Abstract: Reeves'muntjac (Muntiacus reevesi) is distributed in the south of Yangtze River in East Asia, and is the Muntiacus species with the largest distribution range in China. In this study, we combined the data from camera-trapping surveys conducted from 2011 to 2020 in six nature reserves in the Minshan Mountains, Sichuan Province. With an extensive survey effort of 75 320 camera-days at 726 valid camera stations, we obtained 20 236 images and videos from 1 903 independent detections of Reeves'muntjac at 133 camera stations. Our results showed that the sex ratio of adults in this wild population of Reeves'muntjac was ♀:♂=1. 13:1. The majority of observed Reeves'muntjac were solitary individuals, accounting for 91. 97% of total independent detections, followed by male-female pairs, accounting for 6. 15% of the total detection times. Other group types included doe-fawn group, buck-fawn group, family group, two female group, two male group and one male with two female group, all together accounted for 2. 88% of the total independent detections. The Reeves'muntjac in Minshan Mountains had a bimodal daily activity rhythm, with one activity peak at 06:00-09:00 around dawn and another at 17:00-19:00 around dusk, showing a typical crepuscular pattern. Its daily activity pattern showed substantial seasonal variations, with the greatest difference between that in winter and summer. On the basis of extensive datasets from field camera-trapping surveys, our study determined the sex ratio, social structure and daily activity pattern of Reeves'muntjac in Minshan Mountains, which will provide reliable basic information to support and guide future studies on the wild populations of this small Cervidae species.

Key words: Ungulates, Sex ration, Daily activity pattern, Camera-trapping, Wildlife monitoring, Minshan Mountains

摘要： 小麂（Muntiacus reevesi）主要分布在东亚长江以南的地区，是我国分布范围最广的麂属物种。本研究基于四川省岷山山脉6个自然保护区2011—2020年的红外相机调查数据，共布设有效调查位点726个，完成75 320个相机日的有效调查工作量；在其中133个相机位点上拍摄到小麂照片和视频20 236份，独立探测1 903次。分析结果显示，岷山地区野生小麂种群中成年个体雌雄性比为1.13∶1。小麂的集群类型多样，以单只活动为主，占总探测次数的91.97%；其次为雌雄对，占总探测次数的6.15%；其余较为少见的集群模式有母幼群、父幼群、家庭群、双雌、双雄与单雄双雌，合计占总探测次数的2.88%。岷山地区小麂的日活动节律呈双峰型，分别在日出前后的06：00—09：00和日落前后的17：00—19：00各存在1个活动高峰，为典型的晨昏活动型；小麂不同季节的日活动节律之间存在差异，以冬季与夏季间的差异尤为明显。本研究基于大数据量的野外实地调查记录，探明了岷山地区小麂种群的性比、社会结构和日活动节律，为该小型鹿科物种野外种群的后续研究提供了可靠的基础信息。

关键词: 有蹄类, 性别比例, 日活动节律, 红外相机技术, 野生动物监测, 岷山山脉