Stomach content and faecal analysis of red-crowned crane (Grus japonensis) in Zhalong Wetland, Northeastern China

The discovery of eight dead red-crowned cranes in Zhalong Wetland, northeastern China, allowed us to examine their digestive tracts for identifiable prey in this study. Stomach content and fecal analyses were used to determine the foraging ecology of this crane species. The stomach content mass of the red-crowned crane carcasses varied according to body size and ranged from 10.62 g to 26.32 g. Grit particles prevailed in the stomach of the birds and accounted for approximately 87% of the mass of the stomach contents by weight (mainly gravel with particle sizes of 2–10 cm). Gizzard contents included plant and aquatic animals, which made up 63% and 37%, respectively, of the weight. Maize, seed, and fish were the most common residues in the gastric content; and zoobenthic debris, seeds, and reed organs were markedly present in the crane feces. The combined use of stomach content and fecal analyses is recommended for future studies on the food habits of this rare bird species.