Composition And Spatial Distribution Pattern Of Anatidae In Yunnan Wetland During Winter

Yunnan wetlands is located in the confluence of two major global migratory channels---central Asia-India and east Asia-Australia migration channel,which is an important wintering area and stopover sites for water birds.The current composition and spatial distribution of Anatidae in Yunnan wetlands were only sporadic records,lacked of knowledge system.In order to explore the status and means of the Anatidae of Yunnan province in the migratory bird migration routes around the world.,this paper studies the composition and time-space distribution of Anatidae in Yunnan province.Based on predecessors' materials,the latest data of Anatidae and their habitats were investigated and collected by the fixed-point counting method and sample line method in 26 lake or reservoir wetlands of Yunnan province.With the help of Similarity analysis,SPSS19.0 for Person correlation analysis and “Biodixcel for Excel2007”,we conducted the result as follow.(1)Toward 33659 times for 22 species were recorded,and are all winter visitor.The largest number is Anser indicus(29.76% of the total number),Tadorna ferruginea(14.60%)and Netta rufina(8.50%).The highest frequency is Anas strepera,Tadorna ferruginea and Aythya nyroca.Anser fabalis and Anser albifrons are rare winter visitor in Yunnan province.A total of 36 species were found in Yunnan province by collecting and sort out the previous research materials,accounted for 70.59% of the national,less than 2 kinds of Sichuan province,more than 4 kinds of Guangxi province,and more than 6 kinds of Guizhou province.(2)The largest number of community is Napahai lake,Luguhu lake and Lashihai lake on average.Both species and quantity,northwestern Yunnan are more,central Yunnan and eastern Yunnan are less.Anatidae had a higher similarity between central Yunnan and northeastern Yunnan,as well as between southeastern Yunnan and northeastern Yunnan.(3)Anser fabalis,Anser albifrons,Anas querquedula,Tadorna tadorna,Aix galericulata,Anas falcate and Bucephala clangula are relatively rare,only a few individuals were recorded in individual wetland.Anser anser is mainly distributed in Lashihai lake(accounting for 72.71% of the total average number).Anser indicus is mainly distributed in Napahai lake(82.42%).Tadorna ferruginea is mainly distributed in Caohai lake(29.11%),Napahai lake(24.12%)and Lashihai lake(11.43%).Anas Penelope is mainly distributed in Napahai lake(23.40%),Lashihai lake(20.75%)and Dianchi lake(18.51%).Anas strepera is mainly distributed in Lashihai lake(36.16%)and Napahai lake(32.23%).Anas crecca is mainly distributed in Qingshuihai lake(20.78%),Caohai lake(19.65%)and Sanjiaohai lake(13.74%).Anas platyrhynchos is mainly distributed in Napahai lake(47.65%)and Cibihu lake(14.12%).Anas poecilorhyncha is mainly distributed in Caohai lake(43.85%)and Jianhu lake(26.64%).Anas acuta is mainly distributed in Datunhai lake(26.95%),Qingshuihai lake(23.22%)and Napahai lake(21.82%).Anas clypeata is mainly distributed in Datunhai lake(33.56%),Nianhu lake(20.13%)and Dianchi lake(15.77%).Netta rufina is mainly distributed in the Luguhu lake(99.34%).Aythya ferina is mainly distributed in Napahai lake(29.58%)and Luguhu lake(26.79%).Aythya nyroca is mainly distributed in Cibihu lake(47.77%),Luguhu lake(14.31%)and Caohai lake(13.75%).Aythya fuligula is mainly distributed in Qingshuihai lake(57.95%).Mergus merganser is mainly distributed in Napahai lake(42.91%),Nianhu lake(14.92%)and Tiaodunhe reservoir(11.27%).(4)The species and number of Anatidae has increased significantly in Napahai lake since 1984.The species of Anatidae has been decreasing in Erhai lake since 1984.The species of Anatidae has been decreasing or even disappearing in Xingyunhu lake since 1983.The species of Anatidae has first increased and then decreased in Lashihai lake since 1984.The species and number of Anatidae has decreased significantly in Yilonghu lake since 2007.(5)The wintering habitat of Anser anser,Anser indicus and Bucephala clangula is contracting towards the north in Yunnan province.