生物多样性 ›› 2021, Vol. 29 ›› Issue (6): 770-779.  DOI: 10.17520/biods.2020388

所属专题: 青藏高原生物多样性与生态安全

• 研究报告: 动物多样性 • 上一篇    下一篇

基于视频监控系统的欧亚水獭活动节律初报及红外相机监测效果评估

韩雪松1,2, 董正一1,3, 赵格1, 赵翔1, 史湘莹1,4, 吕植1,5, 李宏奇6,*()   

  1. 1.山水自然保护中心, 北京 100871
    2.Department of Geography, University of Cambridge, Cambridge CB2 1BN
    3.Department of Biology, Lund University, Lund 223 62
    4.北京大学环境科学与工程学院, 北京 100871
    5.北京大学生命科学学院自然保护与社会发展研究中心, 北京 100871
    6.青海省环境工程技术评估中心, 西宁 810007
  • 收稿日期:2020-10-08 接受日期:2020-12-27 出版日期:2021-06-20 发布日期:2021-02-18
  • 通讯作者: 李宏奇
  • 作者简介:* E-mail: 13327676380@163.com

Using surveillance cameras to analyze the activity pattern of the Eurasian otters (Lutra lutra) and the efficiency of camera trap monitoring

Xuesong Han1,2, Zhengyi Dong1,3, Ge Zhao1, Xiang Zhao1, Xiangying Shi1,4, Zhi Lü1,5, Hongqi Li6,*()   

  1. 1 Shan Shui Conservation Center, Beijing 100871, China
    2 Department of Geography, University of Cambridge, Cambridge CB2 1BN, UK
    3 Department of Biology, Lund University, Lund 223 62, Sweden
    4 College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
    5 Center for Nature and Society, School of Life Sciences, Peking University, Beijing 100871, China
    6 Environmental Engineering Assessment Center of Qinghai Province, Xining 810007, China
  • Received:2020-10-08 Accepted:2020-12-27 Online:2021-06-20 Published:2021-02-18
  • Contact: Hongqi Li

摘要:

欧亚水獭(Lutra lutra)是淡水生态系统保护的旗舰物种, 目前三江源或为其在中国仅存的连片栖息地之一。然而, 该区域欧亚水獭基础生态学信息尚属空白, 已开展的工作也多依赖于红外相机而可靠性有待评估。本文基于2018-2020年间在青海玉树通过视频监控系统和红外相机收集到的数据, 在分析区内水獭活动节律的同时, 对红外相机监测的有效性和准确性进行了评估。结果表明, 在玉树, 欧亚水獭在每日17时至次日9时活动频率较高, 每年12月至次年6月间拍摄频率较高; 繁殖期或随每年10月个体交配而开始, 至次年6月幼崽独立而终止。红外相机约可捕获69.18%的水獭出现事件, 且拍摄率随事件持续时间的延长而提高; 通过红外相机可以准确地描述出水獭活动节律, 仅有约半数红外相机影像可以准确还原事件主题(56.28%)和多只个体参与的事件中的个体数量(49.35%)。因此, 在使用红外相机对欧亚水獭进行行为学研究时应对这一情况进行充分考虑。

关键词: 欧亚水獭, 三江源, 视频监控系统, 红外相机, 活动节律, 繁殖行为

Abstract

Aim: The Eurasian otter (Lutra lutra) is a flagship species for global freshwater ecosystems. As one of the most widely distributed Palearctic mammals, the otter used to inhabit most provinces in China. However, after decades of relentless hunting and habitat degradation, the Sanjiangyuan Region is now one of last strongholds for this species in China. Currently, there still remains an enormous knowledge gap in basic information about this species. Available field information has mostly been acquired through camera trapping, and the reliability of this method is still being questioned considering the revealed underperformance in the monitoring for otters.

Method:Research was conducted in Yushu City, Qinghai Province. We deployed surveillance cameras and camera traps in five monitoring sites with high otter occurrences from Oct. 2018 to May 2020. Using data collected from the surveillance cameras, we analyzed daily and annual activity patterns for the Eurasian otters in the region. To better understand the breeding period for otters, we analyzed the temporal distribution of all breeding related events. Furthermore, using surveillance cameras as reference, we evaluated the efficiency (detection rate, captured duration) and accuracy (behavior/topic, individual number) of camera traps for otter monitoring.

Results:Surveillance cameras recorded 1,033 independent events of the Eurasian otters, and 597 of them were captured by camera traps (Oct.-May). The otters were highly active from 17:00 to 09:00 (+1 day) and there was a higher capture frequency from December to June (+1 year). Most breeding related events were captured from October to April (+1 year). Camera traps detected 69.18% of otter occurrence events, which was positively correlated with an increase in event duration (0-49 s). The temporal distribution of events captured by camera traps showed a significant linear relationship with surveillance camera records, but the durations were significantly shorter. Finally, only 56.28% of the events captured by camera traps provided enough information to discern the otter's behavior; for events with more than one individual, only 49.35% of the camera trap records accurately captured otter's number.

Conclusions:The daily and annual activity patterns of the Eurasian otters in Yushu City were proven in accordance with the precious research conducted in other inland riverine ecosystems. By analyzing breeding related events, we found that the breeding season of the Eurasian otters in Yushu begins with mating behavior starting in October and ending with the dispersal of cubs by June. Although 30.82% of the events were missed by camera traps, they still accurately documented the daily and annual activity patterns of the Eurasian otters. However, because of the amount of missed information, camera traps are not the most reliable method for further quantitative behavioral studies on Eurasian otters.

Key words: Eurasian otter (Lutra lutra), Sanjiangyuan, surveillance camera, camera trap, activity pattern, breeding behavior