Abstract: Over the past few decades, the populations of many bird species along the East Asian-Australasian Flyway have shown a trend of decline. In this study, we investigated whether changes in the diversity and population of migratory birds were detectable at a key stopover site on the East Asian Flyway, Qinhuangdao Bird Banding Station, Hebei Province, China, based on bird-banding data collected between 2004 and 2020. During the 17-year period, a total of 209393 birds of 225 species were banded. Among these birds, there were 15642 individuals (7.5% of the total) representing 29 national key protected species (12.9% of the total banded species). The Shannon diversity index showed a significant trend of decrease, while the evenness index and dominance index remained unchanged, indicating that a reduction in species richness was the main cause of the decline in diversity. An analysis of the two predominant national key protected species banded, i.e., the Siberian Rubythroat (Calliope calliope) and the Chestnut-flanked White-eye (Zosterops erythropleurus), revealed that their numbers stopping over at Qinhuangdao were relatively stable. Both species showed significantly different migration process between spring and autumn, with the spring migration being much faster and more concentrated. Over the 17 years, there was no effect of temperature on spring migration phenology in both species. The decline in the diversity of banded birds in Qinhuangdao is, on one hand, a result of the overall changes in bird communities along the flyway, and on the other hand, may be related to the decrease in net capture rates caused by vegetation growth at the netting sites. Appropriate thinning and canopy pruning of vegetation at the netting sites should be carried out in the future to maintain the structural heterogeneity of the shrub-arbor ecotone, thereby providing suitable habitats for a variety of bird species.

Key words: bird banding, migration timing, East Asian-Australasian Flyway, stopover site