Diet of the Assamese macaque Macaca assamensis in lime- stone habitats of Nonggang, China

To enhance our understanding of dietary adaptations in macaques we studied the diet of the Assamese macaque Macaca assamensis in limestone seasonal rain forests at Nonggang Nature Reserve, China from September 2005 to August 2006. Our results show that although macaques fed on many plant species, 85.2% of the diet came from only 12 species, of which a bamboo species, Indocalamus calcicolus contributed to 62% of the diet. Young leaves were staple food items （74.1% of the diet） for Assamese macaques at Nonggang, and constituted the bulk of monthly diets almost year-round, ranging from 44.9% （July） to 92.9% （May）. Young parts of Indocalamus calcicolus unexpanded leaves contributed to a large proportion of the young leaf diet in most months. Fruit accounted for only 17.4% of the diet, with a peak of consumption in July. We suggest that this highly fo- livorous diet may be related to the long lean season of fruit availability in limestone habitats as well as the utilization of cliffs of low fruit availability

Variations in diet composition of sympatric Trachypithecus francoisi and Macaca assamensis in the limestone habitats of Nonggang, China

Comparative studies of sympatric species are essential for understanding behavioral and ecological adaptation as well as the mechanisms that can reduce resource competition to allow coexistence. Francois＇ langurs （Trachypithecus francoisi） and Assamese macaques （Macaca assamensis） are sympatric primate species found in the limestone seasonal rainforests of Nonggang Nature Reserve, southwestern Guangxi, China. To explore their different adaptation strategies, we collected data on diet using scan sampling at 15-min intervals. Our results revealed that Francois＇ langurs showed a more flexible diet composition than Assamese macaques Francois＇ langurs increased dietary diversity and mature leaf consumption in response to seasonal scarcity of preferred young leaves and fruits, whereas Assamese macaques relied heavily on young bamboo leaves （Indocalamus calcicolus） in most months These variations reflect the differences in digestive physiology, morphology, and the temporal and spatial distribution of food resources.