Using distribution patterns of five threatened invertebrates in a highly fragmented dune landscape to develop a multispecies conservation approach D. Maes a, *, D. Bonte b a Division of Species Ecology and Populations, Research Institute for Nature and Forest, Kliniekstraat 25, B-1070 Brussels, Belgium b Ghent University, Department of Biology, Terrestrial Ecology Unit, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium ARTICLE INFO Article history: Received 27 March 2006 Received in revised form 26 July 2006 Accepted 13 August 2006 Keywords: Alopecosa fabrilis Belgium Conservation Dynamic grey dunes Spatial distribution Hipparchia semele Issoria lathonia Landscape effects Oedipoda caerulescens Xysticus sabulosus ABSTRACT We analysed the patterns of occupancy of five threatened invertebrates in a highly frag- mented dynamic grey dune landscape. During two years (2003–2004), 133 dune patches between Nieuwpoort (Belgium) and Bray-Dunes (France) varying in area, connectivity, eolian sand dynamics and trampling disturbance were sampled for five focal species: two spiders (Alopecosa fabrilis and Xysticus sabulosus), two butterflies (Issoria lathonia and Hipparchia semele) and one grasshopper (Oedipoda caerulescens). Overall diversity was highest in large and well connected patches that were characterised by high eolian sand dynamics and an intermediate trampling intensity. Patch occupancy differed greatly among species: all species significantly occurred more often in large and connected patches. High tram- pling intensity (by cattle and/or tourists) negatively affected the two ground dwelling spi- ders, but not the grasshopper or the butterfly species. High eolian sand dynamics positively affected the presence of the spider X. sabulosus, the grasshopper O. caerulescens and the butterfly H. semele, but had no significant effect on both other species. Colonisation was mainly explained by connectivity and never by patch area, while extinction events in H. semele were explained by small patch area. We discuss the implications of using a suite of focal species for management and restoration purposes in the highly fragmented dune area in Belgium and we promote the use of a multispecies approach for evaluating and monitoring conservation efforts in general. Ó 2006 Elsevier Ltd. All rights reserved. 1. Introduction Nature conservation in many countries is largely biotope- and/or ecosystem-based, i.e., sites are acquired and/or man- aged for the presence of threatened biotope types (e.g., Annex I of the European Union Habitat Directive) or in function of ecological processes (e.g., nutrient cycles, hydrology) respec- tively. But, several authors have shown that species can go ex- tinct under such site- or ecosystem-based conservation policies (Pickett et al., 1992; Simberloff, 1998). The incorpora- tion of species into decisions about site selection or manage- ment measures is, up to date, rather scarce, especially in Flanders (north Belgium – Maes and Van Dyck, 2005). The necessity and complementary nature of both species and eco- system conservation simultaneously, however, can render nature conservation considerably more efficient through the 0006-3207/$ - see front matter Ó 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.biocon.2006.08.001 * Corresponding author: Tel.: +32 2 558 18 37; fax: +32 2 558 18 05. E-mail addresses: dirk.maes@inbo.be (D. Maes), dries.bonte@ugent.be (D. Bonte). BIOLOGICAL CONSERVATION xxx (2006) xxx – xxx available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/biocon Please cite this article as: D. Maes, D. Bonte, Using distribution patterns of five threatened invertebrates..., Biological conservation (2006), doi:10.1016/j.biocon.2006.08.001 ARTICLE IN PRESS