Department of Environmental Science, Policy, and Management, University of California Berkeley, Berkeley, CA, USA.
National Center for Ecological Analysis and Synthesis, Santa Barbara, CA, USA.
J Anim Ecol. 2022 Jan;91(1):46-60. doi: 10.1111/1365-2656.13621. Epub 2021 Nov 4.
Spatiotemporal variation in predation risk arises from interactions between landscape heterogeneity, predator densities and predator hunting mode, generating landscapes of fear for prey species that can have important effects on prey behaviour and ecosystem dynamics. As widespread apex predators, humans present a significant source of risk for hunted animal populations. Spatiotemporal patterns of risk from hunters can overlap or contrast with patterns of risk from other predators. Human infrastructure can also reshape spatial patterns of risk by facilitating or impeding hunter or predator movement, or deterring predators that are themselves wary of humans. We examined how anthropogenic and natural landscape features interact with hunting modes of rifle hunters and mountain lions Puma concolor to generate spatiotemporal patterns of risk for their primary prey. We explored the implications of human-modified landscapes of fear for Columbian black-tailed deer Odocoileus hemionus columbianus in Mendocino County, California. We used historical harvest records, hunter GPS trackers and camera trap records of mountain lions to model patterns of risk for deer. We then used camera traps to examine deer spatial and temporal activity patterns in response to this variation in risk. Hunters and mountain lions exhibited distinct, contrasting patterns of spatiotemporal activity. Risk from rifle hunters, who rely on long lines of sight, was highest in open grasslands and near roads and was confined to the daytime. Risk from mountain lions, an ambush predator, was highest in dense shrubland habitat, farther from developed areas, and during the night and crepuscular periods. Areas of human settlement provided a refuge from both hunters and mountain lions. We found no evidence that deer avoided risk in space at the scale of our observations, but deer adjusted their temporal activity patterns to reduce the risk of encounters with humans and mountain lions in areas of higher risk. Our study demonstrates that interactions between human infrastructure, habitat cover and predator hunting mode can result in distinct spatial patterns of predation risk from hunters and other predators that may lead to trade-offs for prey species. However, distinct diel activity patterns of predators may create vacant hunting domains that reduce costly trade-offs for prey. Our study highlights the importance of temporal partitioning as a mechanism of predation risk avoidance.
捕食风险的时空变化源于景观异质性、捕食者密度和捕食者狩猎模式之间的相互作用，为猎物物种产生了恐惧景观，这可能对猎物行为和生态系统动态产生重要影响。作为广泛存在的顶级捕食者，人类对被捕猎动物种群构成了重大威胁。猎人的风险的时空模式可能与其他捕食者的风险模式重叠或形成对比。人类基础设施也可以通过促进或阻碍猎人或捕食者的移动，或阻止对人类警惕的捕食者，从而重塑风险的空间模式。我们研究了人为和自然景观特征如何与步枪猎人的狩猎模式以及美洲狮 Puma concolor 相互作用，为它们的主要猎物生成风险的时空模式。我们探讨了加利福尼亚门多西诺县人为恐惧景观对哥伦比亚黑尾鹿 Odocoileus hemionus columbianus 的影响。我们使用历史上的狩猎记录、猎人 GPS 追踪器和美洲狮的相机陷阱记录来模拟鹿的风险模式。然后，我们使用相机陷阱来观察鹿对这种风险变化的时空活动模式。步枪猎人依靠长视线，他们的活动具有明显的、相反的时空模式。而依赖伏击的美洲狮的风险最高的地方是茂密的灌木栖息地，远离开发区域，在夜间和黄昏时期。人类居住的地区是猎人及美洲狮的避难所。我们没有发现鹿在我们观察的范围内在空间上避免风险的证据，但鹿会调整它们的时间活动模式，以减少在高风险地区与人类和美洲狮相遇的风险。我们的研究表明，人类基础设施、栖息地覆盖和捕食者狩猎模式之间的相互作用可能导致来自猎人及其他捕食者的不同的空间捕食风险模式，这可能会导致猎物物种之间的权衡取舍。然而，捕食者明显的昼夜活动模式可能会产生空缺的狩猎区域，从而减少猎物的高成本权衡取舍。我们的研究强调了时间分割作为避免捕食风险的一种机制的重要性。
