Breeding is mainly confined to the Wadden Sea area (4100-5700 bp in 1998-2000, with largest concentrations along the mainland coast) and Delta area (2500-2900 bp, especially on artificial islands). More inland, numbers are highest in the west of the country and around Lake IJsselmeer. Large infrastructural works (Delta area) and, more recently, renaturation projects have been beneficial to the species. Quick response to new (though often temporary) habitats enabled the population to grow from 5000 bp in 1973-77 to 9000 in 1989, followed by some decrease to 7000 bp in the mid-1990s. In 1998-2000 numbers recovered to 7000-9000 bp.
- 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.