Atlas of Birds during the Breeding Season in the Sierra de Guadarrama National Park

Knowing the distribution of species within a specific period of time and in a natural area is a basic requirement for determining the conservation status of that area’s biodiversity. This type of work makes it possible to establish current distribution ranges and to provide the baseline against which potential future changes can be compared. Furthermore, the information generated helps identify priority areas for conservation within the study area, based on the location of threatened species, particularly high densities of certain species, specific richness in particular zones, and other relevant factors.

Royal Decree 18/2020, of 11 February, issued by the Governing Council, approved the Master Plan for Use and Management of the Sierra de Guadarrama National Park within the territorial scope of the Community of Madrid. The protected area covers 33,960 hectares belonging to the autonomous communities of Madrid (21,714 hectares) and Castile and León (12,246 hectares). Since the ordinary and routine management of this area corresponds to both autonomous communities within their respective territories, information relating to the National Park within the Community of Madrid is essential to ensure proper management.

Article 16 of this Plan, in section 2, states the need for “Conservation activities to give preferential attention to the habitats and species identified as priority conservation values.” Section 3 adds that “Conservation actions shall be undertaken for threatened native species, especially endemic ones.” These two points make it necessary to have a complete inventory of the birds of the National Park and the location of each species.

The same Royal Decree, in Article 21, Criteria relating to research, establishes the need to create inventories in order to facilitate the management of the protected area:

• Research shall be encouraged both through the resources of the managing authority and through collaboration with various scientific and educational institutions.
• Priority shall be given to research aimed at solving management problems.
• In general, the information and data resulting from the research carried out in the national park must be made public, except for those whose disclosure may compromise the conservation of certain values or species of the National Park.

These principles are fulfilled in the section corresponding to the inventory of birds during the breeding season in the Madrid sector of the National Park, and they contribute to the objectives established by Royal Decree 18/2020.

The number of bird species present in a given area during what is considered the breeding season may be larger than the number of species actually breeding at that time, since birds form a very large taxonomic group with great mobility and migratory behaviour. Therefore, this inventory is partial, although it covers one of the most important phases of the species’ biological cycle: reproduction. The breeding period is a critical time for all species, as their success largely determines their survival and generational replacement. This period is equally important for those birds that do not use the territory for breeding but do use it as a resting or feeding area; thus, the area is essential for their conservation. For this reason, the conditions of the place where birds are found at a given moment directly influence their survival, as these conditions are necessary for reproduction, feeding, resting, and development.