Spatiotemporal dynamics of ecological variation of waterbird habitats in Dongtan area of Chongming Island

Abstract

Based on Landsat TM images, we explored the pattern of variation of suitable waterbird habitats from 1990 to 2008 in the Dongtan area of Chongming Island at the Changjiang (Yangtze) River mouth. By applying our highly accurate indicator model (R=0.999, P SMZ>TSH (total suitable habitat)>BSA (bare mud flat and shallow water area). The abandonment of tracts of aquaculture ponds in Dongtan in mid-2006 brought about an intensive population fluctuation, caused by rapidly changing habitat with the population expanding to adjacent areas. At present, Anatidae and Ardeidae are threatened in the Dongtan area with declining populations because of their very “picky” habitat requirements (i.e., high reliance on AP). The Charadriidae experienced enormous population declines in the late 1990s, however, they have since recovered to normal levels as habitat change has stabilized. Our findings suggest that the current challenges for habitat management are the protection and stabilization of AP and SMZ habitats.