Abstract:
The migration patterns of migratory birds are governed by a complex interplay of species biological traits and environmental factors. A thorough understanding of these patterns is not only fundamental to avian ecology but also a critical prerequisite for effective conservation planning. Poyang Lake, the largest freshwater lake in China, serves as a vital wintering site for hundreds of thousands of migratory waterbirds and, importantly, operates as a key rescue and rehabilitation station for injured or debilitated individuals. Rescued birds that are successfully released back into the wild provide a unique opportunity to examine whether human intervention disrupts natural migratory behaviour, a question of both practical and theoretical significance. To investigate the migration patterns of rescued
Anser albifrons after their release back into the wild at Poyang Lake, 12 rescued individuals were tracked using satellite tracking devices and their movements were continuously tracked during both spring and autumn migration seasons over multiple years. The tracking data revealed that the overall migration routes of these rescued
A. albifrons remained consistent with those documented for wild populations, indicating no major behavioural alteration attributable to the rescue process. The migration route roughly followed: passing through Jiangxi, Anhui, Jiangsu, and Shandong, crossing the Bohai Sea, then through Liaoning, Jilin, and Heilongjiang to reach the junction area of Inner Mongolia, Jilin, and Heilongjiang for stopover; thereafter, they continued northward through Inner Mongolia and Heilongjiang, entered Russia via its southern border, and then followed the Lena River to reach breeding grounds in northern Russia near the Arctic Ocean. The spring migration of the rescued
A. albifrons began mainly in late March and ended from April to June. The duration of spring migration varied considerably among individuals, with the shortest being only 21 days and the longest up to 91 days. Autumn migration started between September and October and ended between October and December, also showing large individual variation, ranging from 20 to 74 days. The stopover sites of the
A. albifrons were mainly concentrated near reservoirs, ponds, and tidal flats, and the number of stopovers during spring migration was significantly higher than that during autumn. For
A. albifrons breeding in northern Russia, the spring migration distance ranged from 5 441.69 to 6 182.71 km, with an average migration speed of (22.89±6.12) km/h and a maximum instantaneous speed of 130.40 km/h. The autumn migration distance ranged from 5 226.48 to 6 348.17 km, with an average speed of (37.22±9.75) km/h and a maximum instantaneous speed of 132.40 km/h. The
A. albifrons is one of China’s important migratory birds. Conducting proper rescue operations for this species does not significantly affect its migration patterns, further supporting the necessity of routine rescue efforts along migratory flyways.