Over 30 years decline of an iconic farmland bird, Red-backed Shrike <i>Lanius collurio</i> , in a Central European stronghold: meadow loss and shrub succession drive near-local extinction

Summary Agricultural intensification has profoundly transformed Europe’s landscapes, driving widespread declines in farmland bird populations. Among the most pressing threats is the loss of meadows, either through conversion to arable land as a result of intensification, or through agropastoral abandonment leading to shrub encroachment. Although farmland bird populations in Central and Eastern Europe have historically declined more slowly than in other regions, recent evidence shows that even once-common species are now in decline. This highlights the urgent need to quantify these trends and identify their underlying drivers. In this study, we investigate habitat preferences and factors underlying the severe, over 30-year decline of Red-backed Shrike Lanius collurio , an iconic farmland species and key bioindicator of grassland biodiversity. Our research focused on a 440-ha alluvial floodplain in Slovenia’s Sub-Pannonian region, a site considered a national stronghold for the species. Territory surveys were conducted intermittently from 1992 to 2025, with detailed habitat mapping available from 2004 to 2022. Consistent with previous studies, our results indicated that breeding Red-backed Shrikes primarily occupied ecotonal habitats marked by extensive meadow cover, moderate shrub density, and high habitat heterogeneity. Alarmingly, between 1992 and 2025, the population declined by 92.44%, decreasing from 172 territories to just 13. The steep decline observed was likely driven by agricultural intensification, persisting under the Common Agricultural Policy (CAP), with conversion of meadows into arable land and the loss of traditional management leading to shrub encroachment. The latter emerged as the strongest predictor of population decline in the most recent years. Our findings emphasise the urgent need to protect, manage, and restore meadows to prevent further biodiversity loss. Considering the relatively better historical status of farmland bird populations in Central and Eastern Europe compared with their Western European counterparts, this worrying trend indicates that similar declines are likely widespread, highlighting the need for immediate research and targeted conservation efforts.