Nutrient composition and food availability determine food choices and foraging strategies of animals. Altitude affects species distribution and food availability, whereas primate food needs increase with body size. However, the mechanism of food selection in large primates at low altitudes requires further investigation. As the largest species in the genus Macaca, the Tibetan macaque (Macaca thibetana) has sophisticated foraging strategies. In this study, we researched a group of 29 wild Tibetan macaques (Tianhu Mountain Group) that live in a low-altitude area around Mt. Huangshan, Anhui Province, China. We used instantaneous and scan sampling for observing the foraging behavior of these macaques from September 2020 to August 2021. We recorded the dietary composition and food availability, compared the nutrient content of staple food and non-food items, and analyzed the role of key nutrients in food selection. We found that Tibetan macaques forage on 111 plants belonging to 93 genera and 55 families. The food types included 52.5% fruits, 17.0% mature leaves, 6.3% young leaves, 1.9% stems, 4.5% flowers, 14.4% bamboo shoots, 1.3% tender shoots, and 2.1% other. Tibetan macaques forage for a maximum total of 76 plant species during spring. However, dietary diversity was highest during summer (H’=3.052). Monthly fruit consumption was positively correlated with food availability. Staple foods are lower in fiber and tannins than non-foods. In addition, there was a positive correlation between the time spent foraging for specific foods and sugar content of the food. The results showed that the plant species and food types fed by Tibetan macaques were diverse, and their foraging strategies varied seasonally. Our findings confirm the effect of nutrients on food choice in Tibetan macaques, highlighting the importance of sugar in their food choices and suggesting that the foraging behavior of Tibetan macaques is highly flexible and adaptive.
The main strategy for animal diversity conservation is to increase the territory size but little consideration is given to habitat characteristics requirement, which lead to a decrease in effectiveness for protected areas. Marginal of protected areas are considered to have higher species richness due to the edge effect. Strategy in these sites are still adopts to increase territory size or pay no attention to needs of specific habitat characteristics that is an important topic for the planner and manager. In this study, camera traps was used to estimate composition, diversity and habitat characteristics of mammals in a non-protected area near Huangshan Mountains in Anhui Province, China. We ran 49 liner models with the relative abundance index and 13 habitat characteristic factors of 11 mammals. To answer the question of habitat characteristics or territory size: which is more important to composition and diversity of mammals in non-protect area? We hypothesized that: (1) Non-protected areas have more mammal species than protected areas with the edge effect. (2) Non-protected areas have more species associated with habitat characteristics. We predicted that the habitat characteristics should be firstly considered, territory size secondly in non-protected areas, would provide a last refuge for mammals. Cameras were operated from June 2017 to October 2019, for a total of 29 months, 2,212 independent photos, 9,485 trap-days, recorded 18 species of mammals more than any other protected areas confirmed first hypothesis 1. The model analysis results showed that, habitat characteristics of mammals were different and showed a significant correlation, supported hypothesis 2. In addition, most species are related to vegetation characteristics except to primates (Macaca. thibetana) and rodent (Leopoldamys edwardsi) confirmed our prediction. We suggested conservation policies in non-protected areas: Habitat characteristics should be concerned at first and then increasing protected areas to provide the last refuge for species conservation.