Changes in vegetation and post-breeding habitat-related distribution of passerines in western Hungary

Abstract Studying habitat selection in birds provides important insights into how different habitat types influence survival. However, knowledge of the habitat-related distribution of birds during the post-breeding period and its relationship with vegetation structure remains incomplete. This study was conducted at an approximately 15 ha resting, feeding and shelter site in western Hungary during the post-breeding seasons between 2001 and 2024. Fifty commonly occurring passerine species were selected to examine their distribution across habitat types and how this distribution changes in response to vegetation dynamics. In total, 129,952 individuals representing 50 species were captured and ringed. Willow stands and other woody vegetation were delineated as polygons on georeferenced orthophotos, and their spatial extent was quantified for each study year. Based on capture rates, bird species were unevenly distributed among the four habitat types. Canonical Correspondence Analysis (CCA) indicated that vegetation physiognomy and coverage were the primary factors shaping the habitat-related distribution of birds. Habitat–period model analyses revealed temporal changes in habitat associations, which were consistent with the long-term development of vegetation structure at the study site. Species associated with dense shrub vegetation (e.g. Eurasian bullfinch Pyrrhula pyrrhula , common firecrest Regulus ignicapilla ) or forest habitats (e.g. wood warbler Phylloscopus sibilatrix , European pied flycatcher Ficedula hypoleuca ) showed increasing relative capture probabilities in swamp habitat over the study period. In contrast, species typically associated with open habitats (e.g. red-backed shrike Lanius collurio , whinchat Saxicola rubetra ) showed decreasing associations with swamp habitat. These results indicate temporal shifts in habitat use among passerine species during the post-breeding period and highlight the importance of maintaining habitat heterogeneity in post-breeding areas.