© 2016 Los Autores. The abandonment of traditional farmland practices in the mountain areas of the Mediterranean Basin is producing a general vegetation encroachment and a decrease on open habitats. The protected mountain areas of the LTER (Long Term Ecological Research) network are privileged zones to study in detail this process by means of long-term monitoring projects. In the particular case of the nodule LTER Montseny the impact of afforestation on birds is been monitorised during more than a decade in the framework of the Catalan Common Bird Survey. This scheme has allowed developing indicators that determine the shifts in bird communities associated to the open and forest habitats of this natural park. In this work we used multispecies indicators based on the geometric means of yearly population indices to determine the change that, as a whole, the birds are undergoing in these environments. Results show that the impact of vegetation encroachment is noticeable in the populations of open-space species (44% population decrease between 2002 and 2014). Following these results, park managers, together with local socioeconomic stakeholders, are promoting practices to recover and improve open pastures.
- Natural parks
- Open habitats