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The importance of extensively managed grasslands and protected areas for a flagship steppe bird, the Little Bustard Tetrax tetrax, on a Mediterranean island
Published online by Cambridge University Press: 15 December 2025
Summary
The Little Bustard Tetrax tetrax has experienced steep population declines across its range, with Sardinia now hosting the last remaining Italian population and the only island population worldwide. We conducted a systematic island-wide survey in 2023, based on 969 point-count data, analysed through robust distance sampling, to assess population density, spatial distribution, habitat associations, and the role of protected areas. We estimated a total density of 0.89 males/km², with 85% of individuals concentrated in two highland subpopulations, i.e. Ozieri and Abbasanta. Highest densities occurred in hay meadows and heterogeneous landscapes, while arable and fallow lands supported lower densities. Protected areas hosted five times higher densities of Little Bustard than unprotected land. Land-use changes over the past 13 years and current soil degradation showed no significant association with current densities, suggesting that declines may be linked to earlier landscape transformations. Our results underscore the critical importance of protected areas and traditional agropastoral systems for the conservation of the Little Bustard in Sardinia. Urgent conservation planning is needed to maintain existing habitats and mitigate emerging threats from land-use change and infrastructure expansion.
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- © The Author(s), 2025. Published by Cambridge University Press on behalf of BirdLife International
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Santangeli et al. supplementary material
Santangeli et al. supplementary material
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