The Use Of Coastal Artificial Wetlands By Birds In Migratory Seasons

As the staging areas for migratory birds following the Australian-Asia flyaway and connections between the Asian continent and Indochina, wetlands in Shankou Mangrove Nature Reserve are very important for bird migration. Shankou Mangrove Nature Reserve is located in North Bay Economic Zone, how to deal with the contradiction between economic development and wetland birds and their habitats will be of far-reaching impact.We did researches on the use of coastal artificial wetlands (i.e. farmlands, saline and aquacultural ponds), comparison the bird use of natural wetlands and artificial wetlands, the composition of artificial wetland birds, the effect of artificial wetland habitat variables on birds. The main results were as follows:1. Farmlands provided a good habitat and food resources for a large number of herons and migratory landbirds.61 bird species, belonging 21 families 7 orders were recorded in farmland habitats. There were significant linear relationships between habitat variables and bird richness and abundance by Spearman correlation analysis. The Vegetation and water status were the first selected habitat factors of waterbirds.2. Saline and aquacultural ponds were good alternatives to natural wetlands for herons and shorebirds.56 bird species, belonging 19 families 8 orders were recorded in saline and aquacultural ponds. There were also significant linear relationships between habitat variables and bird richness and abundance by Spearman correlation analysis. Herons showed no selectivity in habitat variables of saline and aquacultural ponds. Water depth, tide and vegetation status were the key factors in the use of saline and aquacultural ponds by shorebirds.3. Coastal artificial wetlands were good alternatives to natural wetlands for waterbirds at high tide.39 waterbird species, belonging 8 families 6 orders were recorded in natural wetlands.50 waterbird species, belonging 9 families 6 orders were recorded in artificial wetlands. The species richness was higher in artificial wetlands than in natural wetlands. The species abundance was higher in artificial wetlands than in natural wetlands in spring, and was lower in artificial wetlands than in natural wetlands in autumn. There was a significant difference in percentage of foraging shorebirds between natural wetlands and artificial wetlands (t=3.986, p<0.001). Natural wetlands were important foraging habitat for shorebirds, and herons and shorebirds used artificial wetlands as rest area.On the basis of the above conclusions, some management recommendations to improve the quality of habitats for birds could be given:to improve the conservations of the remained natural wetlands; to increase the heterogeneity of farmlands; to maintain water depth and vegetation diversity in saline and aquacultural ponds in migratory seasons.