Abstract:[Objective] To analyze the composition and metabolic characteristics of gut microbiota in Siberian crane (Grus leucogeranus) overwintering in the Poyang Lake. [Methods] The 16S rRNA gene high-throughput sequencing was employed to reveal the gut microbiota composition and PICRUSt to predict the function of Siberian crane overwintering in two artificial habitats (lotus field and paddy field) in the Poyang Lake. [Results] The alpha diversity indexes (Ace, Chao1, Shannon, and Simpson) showed that the gut microbiota diversity of Siberian crane in the paddy field were higher than those in the lotus field (P>0.05). The beta diversity based on Binary-Jaccard distance matrix revealed significant differences in the gut microbiota structure between the two artificial habitats (R2=0.312, P<0.05). The Siberian crane overwintering in different artificial habitats of the Poyang Lake showed varied gut microbiota composition. Terrisporobacter, Romboutsia, and Turicibacter were dominant genera in the gut of Siberian cranes in the lotus field, while Lactobacillus, Riemerella, and Catellicoccus in the paddy field. Line discriminant analysis effect size (LEfSe) analysis showed that the microorganisms like Lactobacillaceae, Lactobacillus, and Turicibacter with a strong ability to metabolize carbohydrates had significantly different relative abundance between the two artificial habitats. Functional prediction of PICRUSt showed that the intestinal microorganisms were mainly involved in metabolism, gene information processing, environmental information processing, and human diseases. At level 1, there were 5 types of metabolic pathways with significant differences (P<0.001). [Conclusion] Different species and number of birds and different food sources of the two artificial habitats resulted in significant differences in gut microbiota composition and characteristics of Siberian cranes overwintering in the Poyang Lake. PICRUSt functional prediction showed that there were significant differences in the abundance of functional genes of gut microbiota in the Siberian cranes overwintering in different artificial habitats, suggesting that Siberian cranes could adapt to the changes of food resources in artificial habitats by adjusting their gut microbiota. We preliminarily studied the composition and function of gut microbiota in the Siberian cranes overwintering in Poyang Lake. The findings underpin the relevant research and provide references for the conservation of overwintering Siberian cranes and the formulation of management measures.