Authors: Claire Buchan, Aldina M. A. Franco, Inês Catry, Anna Gamero, Alena Klvaňová, James J. Gilroy
Year: 2022
Publication: Global Ecology and Biogeography
Publication Link: https://onlinelibrary.wiley.com/doi/full/10.1111/geb.13551
Keywords: Afro-Palaearctic, anthropogenic change, breeding, hunting, migratory birds, non-breeding, threat mapping
Abstract:
Aim: Migratory species rely on multiple ranges across the annual cycle, rendering them vulnerable to a wide range of spatially disparate anthropogenic threats. The spatial distribution of these threats will strongly influence the magnitude of their population-scale effects, but this has not been quantitatively assessed for most species.
Location: Europe, Central Asia, Western Asia, Africa.
Time period: Modern.
Major taxa studied: Aves.
Methods: We combined remote-sensed data and expert opinion to map 16 anthropogenic threats relevant to migratory birds across Europe, Africa and the Middle East –including the first spatially-explicit pan-continental assessment of relative hunting pressure. By combining the resulting composite threat maps with species range polygons and morpho-behavioural traits-based
weightings (reflecting relative threat susceptibility), we created species-specific risk maps for 103 Afro-Palaearctic migratory birds breeding in Europe and evaluated how spatial threat vulnerability relates to long-term population trends.
Results: We found that greater vulnerability to direct mortality threats (including hunting pressure, infrastructure and nocturnal lights), especially in the non-breeding season, is associated with declining bird population trends.
Main conclusions: Our results emphasize the importance of spatially explicit approaches to quantifying anthropogenic drivers of population declines. Composite risk maps represent a valuable resource for spatial analyses of anthropogenic threats to migratory birds, allowing for targeted conservation actions.