[论文解读] Prey selection of Amur tigers in relation to the spatiotemporal overlap with prey across the Sino-Russian border

Hailong Dou, Haitao Yang+4 more|arXiv (Cornell University)|Oct 26, 2018

Wildlife Ecology and Conservation参考文献 58被引用 8

一句话总结

本研究利用粪便分析与相机陷阱技术，调查了中国东北珲春自然保护区阿穆尔虎的猎物选择情况，评估其与猎物在时空上的重叠程度。结果表明，老虎偏好野猪和赤鹿，因其具有较高的时间重叠度与较大的体型，其饮食中94.9%来自野生猎物，凸显了活动同步性与空间共现性在塑造捕食策略中的作用。

ABSTRACT

The endangered Amur tiger is confined primarily to a narrow area along the border with Russia in Northeast China. Little is known about the foraging strategies of this small subpopulation in Hunchun Nature Reserve on the Chinese side of the border; at this location, the prey base and land use patterns are distinctly different from those in the larger population of the Sikhote-Alin Mountains of Russia. Using dietary analysis of scats and camera-trapping data from Hunchun Nature Reserve, we assessed spatiotemporal overlap of tigers and their prey and identified prey selection patterns to enhance understanding of the ecological requirements of tigers in Northeast China. Results indicated that wild prey constituted 94.9% of the total biomass consumed by tigers; domestic livestock represented 5.1% of the diet. Two species, wild boar and sika deer , collectively represented 83% of the biomass consumed by tigers. Despite lower spatial overlap of tigers and wild boar compared to tigers and sika deer, tigers preferentially preyed on boar, likely facilitated by high temporal overlap in activity patterns. Tigers exhibit significant spatial overlap with sika deer, likely favoring a high level of tiger predation on this large-sized ungulate. However, tigers did not preferred roe deer (Capreolus pygargus) and showed a low spatial overlap with roe deer. Overall, our results suggest that tiger prey selection is determined by prey body size and also overlap in tiger and prey use of time or space. Also, we suggest that strategies designed to minimize livestock forays into forested lands may be important for decreasing the livestock depredation by tigers. This study offers a framework to simultaneously integrate food habit analysis with the distribution of predators and prey through time and space to provide a comprehensive understanding of foraging strategies of large carnivores.

研究动机与目标

• 了解中国东北中-俄边境小型孤立亚种群阿穆尔虎的捕食策略。
• 评估老虎与猎物之间时空重叠如何影响猎物选择模式。
• 利用粪便分析量化饮食组成并识别老虎饮食中的主要猎物物种。
• 评估猎物体型与活动同步性在塑造捕食偏好中的作用。
• 通过识别导致家畜捕食的因素并提出缓解措施，为保护策略提供依据。

提出的方法

• 通过粪便分析确定不同猎物物种对老虎饮食的组成及生物量贡献。
• 收集相机陷阱数据，以估算老虎及其主要猎物物种的空间与时间活动模式。
• 利用活动时间分配数据与空间共现指标，量化老虎与猎物之间的时空重叠。
• 通过基于生物量的饮食分析，比较实际猎物消耗与可利用性，评估猎物选择。
• 应用统计模型，评估空间重叠、时间重叠及猎物体型对捕食偏好的影响。
• 整合时间与空间上的生态数据，构建分析大型食肉动物捕食策略的综合框架。

实验结果

研究问题

• RQ1 阿穆尔虎与猎物在珲春自然保护区的时空重叠如何影响猎物选择？
• RQ2 哪些猎物物种对中国人侵亚种群老虎的饮食生物量贡献最大？
• RQ3 猎物体型与活动模式同步性在多大程度上影响老虎的捕食偏好？
• RQ4 为何老虎偏好野猪，尽管其与野猪的空间重叠度低于赤鹿？
• RQ5 导致家畜捕食的因素有哪些？在人与野生动物共存策略中如何减少此类事件？

主要发现

• 野生猎物占老虎总摄食生物量的94.9%，家畜占5.1%。
• 野猪与赤鹿合计占老虎总猎物生物量的83%。
• 老虎虽与野猪的空间重叠度较低，但仍表现出偏好，可能由于活动模式的时间重叠度高。
• 老虎与赤鹿存在显著的空间重叠，这可能促进了对这种大型偶蹄类动物的高捕食率。
• 尽管与狍子有中等空间重叠，老虎并不偏好该物种，原因在于时间重叠度低且体型较小。
• 本研究证实，在破碎化栖息地中，猎物体型与时空共现性均为决定老虎猎物选择的关键因素。