CHANGES IN THE BREEDING DISTRIBUTION AND FREQUENCY OF THE GREYLAG GOOSE (ANSER-ANSER) IN SOUTHERN MORAVIA

In 1980-82 and 1990 we determined the number of greylag geese (Anser anser) breeding in southern Moravia (Czech and Slovak Federative Republic). An increase in the number of breeding pairs after 1940 continued up to a maximum number of 297 pairs in 1982, in 1990 there were 281 breeding pairs. After 1940 the number of breeding places increased; after water-system regulations carried out in the study region their number decreased from a maximum of 56 registered in 1968 to 37 in 1990. Within one year, however, the maximum number of breeding places occupied was 27. Decrease in the number of breeding places results in the concentration of a higher number of pairs in fewer places: the nesting of individual pairs (25.6 % of breeding places) is always irregular, 42.3 % of the breeding places were occupied by more than 5 pairs. The highest number of 173 nests was registered in 1990 at the Nove Mlyny Middle Reservoir.