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Résumé :
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Mapping of ringing recoveries gives very impressive migration patterns that are, however, often misleading. Most of people looking at them believe that almost all European Passerines migrate SW to, or through, south-western Europe. But this impression is false for many species because the number of recoveries often depends more on hunting pressure and a level of education of the people living there than on the number of ringed birds migrating or wintering on the area. Detectability of rings is close to null in the eastern and southeastern parts of Europe and, additionally, bird ringing on this area is negligible in relation to the western Europe. Results of other than bird ringing studies (orientation field experiments) suggest that most of birds from this area migrate in southeastern direction. There were pilot studies with a new field method of setting preferred directions of nocturnal migrants carried out in Poland, Estonia, Ukraine, Russia (as far as Kazan to the East) and Israel. The method is very simple and cheap in application - it is possible for one person to do 40 or more experiments at one stand per day. Robins tested at the Polish Baltic coast show preference to directions leading to winter-quarters situated more easterly than Italy in 36-41%, in central Poland 84%, and near Moscow 87%. To get such information out of the ringing needs tens of thousand ringed birds.
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