评估荒漠猫的日活动节律:基于红外相机与卫星颈圈数据的对比

Determining the daily activity pattern of Chinese mountain cat(Felis bieti):A comparative study based on camera-trapping and satellite collar tracking data

对于活动隐秘、难以直接观察的野生猫科动物,红外相机与卫星追踪颈圈是目前研究其日活动节律的两种主要采样工具。日活动节律基于对动物活跃状态(即活跃或不活跃)的判断,由于获取数据的机制不同,两种方法所获得的动物日活动节律模式之间可能存在差异,但缺乏基于野外实地调查的系统对比评估和分析。荒漠猫(Felisbieti)分布于青藏高原东部,是唯一的中国特有猫科动物,被列为国家I级重点保护野生动物。本研究以荒漠猫为例,使用红外相机和卫星追踪颈圈两种工具,于2020年6月至2021年12月对青海祁连山地区的荒漠猫进行调查,分别基于放置在荒漠猫洞口(相机位点2个,独立有效探测173次)、兽径(相机位点23个,独立有效探测423次)两种红外相机布设方式和卫星追踪颈圈(追踪个体10只,总有效定位点62,942个)所得的数据,评估了该物种的日活动节律,并对不同途径所得的活动节律模式间的差异进行了对比。结果显示,荒漠猫全天都有活动,在黄昏17:00–19:00时段存在一个活动高峰。全部红外相机探测数据与颈圈活动量数据获得的活动曲线重叠系数最高,为0.89。与卫星追踪颈圈方法相比,红外相机数据反映出16:00–21:00的活动水平更高;这一时间段较高的活动主要来自洞口位点的红外相机探测数据。荒漠猫行为谱的对比分析结果显示,不同方法所判断的动物“活跃”状态所对应的行为类型不同:安装在洞口处的红外相机记录以繁殖、育幼相关的社会行为为主;安装在兽径处的红外相机记录以移动、觅食等行为为主;而卫星追踪颈圈只能相对粗略地区分荒漠猫的移动和静止。本研究的结果表明,不同方法所获得的野生猫科动物的“活动节律”之间存在差异;在不同方法记录到的数据中,二元化的“活跃”或“不活跃”分类背后所反映的动物行为类别和含义是不同的。在对比不同方法获得的活动节律时需要谨慎,应在对动物的行为模式和规律深入全面了解的基础上,对数据做出恰当、准确的解读。

Aims:For elusive and difficult to observe wild cats,camera trap and satellite tracking collar are widely used sampling methods to determine daily activity patterns.While satellite tracking collars can continuously monitor a limited number of captured individuals,camera traps have the potential to monitor all population members in a given area.The detection probability of camera traps for wild cat activity patterns is likely influenced by the selected spatial placement of the cameras.The activity patterns are constructed based on the binary classification of target animals’active status(i.e.,active or inactive).Although the different methods of monitoring wild cats may lead to different activity patterns,few empirical studies have examined the difference between the patterns.The Chinese mountain cat(Felis bieti),a small felid endemic to China,is distributed in the eastern and northern edge of the Qinghai-Tibet Plateau at low density.The Chinese mountain cat was uplisted to Class-I National Key Protected Wildlife of China in 2021,is listed as Vulnerable(VU)by the IUCN Red List,and is considered Critically Endangered(CR)in China’s Red List.However,the existing surveys and data are insufficient to carry out conservation of Chinese mountain cat.Therefore,urgent field investigations about the ecological activities of the Chinese mountain cat are needed.Methods:From June 2020 to December 2021,we investigated activity patterns of Chinese mountain cats in Qilian Mountains of Qinghai Province using camera traps and satellite-tracking collars.We compared daily activity patterns derived from camera traps placed at den sites(2 sites,173 independent detections)and animal trails(23 sites,423independent detections),to satellite-tracking collars fitted on Chinese mountain cats(10 individuals,62,942 fixed locations).Results:Results show Chinese mountain cats were active all day long,with peak activity from 17:00 to 19:00.A daily activity curve produced by camera traps showed a high level of overlap with results produced by the activity sensor implanted in the collars;the coefficient of overlap is 0.89.However,the camera traps showed significantly higher levels of activity from 16:00 to 21:00.Detection of activity from 16:00 to 21:00 was primarily concentrated at a small range of den sites.Concurrently,activity records of the collars were relatively lower.Based on the ethogram of Chinese mountain cat,activity patterns recorded from the camera traps placed at den sites predominantly represents social behaviors related to reproduction and nursing while activity records from the trail camera traps generally represent movement and foraging.The satellite-tracking collar was limited to distinguishing just the movement and still of an individually tracked animal.Conclusions:Our results indicate considerable differences between the activity patterns of wild cats obtained via camera-trapping and a satellite collar tracking.The binary classification of“active”or“inactive”used to construct activity patterns reflect different behaviors in data derived from different methods.Caution should be taken for researchers when comparing the activity patterns derived from different studies.Proper and accurate interpretation of data should be made on the basis of in-depth and comprehensive understanding of the target animal’s behaviors.