关键词: 滇金丝猴, 滞留时间, 残留比例, 种子大小

Abstract: Non-human primates are one of the three main seed dispersing groups, and it is crucial to evaluate the efficien cy of primate seed dispersal via the retention time and remaining percentage of seeds in their digestive tracts. To evalu ate the ability of black-and-white snub-nosed monkey (Rhinopithecus bieti), a rare and endangered primate, disperse seeds in temperate forest environments, we investigate digestive tract retention time and remaining percentage of seeds, and evaluate the relationship with the size of seeds. We fed an adult male R. bieti who just rescued in captivity with four species of fruits, namely Actinidia purpurea, Sorbus scalaris, Sorbus megalocarpa and Cotoneaster horizontalis, at the Tacheng Wildlife Rescue Station of Yunnan Baimaxueshan National Nature Reserve from October to November 2021. All feces excreted by the male R. bieti were collected and recorded, and the seeds remaining in the feces were sorted, and the time of seed excretion and the number of complete seeds were recorded. The mean retention time of the four fruit seeds through the digestive tract of R. bieti was (34.60 ± 8.34) h. The retention time of the fruit seeds through di gestive tract was influenced by the size of the seeds, with the smaller seeds the longer retention time (r_s=?0.519, n=12, P < 0.01). The mean percentage of fruit seeds remaining after passing through digestive tract was 17.7%(6.7%–61.7%), and the percentage of fruit seeds remaining after passing through their digestive tract was not affected by the size of seeds (r_s=0.17, n=12, P=0.957). The retention time of seeds in the digestive tract of R. bieti was less than that of the previous long-term caged individuals (34.6 vs. 47.0), and the retention time of seeds was influenced by seed size. Our results provide a reference for assessing the seed dispersal distance of R. bieti and experiment of germination rate in future. Therefore, as the R. bieti can spread plant seeds to enrich the soil seed bank and promote forest regenera tion, future conservation of this species can be called for in terms of the role of R. bieti in the ecosystem.

Key words: Rhinopithecus bieti, Digestive tract retention time, Remaining percentage, Seed size