Council Directive 92/43/EEC adopted on 21 May 1992 aims to promote the maintenance of biodiversity through the conservation of natural habitats and of wild fauna and flora on the European territory of the Member States. A coherent European ecological network of special areas of conservation will be set up under the title "Natura 2000". The network will be composed of sites (proposed by the Member States) hosting certain types of habitat or specific species' habitats to be restored to a favourable conservation status in their natural range and will include the special protection areas classified by the Member States pursuant to Directive 79/409/EEC. Each Member State will contribute to Natura 2000 in proportion to the representation within its territory of the designated habitats, details of which are provided in annexes to the new Directive. Once a site has been officially approved by the Commission, the Member State shall designate it as a special area of conservation within six years at most and establish priorities for its maintenance or restoration. On the basis of estimates submitted by the Member State, the Commission shall adopt under the relevant Community instruments a prioritized framework of measures for co-financing the required actions. Member States and the Commission shall encourage the necessary research and scientific work having regard to the general objectives and obligations of the programme and they shall, to this end, exchange information. Particular attention is to be paid to scientific work in the fields of ecological coherence and land management as well as to the broader subjects of biogeography and biodiversity in the Community.