Researcher, Social behaviour and physiology Behavioural Ecology and Self-Organizsation, CEES, The University of Groningen, The Netherlands My main interests are in determining the effects of social allies on the physiological stress response. My colleague Brigitte Weiss, who also joined the barnacle field group in Spitsbergen this year, and myself are greatly interested in social systems of birds, particularly geese. In the past we have been investigating this topic in Greylag Geese at the Konrad Lorenz Field Station in Gruenau, Austria. Last year I moved to the University of Groningen (NL) in the research group of Prof. Jan Komdeur. Funded by a research grant from the NWO, Brigitte and I are now attempting to collect data, comparable to our collection in Gruenau, on the wild Barnacle Goose flock in Spitzbergen. Our main objectives are to collect not only behavioural data on social interactions in barnacle goose families, but also to collect fecal samples from all family members to determine stress hormone metabolites. This will give us information on the responsiveness of one of their major stress coping systems.