Migratory Waterbirds Survey In Dunhuang, Gansu Province

Waterbird surveys were conducted at 19 different sites from 2006-2008 in Dunhuang,Gansu province.The species component and migrate seasonal dynamic of waterbird community were studied in Dunhuan.The relation between waterbirds abundance and habitat features were analysed with Canonical Correspondence Analysis.The factors threatening the existence of the waterbirds were found and some conservation strategies were suggested.After investigation and data analysis,it mainly contains 7 results.(1) 55 species of waterbirds were recorded during the fieldwork in Dunhaung from 2006-2008. These birds belong to 6 orders,12 families,including 5 Gansu new record birds,1 species of national first-grade protected wildlife,3 species of national second-grade protected wildlife.Anatidae are the dominant family that contains 21 species of waterbirds,account for 27.63%of the total.Charadriidae and Scolopacidae were the second dominant families,both contains 7 species of waterbirds,account for 9.21%of the total respectively.Among the total,46 species are passage migrant,account for 83.64%,11 species are summer visitor,account for 20%,4 species are resident,account for 7.27%.(2) 11,491 individuals were recorded during the survey.In spring,the total abundance of waterbirds is 2117.09.Dabbling ducks and Geese,Waders were the dominant guilds,account for 39% and 31%of the total abundance respectively.Yangguan reservoir and Yumenguan wetland complex were the sites which have more abundance waterbirds in spring;In autumn,the total abundance of waterbirds are 655.83.Dabbling ducks and Geese,Diving ducks and Coots were the dominant guilds, account for 53%and 22%of the total abundance respectively.Yangguan and Danghe reservoirs were the sites which have more abundance waterbirds in autumn.(3) The waterbirds community diversities were analyzed between 19 study sites by using the Shannon-Wiener index.Yangguan reservoir,Yangshuihaizi,Nandahu,Danghe reservoir and Dunziwan were the sites which have more waterbird diversity in spring.Danghe reservoir,Yangguan reservoir, Yangshuihaizi,Yanchiwan,Nandahu were the sites which have more waterbird diversity in autumn.(4) There were 45 species of waterbirds recorded in reservoirs and 42 species recorded in natural wetlands.34 species of waterbirds were both recorded in the reservoirs and natural wetlands.In spring, there is more waterbirds in natural wetlands than reservoirs.In autumn,there is more waterbirds in reservoirs due to the decrease of water in natural wetlands.(5) According the CCA analysis,the maximum water depth in wetlands were the most important habitat feature explaining the pattrns of distribution of waterbirds,followed by proportion of open water and freshwater marsh areas in the wetlands. (6) The irrationality in water supply in riverbasin and wetland reserves planning layout,lack wetland management skill are the most important factors threatening the existence of waterbirds in Dunhuang.In order to protect the waterbirds and wetlands in Dunhuang,more ecological water in natural wetlands should be strive for and the planning layout of wetland reserves must be improve and the management of wetland should be strengthened in the near future.