| Chongming Dongtan is situated at the Estuary of Yangtze River, which is the main route that Asian migratory birds migrate by. It is an important district when migratory birds migrate by, on the other hand, there are many waterfowls living in this area in winter, so it is the most important part of the ecosystem which has international meaning. Many ornithologists have paid great attention to Chongming Dongtan for a long time.It is obvious that if we could study the birds of Chongming Dongtan widely and deeply, we can not only protect the plentiful resources of birds, but also let the world know Shanghai and improve the investment environment of Shanghai, and serve the sustainable development strategies of Shanghai.The researcher investigated the district of Chongming Dongtan from September, 2003 to April, 2004. We used the GPS, binocular and monocular telescope , and applied the line transect methods, spot observation and random sampling to study the waterfowls within and outside the sea wall in winter. From these data, we analyzed how they used different types of habitat and the situation of those waterfowls which were in severe danger, meanwhile, we talked about the protection circumstance about the birds of Chongming Dongtan. The results show as follows:1.This observation recorded 56 kinds of waterfowls totally, which belonged to 8 orders , 13 families. 14 species in Ciconiiformes, 6 species in Gruiformse, 17 species in Anseriformes, 16 species in Charadriiformes, 1 species in Gaviiformes, 1 species in Podicipedifromse, 1 species in Phalacrocoraciformes, 6 species in Lariformes. The largest number of them came from Anseriformes and Lariformes .They lived at five differernt types of habitat: algae saline transect, the zone of sea-bullrush, thezone of bullrush, reed transect and transect of crab(fish) ponds with reed behind the sea wall.2. The wetlands in Chongming Dongtan can be divided into two types of wetlands: natural wetland and artificial wetland. Natural wetland is the tidal wetland; artificial wetland include crab(fish) ponds and some rivers. The situation of the wintering waterfowls in Chongming Dongtan are influenced by the season characteristics, food amount, secrete quality and weather, etc. The crab(fish) ponds and reed belt are very important to the wintering waterfowls in Chongming Dongtan and have the highest value of species richness and abundance in five habitat types.The circumstance of saving or discharging water, water deepth and the percentage of plant's coverage have great influence on the distributing of waterfowls within the sea wall.3.We observed nine kinds of waterfowls which are in severe danger,including three kinds of national A-class protected rare birds:Hooded Crane(Gniy monachd), Black Stork(Cicoma nigra) ,Oriental Stork(Ciconia boyciana);six second kinds of national B-class rare birds:Black-faced Spoonbill(Platalea minor), Eurasian Spoonbill(Platalea leucorodia), Common Crane(Grus grus), Tundra Swan (Cygnus.c. jankowskii), Mandarin Duck (Aix galericulata) , White-naped Crane(Grw,s vipio). Black-faced Spoonbill is the new wintering bird record in Chongming Dongtan, and Black Stork(Ciconia nigra), Oriental Stork(Ciconia boyciana) and White-naped Crane(Grus vipio) reappeared after many years.These data show Chongming Dong is one of the most importmant wintering habitats for waterfowls. 4. From analyzing Shannon index in five different types of habitats, we discovered transect of crab(fish) ponds with reed behind the sea wall(artificial and half-aitificial wetlands) had the highest Shannon index, The results show that this type of habitat is very important to wintering waterfowls. The artificial and half-artificial wetlands are belong to trial regions within the sea wall, Now the situation of waterfowls in Chongming Dongtan is very dangerous .The reasons causing this situation mainly are the money and experts shortage in Chongming Dongtan Natural Reserve, overcatching, pollution, reclaiming tidalflats, hunting and ect...In order to resolvethese questions, some suggestion...
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