Within-group female-female feeding competition and inter-matriline feeding competition in Taiwanese macaques (Macaca cyclopis) at Fushan Experimental Forest, Taiwan (China)

The results of my studies confirmed that the female Taiwanese macaques at Fushan Experimental Forest have a frugivorous diet and exhibits dominance hierarchies. The female macaques experienced within-group contest feeding competition, in accordance with predictions of the socioecological model (van Schaik, 1989). The females exhibited a higher proportion of aggression over higher-quality foods such as animal matter and reproductive parts of plants than lower-quality foods such as other plant parts. Higher agonism rates occurred in small food patches than in large food patches. The high-ranking females tended to monopolize fruits in small food patches.; Rank-related effects on feeding patterns and reproductive success of the females caused by within-feeding competition were detected. The high-ranking females spent significantly less time searching for food than did the low-ranking females. Time spent feeding on food resources of different qualities by the females was not found to be correlated to their social ranks. However, the high-ranking females exhibited higher feeding rates on an important fruit resource and highly competed-for leaves than did the low-ranking females. The high-ranking females had higher reproductive success than the low-ranking females as well. The rank-related differences in feeding patterns and reproductive success in the female macaques confirmed that food contributes to shaping social structure and female social relationships in the Taiwanese macaque society.; Inter-matriline feeding competition occurred over fruits of Machilus japonica. Higher agonism occurred than expected between matrilines, while lower agonism occurred within matrilines. The high-ranking matrilines had greater access to the better feeding sites than did the low-ranking matrilines in the tree crown of Machilus japonica. When kin was present in proximity, the monkeys gained relatively better access to the better feeding sites. This result provided evidence on the direct benefits of association with kin in the context of feeding.