Garrulus glandarius
Garrulus glandarius
This species has a wide distribution throughout the Palearctic, but is absent from treeless areas of the Asian steppes and plains, as well as from the Siberian boreal zones (BirdLife International, 2024). In Europe it is also absent from the far north of Fennoscandia (Keller et al., 2020). In Spain it is a typically Eurosiberian species, also occupying the Mediterranean region but in a more discontinuous manner (Arce in SEO/BirdLife, 2022). It occurs in habitats with extensive forest cover and is absent from treeless areas of the major river valleys of the Ebro, Duero, and Guadalquivir, as well as from the arid southeastern zones. Altitudinally, it is present from sea level up to the upper forest limit in mountain ranges.
In the province of Madrid it occupies the western half, with some isolated populations in the southeastern sector; always at mid and high altitudes in the mountains, inhabiting the forest ecosystems of slopes and foothills (Díaz et al., 1994).
In the national park its main areas of occupancy are the pine forests of the Fuenfría Valley and La Barranca in the south; the forests north of La Morcuera and in El Hoyo de San Blas in the central area; and in the north, the densely forested slopes south of the Navafría pass. It is always found in forest stands located in depressions and slopes with sufficient cover, and is absent from the summits.

It is a clearly forest-dwelling species that can occur in several types of woodland such as pine forests, oak woods or juniper stands, but it shows a preference for deciduous forests (Tellería et al., 1999), especially those dominated by oaks (Ramírez & Tellería, 2003). It favours dense forest patches, although it prefers edges and clearings.
In the national park it reaches its highest abundances within forested areas. It has been recorded at very low densities in shrublands and open habitats, likely during occasional movements or foraging bouts.

Globally, the species is assessed as Least Concern (LC; 2016). In Europe it is likewise classified as Least Concern (LC; 2020). In Spain, it is considered of Least Concern in the 2021 Red List.
The 1992 Catalogue of Threatened Species of the Community of Madrid does not assign this species to any threat category.
BirdLife International 2024. IUCN Red List for birds. https://datazone.birdlife.org.
Carrascal, L. M. y Díaz, L. 2003. Asociación entre distribución continental y regional. Análisis con la avifauna forestal y de medios arbolados de la península Ibérica. Graellsia, 59: 179-207.
Díaz, M., Martí, R., Gómez-Manzaneque, Á. y Sánchez, A. 1994. Atlas de las aves nidificantes en Madrid. Agencia de Medio Ambiente y SEO/BirdLife. Madrid.
Keller, V., Herrando, S., Voříšek, P., Franch, M., Kipson, M., Milanesi, P., Martí, D., Antón, M., Klvaňová, A., Kalyakin, M. V. Bauer, H. Gr y Foppen, R. P. B. 2020. European Breeding Bird Atlas 2: Distribution, Abundance and Change. European Birds Census Council y Lynx Edicions. Barcelona.
Ramírez, A. y Tellería, J. L. 2003. Efectos geográficos y ambientales sobre la distribución de las aves forestales ibéricas. Graellsia, 59: 219-231.
SEO/BirdLife (Molina, B., Nebreda, A., Muñoz, A. R., Seoane, J., Real, R., Bustamante, J. y Del Moral, J. C., Eds.). 2022. III Atlas de las aves en época de reproducción en España. SEO/BirdLife. Madrid.
Tellería, J. L., Asensio, B. y Díaz, M. 1999. Aves ibéricas. II-Paseriformes. J. M. Reyero Editor, Madrid.