Helminths in migrating and wintering birds recorded in Poland.

Among 544 species of helminths recorded in birds on the territory of Poland, probably some (17 species of Digenea, 21 Cestoda, 13 Nematoda and 5 Acanthocephala) do not belong to the native fauna. These are helminths obtained in mature stage from birds shortly after their arrival from wintering grounds, or from foreign populations wintering with us, or being in the course of spring or autumn migration through the area of our country. In general, these helminth species have been recorded sporadically in the examined birds.