Foraging Success and Habitat Selection of the Eurasian Spoonbill (Platalea leucorodia) at Poyang Lake, China

Abstract

Poyang Lake is China's largest freshwater lake in summer and provides important habitat for an internationally significant assemblage of waterbirds in winter. Human-caused alterations to this system threaten to compromise the long-term viability of these bird populations due to the role of water in driving habitat suitability. Little is known, however, about the patch-scale habitat selection strategies of waterbirds within Poyang. Consequently, there is potential for spatial incongruence between protected area boundaries and key habitats given the system's high variability. This study used scan and focal sampling techniques to investigate patch selection by a wintering population of the Eurasian Spoonbill (Platalea leucorodia) within the Sha Hu sub-lake basin of Poyang Lake. Eurasian Spoonbills averaged higher foraging success rates in areas with water depth of 28.1-36.6 cm compared to other areas and preferred to forage in this depth class, as indicated by usage disproportionate to availability (Manly's standardized selection index = 0.817). Defining the patch-scale habitat selection of this indicator species both quantifies the impact of hydrological changes on resource availability and spatially predicts suitable areas for wintering birdlife within a dynamic environment.