Breeding was reported from over 200 atlas squares, partly (64 squares) referring to immature non-breeders likely to start breeding in the near future. The largest numbers breed in the Delta area, where several colonies of over 100 bp occur and the total population was estimated at 520 bp in 2000. Elsewhere, scattered colonies are reported in coastal areas and along the rivers. The origin of the breeding population may be attributed to releases and escapes, in the Delta area perhaps also wounded wild birds. In 1998-2000 the national population was estimated at 750-1100 bp (first breeding record in 1984).
Meininger, P. L.
- 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.