In May 1992 European Union governments adopted legislation designed to protect the most seriously threatened habitats and species across Europe. This legislation is called the Habitats Directive and complements the Birds Directive adopted in 1979. The Birds Directive requires the establishment of Special Protection Areas (SPAs) for birds. SPAs help protect and manage areas that are important for rare and vulnerable birds because they use them for breeding, feeding, wintering or migration. The Habitats Directive similarly requires Special Areas of Conservation (SACs) to be designated for other species, and for habitats. SACs provide rare and vulnerable animals, plants and habitats with increased protection and management. Together, SPAs and SACs make up the Natura 2000 series.