Background and context

Over the last 60 years, there has been a major reduction in the extent of semi-natural habitat and in the populations of many species of plants and animals in the United Kingdom as a result primarily of: the intensification of agriculture, the commercialisation of forestry, the expansion of urban areas and transport infrastructure, air pollution and the nutrient enrichment of many of the rivers and lakes.  Many of the same pressures have been experienced in other parts of Europe.
Over the same period, the UK has taken conservation action to mitigate this general decline in biodiversity through the establishment of a substantial network of protected areas, and has brought in measures to protect species populations from unsustainable exploitation. The resources available to underpin and support this effort over much of this period have been limited, but over the last 15 years or so resources have been significantly increased and legal protection enhanced.  In addition, action has been taken, in response to the UK's international obligations under the United Kingdom Biodiversity Action Plan, to support the recovery of many of the habitats and species which were, nationally, under most threat.
The UK's protected areas programme includes work to identify, protect and conserve National Nature Reserves, Sites of Special Scientific Interest (Areas of Special Scientific Interest in Northern Ireland) and other protected wildlife areas. The United Kingdom has instituted a monitoring programme using common standards to assess the condition of these protected areas. The report on the first six-year round of this monitoring was published by JNCC in 2006.
Recognising the declines in biodiversity which had taken place in the latter part of the 20th century throughout Europe, the European Community, in the late 1980s and early 1990s, identified habitats and species considered to be under threat within the areas of the Community as a whole.  In 1994, the EC Habitats Directive came into force.  It requires Member States to take conservation measures in relation to these threatened habitats and species, to undertake surveillance in relation to them, and, every six years, to report on the outcome of these measures on their conservation status.  For some of the listed habitats and species, the Directive requires Member States to designate Special Areas of Conservation (SACs).  For some of the listed species, the Directive does not require SACs to be established, but requires Member States to take other measures.
The United Kingdom has designated the network of Special Areas of Conservation required by the Habitats Directive, adding them to its existing protected sites network. These sites, together with Special Protection Areas classified under the EC Birds Directive, form the network of European sites known as Natura 2000. Most of these sites are supported by being also designated as Sites of Special Scientific Interest. The United Kingdom has also implemented the species protection measures required by the Directive.
The Habitats Directive defines when the conservation status of the habitats and species it lists is to be considered as favourable.  The definitions it uses for this are specific to the Directive; in summary, they require that the range and areas of the listed habitats, and the range and population of the listed species, should be at least maintained at their status when the Directive came into force in 1994 or, where the 1994 status was not viable in the long term, to be restored to a position where it would be viable.  The habitats and species were listed in the Directive because they were considered to be under threat in the European Community as a whole, it is to be expected that, prior to the Directive coming into force in 1994, their conservation status would be unfavourable.  The six-yearly reports required by the Habitats Directive are intended to track improvement in the conservation status of these habitats and species since that time.

Links to further information