Many of our most important places for wildlife are now protected as Sites of Special Scientific Interest (Areas of Special Scientific Interest in Northern Ireland). The legislation under which they are notified and managed varies by country.
A few hundred sites have been carefully selected to form part of a developing EU-wide network of internationally important protected sites, known as Natura 2000.
The network includes sites of international importance for birds designated under the EU Birds Directive, and for other habitats and species under the EU Habitats and Species Directive. Developments which would destroy or harm a Natura 2000 site will only be permitted if the proposer can show need and there is no alternative, and the government decides it is necessary because it is in the over-riding public interest that it should proceed. Any loss must be compensated for through the creation of new habitat.
In England, the Birds and Habitats Directives are implemented through the 1994 Conservation (Natural Habitats &c.) Regulations
In addition, some of the most important wetland sites are protected under the Convention on Wetlands of International Importance as 'Ramsar' sites (named after the town in Iran where the Convention was agreed).
Of course, not all species and habitats can be protected through these national and international designations alone. There are many places of county and local significance which must be conserved if the overall quality of wildlife is not to be eroded.
Some species, such as the skylark, are widespread and currently occur in large numbers, but are in steep decline. Site protection is not very effective at aiding the conservation of dispersed, but threatened, species of this kind: policy initiatives to create a more environmentally friendly farming system are likely to be more effective.