E. COSYNS*, A. DELPORTE*, L. LENS† and M. HOFFMANN*‡ * Department of Biology, Terrestrial Ecology Unit, Ghent University, Krijgslaan 281 – S8, Ghent, Belgium, † Department of Biology, Terrestrial Ecology Unit, Ghent University, Ledeganckstraat 35, B-9000 Ghent, Belgium, and ‡ Institute of Nature Conservation, Section Landscape Ecology and Nature Management, Kliniekstraat 25, B-1070 Brussels, Be...