Voedselonderzoek 1984-1988 Haviken in Zuid-Twente I

From 1984 up to and including 1988 FT. Koopmans and I made a study of Goshawk predation and for that we visited a part of the research-area twice a week. This area measures about 36 square kilometres in the Dutch municipalities of Haaksbergen and Enschede and, in neighbouring Ahaus and Borken in the F.R. Germany. Information was mainly obtained by kills found by searching, partly by pellets study and for a very small part by direct observations. 757 prey remains have been classified into a total of 36 bird species and 4 mammal species. The principal prey is the Domestic Pigeon (Columba livia) at 39%, second the Woodpigeon (Columba palumbus) at 22%, Corvidae at 13% and other species at 26%. For part of their food choice Goshawks are focused on preys of opportunity. For the entire period of five years you may deduce in the whole area the bond of Goshawks with theirs home range from the amount of kills found monthly. The more Goshawks there are in the area, the more prey remains you will find. By itself the amount of kills found yearly forms no reliable indication of the number of Goshawks in a home range.