Natura 2000 sites can vary considerably in character. They are not strictly protected in terms of how they are allowed to be used by people. Many sites are farmed, forested and some are even in urban areas. Other areas are much wilder. The European Commission developed guidelines on the relation between Natura 2000 and wild areas which are thought to make up around 13% of the network. This was in response to a report by Members of the European Parliament in 2009 which called for further protection of Europe's wilderness.