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The aim of this paper is to identify the habitat types listed in the Habitats Directive Annex I that require low-intensity agricultural management for their existence. We assessed the link between the Annex I habitat types and agricultural practices in order to identify habitat types that depend on the continuation of agricultural practices or whose existence is prolonged or spatially enlarged via blocking or reducing the secondary succession by agricultural activities. 63 habitat types that depend on or which can profit from agricultural activities-mainly grazing and mowing-were identified. They are classified into 2 groups: (1) habitats fully dependent on the continuation of agricultural management;(2) habitats partly dependent on the continuation of agricultural management. This paper also briefly discusses habitat types for which either doubts remain on their dependence on agricultural management, or the relation to extensive farming practices exists only in part of their area of distribution in Europe or under certain site conditions, respectively. Assessments of the conservation status of habitats of European Importance by 25 EU Member States in 2007 showed that habitats identified by us as depending on agricultural practices had a worse status than non-agricultural habitats.

In the second half of the 20 th Century there was a growing awareness of environmental problems, including the loss of species and habitats, resulting in many national and international initiatives, including the creation of organisations, such as the IUCN, treaties and conventions, such as Ramsar and the Berne Convention, and the establishment of networks of protected areas. Natura 2000 is a network of sites in the European Union for selected species and habitats listed in the 1979 Birds Directive and the 1992 Habitats Directive. Under the Habitats Directive a series of seminars and other meetings have been held with agreed criteria to ensure a coherent network. Despite both scientific and political difficulties the network is now nearing completion.

Setting aside protected areas is widely recognized as one of the most effective measures to prevent species from extinction. Accordingly, there has been a tremendous effort by governments worldwide to establish protected areas, resulting in over 100,000 sites, which are set aside, to achieve the 10% target proposed at the Fourth World Park Congress in 1992 in Caracas. The main effort of the European Union to achieve this target is the Natura 2000 network of protected areas, comprising over 25,000 sites representing 18% of the area of the 27 Member States of the European Union. The designation of Natura 2000 sites was based on species and habitats listed in the Annexes of the Habitats and Birds Directive. The effectiveness of the selection process and the resulting Natura 2000 network has often been questioned as each country made its designations largely independently and in most cases without considering the theories of optimal REsEARCH ARtiClE Launched to accelerate biodiversity conservation A peer-reviewed open-access journalBernd Gruber et al. / Nature Conservation 3: 45-63 (2012) 46 reserve site selection. However, the effectiveness of the selection process and the Natura 2000 network has never been explicitly analysed at the European scale. Here we present such an analysis focusing on the representation of Annex II species of the Habitats Directive in the Natura 2000 network relative to a random allocation of species to sites. Our results show that the network is effective in covering target species and minimizing the number of gap species (i.e. species not represented in a single site of the Natura 2000 network). We demonstrate that the representation is uneven among species. Some species are overrepresented and many species are only represented in a low number of sites. We show that this is mainly due to differing patterns in species ranges, as wide-spread species are inevitably represented in many sites, but narrow ranged species are often covered only by a small number of sites in a particular area. Finally, we propose a representation index that detects species that are underrepresented and could be used to direct future conservation efforts.

The EUNIS (European Union Nature Information System) habitat classification system aims to provide a common European reference set of habitat types within a hierarchical classification, and to cover all terrestrial, freshwater and marine habitats of Europe. The classification facilitates reporting of habitat data in a comparable manner, for use in nature conservation (e.g. inventories, monitoring and assessments), habitat mapping and environmental management. For the marine environment the importance of a univocal habitat classification system is confirmed by the fact that many European initiatives, aimed at marine mapping, assessment and reporting, are increasingly using EUNIS habitat categories and respective codes. For this reason substantial efforts have been made to include information on marine benthic habitats from different regions, aiming to provide a comprehensive geographical coverage of European seas. However, there still remain many concerns on its applicability as only a small fraction of Europe's seas are fully mapped and increasing knowledge and application raise further issues to be resolved. This paper presents an overview of the main discussion and conclusions of a workshop, organised by the MeshAtlantic project, focusing upon the experience in using the EUNIS habitats classification across different countries and seas, together with case studies. The aims of the meeting were to: (i) bring together scientists with experience in the use of the EUNIS marine classification and representatives from the European Environment Agency (EEA); (ii) agree on enhancements to EUNIS that ensure an improved representation of the European marine habitats; and (iii) establish practices that make marine habitat maps produced by scientists more consistent with the needs of managers and decision-makers. During the workshop challenges for the future development of EUNIS were identified, which have been classified into five categories: (1) structure and hierarchy; (2) biology; (3) terminology; (4) mapping; and (5) future development. The workshop ended with a declaration from the attendees, with recommendations to the EEA and European Topic Centre on Biological Diversity, to take into account the outputs of the workshop, which identify weaknesses in the current classification and include proposals for its modification, and to devise a process to further develop the marine component of the EUNIS habitat classification.