Abstract: The survey of population size and distribution is fundamental for population dynamics research, and is also key to determining and understanding the threats to various species. As an important migration corridor and breeding site for migratory waterbirds in northeast Asia, Xingkai Lake in Heilongjiang Province is a significant wetland for the conservation of Oriental Storks (Ciconia boyciana). In this study, we analyzed changes of stork population abundance at Xingkai Lake in the migration and breeding seasons from 2002 to 2018, and examined the effects of the reintroduction of artificial nests on stork population dynamics and the driving factors. Our results showed that the number of storks increased significantly in spring  (R²=0.641, P=0.000) and the breeding season (R²=0.866, P=0.000), and that in autumn fluctuated greatly among different years. There was a significant positive correlation between the numbers of storks in spring and summer (R=0.701,P=0.002), indicating that the high population number in spring resulted in high number in summer. The nests of Oriental Storks at Xingkai Lake were mainly distributed in Longwang Temple (84.16%), Dongbei Paozi (12.87%), oxidation pond (1.98%) and Qing-shan Reservoir (0.99%). From 2002 to 2018, the number of successful nests, including natural (R²=0.514, P=0.001) and artificial nests (R²=0.823, P=0.000), significantly increased. The increases in stork population number at Xingkai Lake were mainly affected by the increased overall population, installing artificial nests, climate change, food abundance, habitat suitability, and human disturbances. Our results would contribute to the understanding of the population dynamics of Oriental Storks and provide a scientific basis for the development of conservation and management strategy specific to this species at Xingkai Lake.

Key words: Xingkai Lake, Oriental Stork, population dynamics, breeding population, migration.