The main breeding areas are situated in fens, former sewage works and other shallow waters in Drenthe and Noord-Brabant, in the northeast and south of the country; these account for over 50% of all occupied atlas squares and the bulk of the breeding pairs. Patchy occurrence elsewhere. Some atlas squares hold up to 80 bp, but such is untypical for the Dutch situation. Probably as a result of incursions from abroad, numbers and distribution have exploded since the 1970s and early 1980s. Marked annual fluctuations partly coincide with varying water tables. In 1998-2000 300-500 bp were recorded, the highest-ever numbers in The Netherlands (30-70 in 1973-77).
Seggelen, C. van
- SOVON Vogelonderzoek Nederland 2002. Atlas van de Nederlandse broedvogels 1998-2000. Nederlandse Fauna 5: 1-584. Nationaal Natuurhistorisch Museum Naturalis, KNNV Uitgeverij & European Invertebrate Survey-Nederland, Leiden.