Abstract: Tibetan snowcock (Tetraogallus tibetanus) is a secondclass national protected animal in China, inhabiting in the alpine bare rocks and meadows of QinghaiTibetan Plateau and the adjacent areas. Little information on the diet of Tibetan snowcocks is available. We collected all plant species that may be eaten by the birds and the fresh feces of Tibetan snowcocks in the foraging habitat on the mountain in Luowa Village, Jianzha County, Qinghai Province from May to August in 2016. The diet was determined by microscopic fecal analysis. The proportion of each identified plant species was calculated. The results showed that all plant organs can be eaten by the birds. Leaves are preferred, followed by stems, flowers, seeds, and roots were rarely eaten. The proportion of plant organs exhibited seasonal variation. The proportion of leaves gradually decreased, that of stems changed little, that of flowers increased obviously in July, and that of fruits (seeds) increased sharply in August (28%). A total of  72 plant species from 24 families were found in snowcocks’ habitat, with Pteridophyta, Bryophyta, and Lichenes being also eaten. Most of the plants (49 species categorized into 19 families) as well as Bryophyta and Lichenes were the food source. Gramineae and Compositae were the main food source, accounting for more than 42% of its diet. Poa pratensis (22.35%) was the main food species of snowcocks, and 20 species including Taraxacum mongolicum were the common food. From May to August, the variation of the proportion of plant species eaten by the birds was obvious. The proportion of Poa pratensis was stabilized at about 20% from May to July, and rose to 30.20% in August, while the proportion of Taraxacum mongolicum generally increased from May to August. The number of plant species eaten by Tibetan snowcocks was relatively stable (35-36 species) from May toAugust and slightly higher (41 species) in July. Food composition of Tibetan snowcocks in different months showed higher similarity (>73%). Shannon diversity index and Pielou evenness index were similar from May to August, but the food niche breadth in August was significantly lower than that in other months. In conclusion, the dietary of Tibetan snowcocks is wide and with a distinct seasonal variation. Our results can provide a basis for the design of artificial feed for a rescue and ex-situ protection of Tibetan snowcocks.

Key words: Tibetan snowcock (Tetraogallus tibetanus), microscopic fecal analysis, diet composition, seasonal variation.