秦皇岛黄胸鹀和蓝歌鸲的种群动态及迁徙时序——基于1999—2019年的环志数据

Population Dynamic and Migration Timing of Yellow-breasted Bunting Emberiza aureola and Siberian Blue Robin Larvivora cyane in Qinhuangdao, China: Based on Banding Data during 1999-2019

鸟类环志是种群监测和迁徙研究的重要手段。基于秦皇岛鸟类环志站1999~2019年的环志数据,对黄胸鹀(Emberiza aureola)和蓝歌鸲(Larvivora cyane)两种鸟类在21年间的种群动态和迁徙时序进行了分析。结果表明,迁徙途经秦皇岛的黄胸鹀种群数量以4或5年为周期呈规律性的波动下降,年均降幅达17.3%,21年间种群数量累计下降了97.7%。近年来我国加强了对黄胸鹀及其栖息地的保护管理,并于2021年初将其列为国家I级重点保护动物,有望促进其种群的逐步恢复。蓝歌鸲种群数量的年均降幅为4.2%,但下降过程主要集中在1999至2003年间,其后种群指数趋于稳定。黄胸鹀春季网捕高峰短暂而集中,持续约15d;秋季网捕高峰则较为分散,持续约47d。这表明黄胸鹀春季迁徙进程明显较为集中和快速,可能是出于繁殖需求采取了时间最短的迁徙策略。蓝歌鸲成年雄鸟、成年雌鸟和亚成鸟春季的网捕高峰在日期上有明显的差异,间隔4或5 d先后出现,表明蓝歌鸲不同年龄和性别的个体在春季进行差别迁徙,有利于减小停歇地的种内竞争,并确保雄鸟提前到达繁殖地占领优质的繁殖领域。

The Yellow-breasted Bunting Emberiza aureola and the Siberian Blue Robin Larvivora cyane are typical migrants along the East Asian-Australasian flyway. While the global population of the Yellow-breasted Bunting has experienced dramatic decrease over the past two decades and the population of the Siberian Blue Robin also shows a declining trend, however, their population status in China still remains unclear. Bird banding provides important data to monitor bird population dynamic and bird migration. The Qinhuangdao Bird Banding Station is situated at a forest farm at Bohai Bay, and locates in north middle section of the East Asian-Australasian Flyway, with a variety of migratory passerines. Based on the banding data from the Qinhuangdao Bird Banding Station during 1999 to 2019, we analyzed the population dynamic and migration timing of Yellow-breasted Bunting and Siberian Blue Robin. The results indicated that the population of Yellow-breasted Bunting fluctuated in a 4﹣5 year-cycle, and decreased by 97.7% in the past 21 years at an annual rate of ﹣17.3%(Fig. 1). China government has enhanced the conservation and management of Yellow-breasted Bunting and its habitats in recent years, and listed it as a First Class National Protected Animal in early 2021, which would contribute to its population recovery gradually. The population of Siberian Blue Robin decreased by 4.2% annually. The decreasing mainly occurred during 1999 to 2003 and thereafter the population kept stable(Fig. 1). The daily capture peak of Yellow-breasted Bunting kept for about 15 days in spring, much shorter than the duration of 47 days in autumn(Fig. 2). This indicated that Yellow-breasted Bunting migrated much faster in spring than that in autumn, probably due to a time-minimization strategy for breeding. The capture peak of adult male, adult female and juvenile of Siberian Blue Robin occurred in sequence, with an interval of 4﹣5 days(Fig. 3), indicating that this species took a strategy of differential migration so as to reduce intraspecific competition at stopover sites and resting grounds, and adult males arriving earlier in breeding grounds to occupy optimal territory. To better understand the extent of population decline of the population of Yellow-breasted Bunting and other vulnerable passerine species in East AsianAustralasian flyway, and efficiently save these birds, we suggest a jointly standardized field survey such as bird banding in the flyway level(Table 1), and taking measures to resume habitats and control illegal hunting.