贵州草海越冬水鸟数量及其近20年来的变化

Numbers of wintering waterbirds and their changes over the past 20 years at Caohai,Guizhou Province

草海位于云贵高原东缘的贵州省西北部,是中国西南部最为重要的水鸟越冬地和停歇地。为了确定草海越冬的水鸟种类、数量和草海的分布,分析近20年以来的草海水鸟的数量变化以及变化原因,于2012年1月11-12日对草海国家级自然保护区越冬水鸟进行了调查。该次调查共计数到水鸟26种,76872只。这26种水鸟中,超过1000只个体的有8种,分别为绿翅鸭(Anas crecca)、黑颈鹤(Grus nigricollis)、斑嘴鸭(Anas poecilorhyncha)、斑头雁(Anser indicus)、凤头潜鸭(Aythya fuligula)、赤麻鸭(Tadorna ferruginea)、赤颈鸭(Anas penelope)和骨顶鸡(Fulica atra)。数量接近或超过10000只的有3种,依次是骨顶鸡、赤颈鸭和赤麻鸭。在过去20年,草海冬季水鸟的总数量为50000~80000只。黑颈鹤数量呈稳定上升趋势,而灰鹤数量呈下降趋势。潜鸭类水鸟数量总数不到2600只,与1996年调查的10000多只相差很大。这可能与草海近10年来水质恶化,导致潜鸭类水鸟植物性食物减少有关。建议把草海水鸟调查工作纳入到保护区的监测保护工作日程中,每年冬季开展至少一次调查;使用统一和系统的水鸟监测方法,使得不同年份的监测结果具有可比性;密切关注那些种群急剧上升(如黑水鸡)和下降的物种(如潜鸭类);开展草海土地利用变化的监测工作,以便探讨土地利用与鸟类之间的相互关系;在过去20年中,黑颈鹤种群上升,而灰鹤种群下降,因此两者之间的相互关系应该加以研究;草海正在面临很多的诸如污染、外来物种入侵、旅游业等十分迫切的环境问题,这些环境因子对水鸟种群的影响也亟需加以研究和解决。

Caohai,lying on the eastern Yunnan and Guizhou Plateau,is the most important wintering and stopover area for waterbirds in the southwestern China.To document species,their populations,and changes of waterbirds wintering at Caohai,a survey was conducted on 11-12 January 2012.Twenty-six species of waterbirds,with a total of 76,872 individuals were recorded.Of the 26 species of waterbirds,8 species had a population of more than 1,000,including Common Teal(Anas crecca),Black-necked Crane(Grus nigricollis),Spot-billed Duck(Anas poecilorhyncha),Bar-headed Goose(Anser indicus),Tufted Duck(Aythya fuligula),Ruddy Shelduck(Tadorna ferruginea),Eurasian Wigeon(Anas penelope),and Coot(Fulica atra).Coot,Eurasian Wigeon,and Ruddy Shelducks each had population of near 10,000 or more.Over the past 20 years,the total counts of waterbirds have been between 50,000-80,000.Numbers of Black-necked Cranes have been increasing steadily,while Eurasian Cranes(Grus grus)have been declining.The number of diving ducks is far less than the number of 10,000 diving ducks in 1996,likely due to the decline in water quality at Caohai over the past decades.We recommended the following measures be taken into account in waterbird monitoring and protection:more systematic waterbird count;special attention paid to species or groups with dramatic increase or decrease;land use and change to be monitored;and urgent measures to be taken on pollution,invasive species,urban expansion,and tourists.