Key Laboratory for Conserving Wildlife with Small Populations in Yunnan, Southwest Forestry University, Kunming, Yunnan, China.
Key Laboratory of Forest Disaster Warning and Control of Yunnan Province, Southwest Forestry University, Kunming, Yunnan, China.
Am J Primatol. 2023 Apr;85(4):e23467. doi: 10.1002/ajp.23467. Epub 2023 Jan 23.
Food availability and climate represent environmental factors that affect species' social behavior, ranging patterns, diet, and activity budget. From August 2012 to September 2013, we examined the effects of seasonal changes in food availability, temperature, and rainfall on the diet and behavioral ecology of Shortridge's langur (Trachypithecus shortridgei) an Endangered primate species inhabiting moist evergreen broadleaf forests in the Eastern Himalayas. Our field site represents the northernmost latitudinal distribution of this species. Data were collected using scan sampling at 10 min intervals, and analyzed based on generalized linear models. The results indicate that the langurs experienced two feeding peaks (9:00 and 17:00) and two traveling peaks (10:00 and 19:00) during each day. Periods of rest, mainly occurred between 10:00 and 13:00, and overnight. Feeding accounted for 38.5% of the daily activity budget, followed by resting (35%), traveling (24.5%), and socializing (2%). During periods when young leaves were most available, the langurs increased feeding time on young leaves (35% vs. 4%). During periods of maximum fruit availability, the langurs decreased total time spent feeding (36.6% vs. 40.4%), devoted more time to traveling (28.1% vs. 21%), and increased time spent consuming fruit (49.1% vs. 11.8%). During the winter, the langurs increased their consumption of mature leaves (44.5%) and reduced time spent traveling (20.2% vs. 25.4%). Overall, time spent resting was greatest in the spring (47.5%), time spent feeding was greatest during the summer (51.1%), and time spent in traveling was greatest in the autumn (33.2%). The frequency of social interactions remained relatively constant throughout the year. Foraging effort was greatest in the summer, when fruits dominated the diet. Like other species of temperate langurs, T. shortridgei devoted less time to resting, more time to feeding, and was characterized by a greater year-round foraging effort than tropical/subtropical langurs.
食物可获取性和气候是影响物种社会行为、活动范围模式、饮食和活动预算的环境因素。2012 年 8 月至 2013 年 9 月，我们研究了食物可获取性、温度和降雨量季节性变化对短尾猴（Trachypithecus shortridgei）饮食和行为生态学的影响。短尾猴是一种濒危灵长类物种，栖息在东喜马拉雅地区湿润的常绿阔叶林中。我们的研究地点代表了该物种最北的纬度分布区。我们使用 10 分钟间隔的扫描采样法收集数据，并基于广义线性模型进行分析。结果表明，短尾猴每天有两个进食高峰期（9:00 和 17:00）和两个活动高峰期（10:00 和 19:00）。休息时间主要发生在 10:00 至 13:00 之间，以及夜间。觅食占每日活动预算的 38.5%，其次是休息（35%）、活动（24.5%）和社交（2%）。在嫩叶最丰富的时期，短尾猴增加了对嫩叶的进食时间（35%对 4%）。在果实最丰富的时期，短尾猴减少了总进食时间（36.6%对 40.4%），更多地用于活动（28.1%对 21%），增加了食用果实的时间（49.1%对 11.8%）。在冬季，短尾猴增加了对成熟叶片的食用（44.5%），并减少了活动时间（20.2%对 25.4%）。总的来说，春季休息时间最长（47.5%），夏季进食时间最长（51.1%），秋季活动时间最长（33.2%）。社交互动的频率全年相对稳定。在夏季，当果实占主导地位时，觅食努力度最大。与其他温带长尾猴物种一样，短尾猴休息时间更少，进食时间更多，全年觅食努力度也高于热带/亚热带长尾猴物种。
