Habitat Selection Of Hooded Crane(Grus Monacha)Wintering At The Lakes Of Yangtze River Floodplain In Anhui Province

Hooded Crane is a vulnerable wading bird which is sensitive to the change of wetlands. The size of the population wintering in China was about1200. The lake wetlands in the middle and lower reaches of Yangtze River are important wintering habitats for Hooded Crane, of which over-exploitation already became threat to wintering cranes recently. To investigate its ecological adaptation to wetland degradation, a research on habitat condition and habitat selection of Hooded Crane was needed. Our research could also provide a theoretical basis for wetland habitat restoration and wintering population protection.We used route survey method to investigate the population number and distribution of cranes. The Vanderploeg and Scavia electivity index (Ei) was used to measure the degree of preference of each habitat. We also used sampling method to get the ecological factor of foraging habitat. DCA was used to analyze the habitat selection.The biggest number of wintering population in Caizi Lake was113individuals, and193individuals in Shengjin Lake. Both decline dramatically compared with documental wintering populations. More cranes distributed in artificial wetland, like paddy fields and polders. In Shengjin Lake, most cranes distributed in grass land near by Yangetou Village pound and Shegan Village and paddy fields of Bailian and Xinsheng. In Shengjin Lake, most cranes stayed in paddy fields near Meihua Village and grass land near Bajiao. The shrink of two wintering populations and less forage in mud flat shows the cranes had to faced on the threats of fishery.The types and abundance of food resource in each habitat were different. The results of One-Way ANOVA analysis showed that the density of food in grass land and paddy field were very significantly higher than the other habitats. The results of Kruskal-Wallis Hanalysis showed that the number of food and depth of food in two preferred habitat were significant higher than the other three habitats (0.01<P<0.05).The results of correlation analysis between foraging degree and3characteristics of food showed significant positive correlation between biomass of food and foraging degree, and it’s strongest in all (r=0.650,P=0.000). Biomass of food made a difference to foraging microhabitat selection.DCA analysis of habitat factors showed that the factors with the highest correlation coefficient are water depth (r=0.831), vegetation coverage (r=-0.729), the distance from water (r=-0.632). Variety of habitat types at different times in the two-axis there was a clear separation of the distribution. The population in Shengjin Lake showed deferent distribution of habitat in grass land and shallow water, and the changes also took place in grass land, paddy field and mudflats in Caizi Lake.