Popis: |
Anthropogenic changes in forest structure threats the persistence of numerous organisms. In Spain, Pyrenean oak (Quercus pyrenaica) forests are mainly subjected to three sylvopastoral management systems which determine variations in the forest structure: (i) ‘‘young forests’’ subjected to frequent disturbance by fires and clear-cuttings; (ii) ‘‘Pyrenean oak dehesas’’, subjected to a traditional sylvopastoral system exclusive to Spain which favours the development of both old oaks and pasture; (iii) largely undisturbed ‘‘mature forests’’. We examined the effects of these sylvopastoral management systems on habitat use and reproduction of the middle spotted woodpecker (Dendrocopos medius), a forest specialist bird, at the south-western edge of its distribution range. Habitat use was examined at multiple spatial scales. Within the territories, woodpeckers preferred large diameter oaks for foraging and decay oaks with holes for nesting. Within the forest tracts, no significant relationships between territory density and habitat structure in the forest tracts were found. At the landscape scale, dehesas and mature forests, both with high densities of important foraging and nesting trees, were occupied by woodpeckers. Young forests, with low densities of those trees, were avoided. No significant differences in territory density or reproductive success were found between dehesas and mature forests. The maintenance of viable woodpecker populations requires conservation actions at several spatial scales. Within the forest tracts, suitable densities of important foraging and nesting trees must be maintained. At the landscape scale, management decisions must consider the maintenance of traditional sylvopastoral systems in dehesas and mature forests. At the regional scale, taking into account a habitat cover in the landscape of the 7% for the Cantabrian Mountains, we estimated an area of 285,000 ha to be included in the conservation planning unit for the middle spotted woodpecker. # 2007 Elsevier B.V. All rights reserved. |