Post-Graduate Programme in Wildlife Biology and Conservation, National Centre for Biological Sciences, Bangalore, India.
Am J Primatol. 2011 Dec;73(12):1250-60. doi: 10.1002/ajp.20997. Epub 2011 Sep 6.
Tropical rainforests show seasonal fluctuations in the abundance of fruits resulting in periods of resource scarcity for frugivores. We examined the response of an obligate frugivore, the lion-tailed macaque (LTM) (Macaca silenus), to a period of fruit scarcity in a rainforest in the Western Ghats, India. We estimated the abundance and distribution of fruit resources from food tree densities obtained from 348 point centered quadrats, and fruit availability from phenological monitoring of 195 trees of 15 reported major food species. Macronutrient content was estimated for fruits of 15 major food species. We estimated time spent feeding on different food items from 1,853 individual scans spanning 120 hr of observation of one habituated study group. There was a distinct period of fruit scarcity during the drier months of February to mid-March (Period 1) compared with late March and April (Period 2), separated by summer showers. Fruits available in Period 1 had lower soluble carbohydrate and lipid content and overall caloric value compared with Period 2. During the lean period, the LTM fed more on fruits of Drypetes wightii, which had the highest carbohydrate content, than on nectar of Palaquium ellipticum or Ficus spp., which had low carbohydrate content. During this period, the resource availability in a location significantly influenced the occurrence of feeding there. In Period 2, the group fed most on the seeds of Cullenia exarillata, the most abundant tree in the home-range and with the highest content of soluble carbohydrates. During this period, the abundance of food trees in fruit in a location did not seem to influence the occurrence of feeding. Low abundance, stochastic fruiting and, low quality might make Ficus spp. a poor fallback option for the LTM.
热带雨林的果实丰度存在季节性波动，导致食果动物在一段时间内面临资源匮乏的问题。我们研究了一种专食果实的动物——狮尾猕猴（Macaca silenus）在印度西高止山脉的热带雨林中，对果实匮乏期的反应。我们通过对 348 个以点为中心的样方中食物树密度的测定，以及对 15 种主要食物树种的物候监测，来估算果实资源的丰度和分布。我们还对 15 种主要食物树种的果实进行了宏量营养素含量的估计。通过对一个已适应的研究群体进行 120 小时观察，获取 1853 个个体扫描，从而估计其对不同食物的进食时间。与 3 月下旬和 4 月（第 2 期）相比，2 月至 3 月中旬（第 1 期）的旱季明显出现了果实匮乏期，其间有夏雨期分隔。与第 2 期相比，第 1 期可食用的果实具有较低的可溶性碳水化合物和脂质含量，以及总体热量值。在这段时间里，狮尾猕猴更多地食用了旱树（Drypetes wightii）的果实，因为它含有最高的碳水化合物，而不是低碳水化合物含量的 Palauquium ellipticum 或榕属（Ficus spp.）的花蜜。在这段时间里，一个地点的资源可利用性显著影响了在此地点的觅食行为的发生。在第 2 期，该群体主要以 Cullenia exarillata 的种子为食，而 Cullenia exarillata 是其活动范围内最丰富的树种，且含有最高的可溶性碳水化合物。在这段时间里，一个地点的食物树的果实丰度似乎并不影响觅食行为的发生。果实数量少、随机结果和低质量可能使榕属（Ficus spp.）成为狮尾猕猴的一个较差的备用食物来源。
