A Study On Potential Available Food For Wintering Black-Headed Gulls In Lakeside Of Dianchi

The shortage of enough natural food in wetlands of Dianchi Lake was believed as one of reasons why people were fond of feeding the wintering Black-headed Gulls with amount of man made food. There was however no scientific research to such parlance. Twenty-six sampling sites the lakeside of Dianchi Lake and downtown of Kunming city were chosen to estimate quantity of available food for the wintering Black-headed Gulls, during the period from November2011to October2012. Based on methodology including data processing, statistics, one-way ANOVA, and cluster analysis, results were obtained as follows.(1) There was enough available food for the wintering Black-headed Gulls stored in wetlands of Dianchi Lake. The available food of wintering black-headed gulls weighs about0.93×108g was stored from0to100cm water depth in the Dianchi Lake. It means that the lake can provide25.27times food for35000black-headed gulls’food consumption (3.68×106g/d). This illustrated that there is enough food to supply the wintering black-headed gulls in the Dianchi Lake.(2) The amount of available food for the wintering Black-headed Gulls in wetlands was significantly low during their wintering period. There were significant differences in the food of fish, shrimps, and insects between months, but there was no significant difference in the food of snails monthly. Many aquatic organisms were breeding in the April to the July, so the food will be increased which means it can provide enough food for the wintering black-headed gulls.(3) No obvious spatial differentiation was fond about the distribution of available food in the studied area. Overall the storage capacity of available food was higher in the locations with less anthropogenic interference. And it was lower in the more anthropogenic interference locations which was Cuihu、Lianhuachi、Zhuantang.(4) The amount of available food is rich in shallow water with dense aquatic plants.It was concluded that the appropriate reduction of man made food for the wintering Black-headed Gull is necessary to maintain the wildness of black-headed gulls. We can attract the black-headed gulls to the locations just like Geziwo、Sanhe village、 Dongdahe、Haikou wetland、Huiwan with less human interference and abundance food if we encounter the prevalence of avian influenza years. So we can avoid spread of the people-gull diseases. We can retain black-headed gulls better if the Dianchi Lake was strengthened recovery and reconstruction, and also it was conducive to increase the amount of food.