2011-2012年青海省杂多县当曲湿地黑颈鹤及其他鸟类观察

Notes on 2011-2012 sightings of Black-necked Cranes(Grus nigricollis)and other birds in the Dam Chu Wetland,Zaduo County,Qinghai,China

广阔的当曲湿地(N32°54’,E94°08’)位于青海省杂多县境内,海拔4700 m。该湿地为一狭长区域,最大长度150 km、最大宽度60 km,由散布在蒿草和苔草草甸中的数千个池潭组成,池潭下为永久冻土层。湿地与当曲河上游交叉,该河流为黄河提供了最大的水源供给。由于地域偏僻,当曲湿地鲜有研究,虽然有关黑颈鹤(Grus nigricollis)的文献不断涌出,但并无关于该地黑颈鹤的记录。作者于2011年7月、2012年4月和2012年7月,对当曲湿地东部的局部进行了调查,3次分别记录到黑颈鹤4只、45只和14只。值得注意的是,2012年7月的调查中观察到3对繁殖黑颈鹤,并且分别带有出壳不久的2只幼鹤。尽管黑颈鹤在当曲湿地分布非常分散,该湿地仍是一个重要的黑颈鹤分布点和繁殖区。每年11月初至次年的5月初,当曲湿地都处于冰冻状态。随着区域温度的上升,每年的冰冻期将缩短,将可能导致黑颈鹤喜好的生境的扩增和黑颈鹤种群数量的增长。在该湿地还记录到5种哺乳动物和其他21种鸟类。基于当曲湿地黑颈鹤的种群数量,该湿地已具备认定为国际重要湿地的第二条标准。

The vast Dam Chu Wetland(N32°54’,E94°08’)lies at an elevation of 4,700 m in Qinghai’s Zaduo County.The wetland has maximum length and width of roughly 150 km and 60 km,respectively,and is comprised of thousands of permafrost-controlled ponds and pools set amidst Kobresia and Carex meadow ecosystems.The wetland is crossed by the upper Dam Chu River,the largest source of the Yangtze by volume.Due to its remote location,the Dam Chu Wetland is little studied,with an extensive literature review turning up no published crane records for the site.Three 2-3-day visits were made to the Dam Chu Wetland in July 2011,April 2012,and July 2012,during which three partial surveys of the eastern wetland were made resulting in Black-necked Crane counts of 4,45,and 14 individuals,respectively.Notably,in July 2012 three crane pairs were observed,each with a pair of recently hatched chicks.Although cranes in the Dam Chu Wetland are widely scattered,the wetland appears to be an important Black-necked Crane site and breeding ground.The wetland is frozen from about early November to early May each year.However,with regional warming,the annual frozen period is expected to shorten,possibly resulting in more favorable conditions for cranes and increased crane numbers.Five mammal and 21 other bird species were also sighted in the wetland.The Dam Chu Wetland currently qualifies for Ramsar designation under Criterion 2 based on its Black-necked Crane population.