Resumen de Cambios a largo plazo en las comunidades de aves reproductoras de dos bosques del noroeste de España
Ignacio Munilla Rumbao, José Vicente López Bao, Juan P. González Varo, José Guitián Rivera
Here we document long-term changes (1977-2004) occurred in the bird assemblages of two woodland patches in relation to the pattern of change in land use and bird populations at the landscape level. The patches selected are representative of the main forest ecosystems in the area: mixed deciduous and chestnut woodland. The study was conducted in Caurel (Galicia, NW Spain), a mountain area that is under a swift process of land abandonment. Land use changes were assessed by means of the 1978 and 2006 vegetation maps. Changes in the avifauna at the landscape level were assessed by comparing two intensive bird surveys conducted in 1977 and 2000. Bird assemblages in the two woodland patches were censused using exactly the same transects in 1977, 1999 and 2004. The largest percent change in vegetation was evident in total woodland area (+34 %). Changes in bird populations at the landscape level were consistent with changes in vegetation, thus favouring woodland/high scrub species. However, local bird assemblages in the woodland patches appeared to remain stable in species richness, composition and structure throughout the 27 years of the study. We suggest that the little long-term variability exhibited by these bird assemblages could be related to habitat stability in the woodland patches.
