Similar studies on movements of mallards are being planned or conducted in different European countries
(France: M. Artois, National Veterinary School, Lyon; Germany: Wolfgang Fiedler, Radolfzell; Portugal: D.
Rodriguez, pers. communication). The results of the different studies will help us to improve our understanding
of the importance of mallard as vectors of avian influenza viruses. In particular, this study will provide
scientific evidence on the basis of which risk zones can be established, that has been lacking so far.