Species-specific responses to habitat and livestock management call for carefully targeted conservation strategies for declining meadow birds

Abstract

In recent decades, upland hay-meadows underwent large transformations due to the modernization of livestock husbandry system. Such changes impacted on biodiversity, but their consequences on the upper levels of the food web (e.g. birds) are largely unknown. Grassland specialists could respond differently to landscape structure and management practices, and such potentially different responses should be integrated into conservation and management strategies.To elucidate the effect of meadow characteristics on avian grassland specialists, we considered three declining bird species regularly found in European meadowlands.We compared their mean densities at 63 landscape plots in the Italian Alps with that reported from other studies and analysed their environmental preferences in relation to landscape (composition and structural elements), management (meadow fertilization and mowing calendar), topographic (slope and elevation), and spatial predictors. Shedding light on their ecological requirements, we identify possible causes of long-term decline as well as conservation strategies for grassland specialists.Mean territory density of ground-nesting species (whinchat, 0.75 territory/10 ha, and tree pipit, 0.42 territory/10 ha) resulted lower than most other estimates obtained in the Alps; conversely, the density of the shrub-nesting red-backed shrike (1.97 territory/10 ha) was comparable to that of many other Alpine areas. Meadow conversion into other crops and the modern livestock husbandry (i.e. first mowing performed before the end of the third week of June, made possible by meadow overfertilization) have likely contributed to regional depletion of whinchat and tree pipit populations, especially below 900–1000 m asl.Heterogeneous landscapes dominated by grassland, with large extents of unimproved meadows, close to meadows interspersed with isolated trees, hedgerows and ecotones, could accommodate the ecological preferences of multiple grassland specialists. As such landscapes have become increasingly rarer, the remaining ones must be preserved via integrated plans for sustainable mountain development.