In the eastern part of The Netherlands, including the adjacent Reichswald in Germany, Gerard Miiskens has been, and continues to do so, studying the breeding and feeding ecology of Goshawk Accipiter gentilis (which population increased from 4 breeding pairs in 1969 to some 30 in the late 2000s), Sparrowhawk A. nisus and Honey Buzzard Pernis apivorus since the late 1960s. This is one of the longest uninterrupted time series for raptor monitoring in The Netherlands.