Zeeland covers 3117 km2, and is one of the least afforested provinces in The Netherlands (<1% woodland). The area has been subdivided in regions with a more or less similar landscape (Fig. 1). Five areas of 2250-9640 ha in size were chosen as monitoring plots (hatched in Fig. 1). Population densities of raptors are, except for Marsh Harrier, very low, mainly because of lack of suitable breeding sites. Nevertheless, numbers of Common Buzzard, Sparrowhawk and Hobby have increased 4-fold between 1991 and 1995 (Table 1). Marsh Harriers occur abundantly in creeks and overgrown marshland. Kestrels still largely depend on the supply of nestboxes. Nesting of Goshawk, Honey Buzzard and Peregrine has not yet been confirmed in Zeeland, but these species are increasingly observed in suitable breeding habitats. Some data on nestling production was collected on Marsh Harrier. Sparrowhawk, Common Buzzard and Kestrel (Table 2). Human persecution was apparently widespread (for further information on persecution, see Vergeer 1996).