Strong Decline in Breeding-Bird Community Abundance Throughout Habitats in the Azov Region (Southeastern Ukraine) Linked to Land-Use Intensification and Climate

Abstract

In recent decades, bird communities associated with agricultural systems have declined in Western and Central Europe and in North America, but how widely these dynamics extend to other regions is poorly known. In this study, we assessed the dynamics and the main drivers of the changes in the abundance, richness, and composition of breeding bird communities over a 30-year period in the various types of habitats of southeastern Ukraine (Azov region), a region that has undergone agricultural intensification for several decades. This study was conducted in the valley of the Molochna River during the 1988 to 2018 nesting seasons. The area studied hosted 81 bird species. Species richness varied from three species in salt marshes to thirty-three in reed beds but did not show a general trend over time. However, we identified a decline in bird communities’ total abundance over time in all habitats except shelterbelts and meadows. Similarly, species composition changed over time, reflecting the way in which species varied in their abundance changes. Climatic variables contributed to bird community turnover, but with decreasing importance over time. Overall, our results indicate that the recent declines in bird populations in farmland regions also extend to eastern Europe, with land-use effects interacting with climate to shape temporal dynamics of bird communities.