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The study of habitat selection and diet has a long history in ecology. This is often used to assess the functional roles of wetland in biodiversity conservation. Shifting habitat and diet may be one of the survival strategies during extremely adverse conditions. Therefore, sudden changes in habitat selection may indicate the deterioration of the habitat quality, and management interventions are necessary. Siberian crane (Grus leucogeranus) became critically endangered due to loss of habitat, and is currently a global conservation focus. Every winter, more than 95% of the species' global population congregates at Poyang Lake, and feeds on tubers of Vallisneria spiralis in shallow water and mudflat habitat. In this study, we reported the first sighting of large numbers of Siberian cranes foraging at wet meadows, where they fed on a different plant, Potentilla limprichtii due to extreme scarcity of their preferred tuber. To understand how well the cranes adapted to such unusual habitat, field surveys to assess the distribution of cranes across different habitats, and food availability in each habitat were carried out in the winter of 2011. Field observations on crane behaviors at different habitats were also conducted. Results show that cranes displayed significantly different behavior patterns when using the wet meadow, compared to the crane's optimal habitat - shallow water and mudflat. Both juveniles and adults spent significantly less time foraging, and more time alerting in meadows than in shallow waters and mudflats. These results indicated that the meadow might be a suboptimal wintering ground for Siberian crane, which helped the cranes survive from extreme unfavorable conditions. To some degree, this finding alleviates the general concern over the fluctuating of its food resources which was caused by hydrological disturbances. However, more studies are needed to assess the consequences of such diet and habitat shift for crane survival. [ABSTRACT FROM AUTHOR]

Wuliangsuhai wetland is one of the representative wetlands in arid-semiarid region. It is also a key breeding site as well as a stepping site for both East Asia-Australasia Flyway and Central Asia Flyway. From 2009 to 2012, surveys on migratory water birds and their habitat were carried out by using transects census and spot count methods. The surveys recorded more than 100 000 water birds, and 98 species were identified, which belong to 6 orders and 14 families. Among the 98 species, 55 are summer residents (breeding here) and 39 are travelers (only stay here shortly), which account for 56.12% and 39.80% of the total recorded bird species respectively. Further analysis on their migration pattern shows that spring migration is mainly from early March to mid May, which is shorter than autumn migration season (from early August to mid November). Most of the summer residents breed from early April to late May. High concentration of key protected species were observed from early April to early May and from early September to early November. The bird community structure is relatively stable in summer, but much more dynamic during the migration seasons (spring and autumn). Based on the study, recommendation to nominate Wuliangsuhai wetlands as Ramsar site, and flyway network site were put forward. Habitat management that address to the environmental determinants on bird distribution was also discussed. [ABSTRACT FROM AUTHOR]