SEASONAL-CHANGES IN BIRD COMMUNITIES OF C ULTIVATED WETLANDS IN SCHLESWIG-HOLSTEIN GERMANY/

The number of bird species and individuals were determined in 2 study plots (total 6,8 km(2) and 105 counts) in cultivated lowlands (grassla nd) of Schleswig-Holstein during 1976-1984. In order to estimate the t otal population of selected species additional comparison sites were s urveyed. In total up to 219 km(2) (up to 1993) were surveyed. The aver age number of species observed each year was 37,4. On average 28% of t he birds recorded each year were breeding species and 72% were non-bre eders (of these 36% were breeding birds of the surrounding villages an d woods and 36% were migrants and visitors). The average abundance was 48,1 individuals/10 ha. An almost complete exchange of non-breeders a nd local breeding birds occurs once a year. Estimated population sizes of dominant and characteristic species in Schleswig-Holstein are pres ented. Some lowland sites are very attractive habitats of internationa l importance especially during the winter.