Influences of submerged plant collapse on diet composition, breadth, and overlap among four crane species at Poyang Lake, China

作者：Jinjin Hou, Lei Li, Yafang Wang, Wenjuan Wang, Huiying Zhan, Nianhua Dai, Ping Lu · 发表于：Frontiers in Zoology · 年份：2021 · DOI：10.1186/s12983-021-00411-2 · 被引用次数：47 · 研究领域：Environmental DNA in Biodiversity Studies、Aquatic Ecosystems and Phytoplankton Dynamics、Freshwater macroinvertebrate diversity and ecology

BACKGROUND: Interannual variation in resource abundance has become more unpredictable, and food shortages have increasingly occurred in the recent decades. However, compared to seasonal fluctuations in resource abundance, the influences of interannual variation in resource abundance on the dietary niches of consumers remain poorly understood. Poyang Lake, China, is a very important wintering ground for the globally endangered Siberian Crane (Leucogeranus leucogeranus), White-naped Crane (Grus vipio), and Hooded Crane (G. monacha), as well as the non-endangered Eurasian Crane (G. grus). Tubers of Vallisneria spp., the dominant submerged macrophytes at Poyang Lake, is an important food for cranes. Nevertheless, submerged macrophytes have experienced serious degradation recently. In this study, we used metabarcoding technology to explore the consequences of Vallisneria tuber collapse on the diet compositions, breadths, and overlaps of the four crane species based on fecal samples collected in winter 2017 (a year with tuber collapse) and winter 2018 (a year with high tuber abundance). RESULTS: Compared to previous studies, our study elucidates crane diets in an unprecedented level of detail. Vallisneria tubers was confirmed as an important food source of cranes. Surprisingly, the grassland plant Polygonum criopolitanum was also found to be an important food source in the feces of cranes. Agricultural fields were important foraging sites for Siberian Cranes, White-naped Cranes, an...