Ma Chi, Fan Peng-Fei, Zhang Zhong-Yuan, Li Jia-Hong, Shi Xiao-Chun, Xiao Wen
Institute of Eastern-Himalaya Biodiversity Research, Dali University, Dali, P.R. China.
School of Life Sciences, Sun Yat-Sen University, Guangzhou, P.R. China.
Am J Primatol. 2017 Oct;79(10). doi: 10.1002/ajp.22695. Epub 2017 Sep 6.
In habitats such as temperate evergreen forests, fruit, and seed productivity is reported to exhibit marked changes in seasonal availability, such that fruit is most available in summer and seeds are most available in autumn. Primates living in these habitats, therefore, are expected to adjust their diets in response to the spatial and temporal variation in these food resources. We studied the diet and feeding behavior of a group of 42 Phayre's langurs (Trachypithecus phayrei) living in a northern (24°48'N) montane habitat (1,700-2,350 m) in Mt. Gaoligong, Yunnan, China from August 2012 to July 2013. The langurs were found to forage on 50 plant species, of which 28 species each accounted for more than 1% of their annual feeding time. Castanopsis echidnocarpa, the most abundant species in their habitat, accounted for 17.5% of the total forest trees, and contributed to the largest proportion of the annual langur diet. The primary component of the langur diet was composed of fruits (22.2%), seeds (18.7%), and buds and young leaves (41.5%). Mature leaves accounted for only 4.1% of their diet. Based on DBH and the percent of the crown containing edible food items, we found that the langurs changed their monthly diet according to the availability of fruits and seeds (Spearman rank correlation: r = 0.609, p = 0.035), and buds and young leaves (Spearman rank correlation: r = 0.837, p = 0.001). The seeds of C. echidnocarpa accounted for 12.5% of langur feeding time. A single tree produced a large seed and fruit crop, which likely reduced opportunities for within-group feeding competition. We argue that the resource productivity of this northern montane enables Phayre's langurs to live in stable groups that are 3.6 times larger than reported for Phayre's langurs living in other habitats.
在诸如温带常绿森林等栖息地，据报道水果和种子的产量在季节性可获得性方面呈现出显著变化，即水果在夏季最为丰富，种子在秋季最为丰富。因此，生活在这些栖息地的灵长类动物预计会根据这些食物资源的时空变化来调整它们的饮食。我们研究了一群42只菲氏叶猴（Trachypithecus phayrei）的饮食和觅食行为，这些叶猴生活在中国云南高黎贡山北部（北纬24°48′）的山地栖息地（海拔1700 - 2350米），研究时间为2012年8月至2013年7月。发现这些叶猴以50种植物为食，其中28种植物各自占它们全年觅食时间的1%以上。它们栖息地中数量最多的物种——刺栲（Castanopsis echidnocarpa），占森林树木总数的17.5%，在叶猴全年饮食中所占比例最大。叶猴饮食的主要成分包括水果（22.2%）、种子（18.7%）以及芽和嫩叶（41.5%）。成熟叶片仅占它们饮食的4.1%。基于胸径以及树冠中包含可食用食物部分的比例，我们发现叶猴会根据水果和种子的可获得性（斯皮尔曼等级相关：r = 0.609，p = 0.035）以及芽和嫩叶的可获得性（斯皮尔曼等级相关：r = 0.837，p = 0.001）来改变它们每月的饮食。刺栲的种子占叶猴觅食时间的12.5%。一棵树上产出大量的种子和果实，这可能减少了群体内觅食竞争的机会。我们认为，这个北部山地的资源生产力使菲氏叶猴能够生活在稳定的群体中，其群体规模比生活在其他栖息地的菲氏叶猴群体规模大3.6倍。
