Microgeographic variation in citril finch Carduelis citrinella abundance as a consequence of resource availability and ancient landscape cultivation

The avifauna of mid-European mountains has for a long time been influenced by the intensive activities of man. As a consequence, the ancient cultivation in the formerly wooded Black Forest has led to a typical semi-open to open cultural landscape (heath land) on the mountain summits dominated by extensive pasturing with cattle and goat. Within several species of semi-open landscapes, especially citril finches profited from this development. However, during the last decades pasturing and transhumance activities ceased drastically, and continuous natural and artificial reforestation began. Due to these changes, several characteristic bird species of this semi-open landscape decreased strongly or became extinct. In this thematical context I studied microgeographic habitat selection in citril finches as a consequence of resource availability at mount Schliffkopf in the Northern Black Forest. As expected, citril finches are especially drawn to man-made habitat structures in this area and seem to react directly to the continuous reduction of these structures in the last centuries. Its recently observed population decline is characteristic for a couple of other bird species of semi-open landscapes in mid-European mountains, such as woodlarks and nightjars.[PUBLICATION ABSTRACT]