Ecological Succession of Breeding Bird Communities in Deciduous and Coniferous Forests in the Sopron Mountains, Hungary

Abstract

The relationship between breeding bird communities and different phases of secondary succession of deciduous (sessile oak – Quercus petraea) and coniferous (spruce – Picea abies) forests in the Sopron Mountains was studied. The bird censi have been carried out in 5 different successional stages using the “double-visit fixed-radius point count technique”. A total of 38 bird species were encountered. There are typical bird communities to order to different stages of forest succession, containing unique bird species or species appearing predominantly in that successional stage. The study has shown structural changes in breeding bird communities during the succession. Bird species richness, density and diversity showed the same trends. Their numerical values were the lowest in the clear-cut areas with young (1-2 year old) plantations, and the highest in the mature stands. After a starting increase (shrub stage) there is a slight decline (10-12 year old stands) because of the canopy closure of the young trees. Further decrease can be observed in the low pole stands, as these habitats are no longer appropriate for species nesting in shrubs and not yet suitable for the hole-nesting ones. Species richness, density and diversity were lower in early pole and older spruce stands than in the corresponding oak stands.