Differences in network structure and connectivity of four (protected) Palearctic-Afrotropical flyways

Aim – Waterbirds that travel seasonally between Europe and Africa use wetlands along four major Palearctic-Afrotropical flyways. However, it is unknown to what extent the overall connectivity of these flyways may be threatened by ongoing habitat loss and degradation. Here, we contrasted the wetland connectivity along these four flyways, applying graph-theoretic connectivity metrics on an intercontinental scale. We also explored for which flyway connectivity is most at risk. We then identified the most important wetlands by their contribution to connectivity in each flyway. Location – Western Palearctic, Afrotropics Methods – Based on high-resolution wetland maps, we calculated directional probabilistic connectivity metrics. Estimates of overall connectivity of each flyway were obtained, as well as the relative importance of wetlands, for birds with different migration strategies: short-distance hoppers and long-distance jumpers. Results – The East-Atlantic flyway and Eastern Mediterran...