Habitat loss and disturbance pose great threats to wildlife, and these may be particularly severe for migratory birds. A well-connected network of foraging, resting, breeding, and moulting sites is essential for bird migration. However, losing a key site can breakdown a bird migration network completely, and consequently trigger population decline. Yanjie Xu monitored the changes in the connectivity of these bird migration networks in the past decades. Moreover, she pointed out the consequences of connectivity loss in bird migration networks. These consequences include population declines in birds, changing disease risks, etc. To protect bird migration networks from connectivity loss, she proposed a network approach to prioritizing conservation efforts of sites. Her findings give novel insights into the impact of global change on wildlife, and can facilitate systematic conservation policy making for migratory species.