. In a paired playback design, we tested responses to 'haa' call sequences in a group containing individually marked free-ranging ravens. We simultaneously played call sequences of a male and a female raven in two different locations and varied familiarity (known or unknown to the local group). Ravens responded strongest to dyads containing familiar females, performing more scan flights above and by perching in trees near the respective speaker. Acoustic analysis of the calls used as stimuli showed no sex-, age- or familiarity-specific acoustic cues, but highly significant classification results at the individual level. Taken together, our findings indicate that ravens respond to individual characteristics in 'haa' calls, and choose whom to approach for feeding, i.e. join social allies and avoid dominant conspecifics. This is the first study to investigate responses to 'haa' calls under natural conditions in a wild population containing individually marked ravens.
authors.affiliation: Department of Cognitive Biology, University of Vienna, Vienna, Austria ; Konrad Lorenz Forschungsstelle, Core Facility, University of Vienna, Gruenau im Almtal, Austria.
authors.forename: Georgine
authors.initials: G
authors.lastname: Szipl
authors.affiliation: Department of Cognitive Biology, University of Vienna, Vienna, Austria ; Konrad Lorenz Forschungsstelle, Core Facility, University of Vienna, Gruenau im Almtal, Austria ; Department for Psychotherapy and Biopsychosocial Health, Danube University Krems, Krems, Austria.
authors.forename: Markus
authors.initials: M
authors.lastname: Boeckle
authors.affiliation: Konrad Lorenz Forschungsstelle, Core Facility, University of Vienna, Gruenau im Almtal, Austria ; Departamento de Ciencias Agro-Forestales, University of Valladolid, Valladolid, Spain.
authors.forename: Claudia A F
authors.initials: CA
authors.lastname: Wascher
authors.affiliation: Department of Cognitive Biology, University of Vienna, Vienna, Austria.
authors.forename: Michela
authors.initials: M
authors.lastname: Spreafico
authors.affiliation: Department of Cognitive Biology, University of Vienna, Vienna, Austria ; Konrad Lorenz Forschungsstelle, Core Facility, University of Vienna, Gruenau im Almtal, Austria.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bugnyar
keywords: Corvus corax; common raven; food-associated call; playback; recruitment