It was confirmed that in the north of Poland winged specimens of Myzus persicae (Sulz.) start to migrate in spring approximately over three weeks later than in the central and sou them regions. It was observed that during the 1981-1990 and 1991-2000 decades, M. persicae started its flights approximately over two weeks earlier than during the 1971-1980 decade. With this respect one may conclude that the changes are permanent. There were also changes in quantity. In some places the M. persicae share in the entire aphid fauna on potato crops was observed to have decreased as the time passed, which, as it seems, may be associated with a decrease in potato crops area in Poland. Such a correlation can also be confirmed by the fact that in the area where M. persicae share increased, the potato crops area also increased extensively.