The Arctic is considered a relatively pathogen-poor environment. Most arctic-breeding birds, however, occupy the Arctic only seasonally. On their travels to and from arctic breeding grounds they move through a variety of other environments for wintering and staging, where they may come into contact with more and diverse pathogens. Thus, it is largely an open question if arctic-breeding populations do actually benefit from their (energetically costly) migrations by escaping pathogen-rich environments or not. Such question is furthermore of interest with respect to the spread of zoonotic diseases like, for instance, avian influenza viruses. I study this problem in the barnacle goose Branta leucopsis, a traditionally arctic-breeding species that recently has colonised new environments in the temperate zone along the flyway. Such a study system allows intraspecific comparisons of arctic long-distance migratory, temperate short-distance migratory and sedentary populations, all sharing common wintering grounds along the North Sea. In my presentation I will investigate prevalence of antibodies directed at AIV in eggs, growing young and moulting adult geese from colonies along the Barents Sea, the Baltic and the North Sea.