This study is the first to have surveyed the population of black-necked cranes (Grus nigricollis) at the Longbao National Nature Reserve, Qinghai, China, throughout most of the 7.5 month annual crane residence period, with 17 crane counts having been made on the reserve's main wetland between 6 April and 16 November 2011. In 2011, the first cranes are believed to have arrived at Longbao at the end of March, and the last are believed to have departed between 7 and 11 November. The peak adult black-necked crane count was 216 on 25 April, while the low count was 81 on 23 October, which increased to 153 during migration staging on 6 November. This represents a 9-fold increase in the peak annual adult crane count since the earliest known count from 1984. Twenty-nine nests were observed in the survey area in May and June, and on 12 September 2011, 21 of 29 nesting pairs had surviving chicks, with 9 crane pairs having a pair of surviving chicks, while 12 crane pairs had a single surviving chick. Threats to cranes at Longbao include untied dogs, which harass breeding cranes, eat eggs, and kill chicks; recently erected power lines along the wetland, which may prove hard for cranes to see and avoid; and disturbance of nesting cranes from humans and their livestock. Other threats include climate change, which is drying up shallow wetlands in the Longbao region and elsewhere on the Tibetan Plateau, and severe degradation of hillslope pastures, which is forcing local herders to keep their yaks on the main wetland pastures for longer periods each year and will inevitably cause increased disturbance to cranes and further degradation of the wetland. The Longbao Wetland presently qualifies for Ramsar designation based on its black-necked crane population under Ramsar Criteria 2 and 6.
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