SCHIPPER W (1973) On the occurrence of harriers in Flevoland in 1971 and 1972. LIMOSA 46 (1): 67-71.

During a study of harrier biology in the still partly reed-covered reclaimed areas of Zuidelijk and Oostelijk Flevoland, the total number of nests was estimated. (Table 1). Flevoland appeared to contain an important part of the total Dutch harrier populations, while the occurrence of three harrier species, regularly breeding together in one area is unique in Western Europe at the moment. In winter the harrier summer populations make place for many Hen Harriers, which stay the night in several communal roosts, scattered over the area (Table 2). As progress of cultivation of the area goes with loss of reed-covered surface, future developments are briefly discussed. Hen Harrier Circus cyaneus Montagu's Harrier Circus pygargus Western Marsh Harrier Circus aeruginosus

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