DISSERTATION RESEARCH: Can avoidance behavior and landscape complexity explain patterns of predator coexistence in mammalian carnivores?

这个项目探索了非洲大型食肉动物的种群动态，询问斑点鬣狗、豹子和猎豹是如何与狮子生活在一起的，因为狮子经常骚扰和杀死这些较小的食肉动物。研究人员将把对狮子的调查数据与相机陷阱的数据结合起来，以确定鬣狗、豹子和猎豹如何在与狮子相关的景观中分布，以及栖息地使用的差异如何使这些物种在有狮子和没有狮子的情况下共存。了解捕食者如何共存对于了解大型生态系统如何运作很重要。最近的研究强调了顶级捕食者对生态系统的深远影响；破坏捕食者的数量会以意想不到的方式破坏自然系统的稳定。预测不稳定发生的方式和原因的能力是防止具有多种捕食者的生态系统生态崩溃的必要的第一步。这个项目将通过一个公民科学平台（www.SnapshotSerengeti.org）吸引公众参与，在这个平台上，公众可以帮助识别由相机陷阱拍摄的照片中的野生动物。随着人类活动的变化导致世界范围内大型食肉动物的持续减少，对生态系统稳定性的研究变得越来越重要，公众参与研究也是如此。更具体地说，这项研究将通过比较两个南非保护区有狮子和没有狮子的斑点鬣狗、豹子和猎豹的分布和数量大小，来测试塞伦盖蒂正在进行的一项捕食者研究的预测。例如，如果没有狮子，豹子的数量可能会增加，或者鬣狗可能会占据主要的河流栖息地。这种类型的反应是意料之中的，因为哺乳动物捕食者之间的重叠通常是最小的；相反，抑制似乎主要是通过直接攻击和大规模回避反应来调节的，这种反应将从属物种从大部分景观中取代。在传统的捕食者-猎物系统中，这种捕食风险的非消耗效应（NCE）产生了一种“恐惧景观”，这对捕食者-猎物动态比实际捕食更重要。例如，它可以成为营养级联背后的驱动力。然而，nce在驱动种群动态中的作用几乎只在小规模的捕食者-猎物系统中进行了研究。这个项目调查了nce在推动非洲大型食肉动物协会中顶端-中掠食者共存中的作用。研究的目的是：(1)比较大尺度位移对狮子与中掠食性动物共存的影响；(2)评价多时空尺度景观结构和行为回避对狮子与中掠食性动物共存的调节作用。预测复杂景观将通过最小化大规模位移来促进精细尺度的分区，从而实现共存。

This project explores the population dynamics of large African predators, asking how spotted hyenas, leopards, and cheetahs are able to live with lions, given that lions frequently harass and kill these smaller predators. Investigators will integrate data from surveys of lions with data from camera traps to determine how hyenas, leopards, and cheetahs distribute themselves across the landscape with respect to lions, and how differences in habitat use enable these species to coexist with and without lions. Understanding how predators coexist is important for understanding how large ecosystems function. Recent research has emphasized the profound effects that top predators can have on ecosystems; disrupting predator populations can destabilize natural systems in unexpected ways. The ability to predict how and why destabilization occurs is a necessary first step to preventing the ecological collapse of ecosystems with many types of predators. This project will engage the public through a citizen science platform (www.SnapshotSerengeti.org) in which members of the public help identify wild animals in photographs taken by camera traps. As anthropogenic change drives the continued decline of large predators around the world, research on ecosystem stability becomes increasingly relevant, as does public engagement in research.More specifically, this study will test predictions from an ongoing predator study in the Serengeti by comparing distributions and population sizes of spotted hyenas, leopards, and cheetahs across two South African reserves with and without lions. For example, without lions, leopard numbers may higher or hyenas may occupy prime riverine habitats. This type of response is expected because overlap between mammalian predators is typically minimal; instead, suppression appears to be mediated primarily through direct aggression and a large-scale avoidance response that displaces subordinate species from large portions of the landscape. In traditional predator-prey systems, this non-consumptive effect (NCE) of predation risk creates a "landscape of fear" that can be more important for predator-prey dynamics than actual predation. It can, for example, be the driving force behind trophic cascades. However, the role of NCEs in driving population dynamics has been almost exclusively investigated in small scale predator-prey systems. This project investigates the role of NCEs in driving apex-mesopredator coexistence in a guild of large African carnivores. The research has two aims: (1) to compare effects of large-scale displacement in driving lion-mesopredator coexistence, and (2) to evaluate the role of landscape structure and behavioral avoidance at multiple spatial and temporal scales in mediating lion-mesopredator coexistence. It is predicted that complex landscapes will facilitate fine-scale partitioning and thus coexistence by minimizing large-scale displacement.