Research On The Spatiotemperal Dynamics And Dominant Species Breeding Ecology Of Birds In Tanghai Wetlands, Hebei Province

Based on the field survey, we compared the Hebei Tanghai wetlands seasonal avian community characteristics and evaluated the quality of regional environment in this paper. Furthermore, we studied reproductive behavior and nest relationship of ardeidae birds which play a special role in local ecosystem, and proposed correlative measures to some problems faced by the regional birds. The major researchful results are following:1. The structure of avian community and migration dynamic of main groups. According to investigation, there are 301 species of birds in all belonging to 138 genus, 58 families and 18 orders, among which there are 185 species of non-passeriformes sharing 61.46% of the total birds. There are 195 species of transient migrants in this area accounting for 64.78% of the total number, 60 species of summer migrants, 30 speices of resident and 16 species of winter migrants. Among them, 6 species (1.99%) viewed as the national first-grade protected birds were recorded, including Golden Eagle, Imterial Eagle, Pallas's Fish Eagle, Red-crowned Crane, Siberian Crane and Great Bustard, and 41(13.62%) of the recorded species were the national second-grade protected wildlife, including Dalmatian Pelican, Chinese Egret, Oriental Stork, Eurasian Spoonbill, Black-faced Spoonbill, Greater White-fronted Goose, Whooper Swan, Mandarin Duck, Northern Goshawk, Upland Buzzard, Peregrine Falcon, Common Crane, White-naped Crane, Little Curlew, Long-eared Owl and so on. In view of distinct characters, the Palaearitic realm are dominant (214), the next are the widespread species(75) and the Oriental realm (12), which is the transition from North Type to North-east Type. Some species are dense in the region such as Tree Sparrow, Black-headed Gull, Barn Swallow, White-cheeked Starling, Red Knot, Black-tailed Godwit, Dunlin, Marsh Sandpiper, etc, and Marsh Sandpiper, Asian Dowitcher, Great Knot, Red Knot, Sharp-tailed Sandpiper, Curlew Sandpiper, Grey Plover and 8 species of Charadriidae and Scoipacidae even preponderate over the international important significance indicator. The migration peaks mainly occurred in spring or fall for the four species of waterfowls. In fall, the migration time was comparatively compact, focusing in the period from the last ten days of September to the middle ten days of October, however, there were two migration peaks in spring: Anatidae in March and Charadriidae and Scoipacidae, the gulls, Ardeidae after April, which is relatedwith the regional climate and bird food habit.2. Comparison on avian community among natural and acquired six habitats. Tideland, iodine weed brushwood as well as reed and swamp habitat represents the earlier, transitional and topmost period of the natural evolvement of costal wetlands, respectively, while salt fields and shrimp ponds, paddy fields and forest shrubs belong to the acquired habitats. The sequence of density is tideland, forest shrub and paddy field habitat. The sequence of species richness is reed and swamp, forest shrub, tideland, costal shrimp, iodine weed brushwood and paddy field habit. The sequence of indices on species and family and genera diversity is reed and swamp (4.078 and 0.747, respectively), self-restraint shelter forest (3.908 and 0.617) and paddy field habitat (2.436 and 0.381). To the species similarity degree, it is the highest (0.512) between tideland and salt field and shrimp pond habitat, the next are 0.486 between reed and swamp and salt field and shrimp habitat, and 0.024 between tideland and forest shrub habitat.3. Breeding ecology of ardeidae birds. The four heron species namely Black-crowned night herons, Egrets, Chinese pond-herons and Great egrets stayed for a long time in this area. There were altogether two nest areas I and II area, and the maximum occurred from April to September almost up to 5800 individuals, with immigrating events later in II area than I area about half a month. During breeding stage, Black-crowned Night Herons dominant in member number immigrated firstly occupying the upper nests in the nuclear area, while Chinese Pond Herons emerged lastly with less population most solely nidifying in edges and merely few taking the lower nests of the core. Egrets monopolized the middle nests but comparatively late, and Great Egrets least in member size also occupied the upper nests in the central area. As a whole, it was the widest to Egrets in the vertical niche, to Black-crowned Night Herons in level niche and to Chinese Pond Herons in holistic space niche. Nest distribution pattern was the most similar between Chinese Pond Herons and Black-crowned Night Herons, while the niche overlap of Chinese Pond Herons and Egrets was the highest. Owning to maximum members and the largest body respectively, Black-crowned night herons and Great egrets controlled Egrets and Chinese pond-herons in conflict. In addition, we discussed that the primary cause which resulted in plentiful aigrets in the wetlands might be rich food and fitting forest-zones. Nest sites found only inbilateral-poplar zones above 22 m was the distinguishing feature of this wetlands.4. Existent problems and relevant advices. The contradiction between bird hunting, tidal flat development, oil exploitation, port construction as well as local human production and bird foraging is increasingly severe. Thus it is necessary for the local government to enforce management, spread propaganda and establish reasonable effective measures for protecting birds.