Large-Scale Phenomena in Anti-Predator Behavior: On the Consequences of Putting Predators Back Into Predator-Prey Interactions

反捕食者行为中的大规模现象：关于让捕食者重新进入捕食者-猎物相互作用的后果PI-Steven L.Lima大多数关于动物反捕食者行为的研究集中在猎物对捕食者施加的环境水平的捕食风险做出反应的小区域。这种趋势更多地关注猎物的行为，而不是捕食者，而捕食者通常被视为猎物的风险来源，而不是行为互动的积极参与者。这种小规模的视角揭示了许多关于行为捕食者-猎物相互作用的信息，但它错过了存在于更大空间尺度上的一整类行为相互作用。要欣赏这些大规模的相互作用，人们必须考虑生态景观的规模，或者说是一个面积大得多的区域--这个规模比行为生态学家通常认为的要大得多。人们还必须让捕食者成为行为互动的积极参与者，从而让它们回到画面中。更具体地说，这项拟议的工作是由一个简单的问题推动的：是什么驱使动物在一片风景中移动？目前(小规模的)共识认为，猎物的运动会吸引捕食者，因此猎物的运动必须反映寻找新的食物来源等的需要。然而，模拟模型的结果表明，捕食者和猎物可能参与了一个大规模的外壳游戏，其中捕食者经常移动以寻找难以捉摸的猎物，猎物在觅食地点之间移动以保持难以捉摸。此外，如果给定区域的猎物相对难以定位，那么捕食者会将注意力集中在其他地方更可预测的猎物上，结果是这些可预测的猎物可能会发起更大的运动来躲避捕食者。猎物之间的这种间接相互作用(通过它们对捕食者行为的影响)代表了一个相关的大规模现象：捕食者传递效应。在其他情况下，捕食者可能会避免不断攻击特定位置的猎物，以努力使它们在长期内更容易被捕获。这种掠夺行为代表了另一种大规模效应：捕食者对猎物的管理。对这些大尺度现象的进一步理论探索是拟议工作的一个重要特点。拟议的大部分工作涵盖了对这些大尺度行为相互作用的实证探索。这项工作的重点是冬季小鸟的概念上的重要范例，在这个范例中，小鸟必须在严酷的冬季和食鸟的鹰的捕食性攻击中生存下来。这项任务需要进行大量的基础生物学研究，因为人们对小型越冬鸟类或鹰的大规模活动知之甚少。将(通过无线电跟踪技术)在许多平方公里的研究区域内跟踪鹰和它们的猎物的日常活动。将建立关于鹰和猎物家的范围、大小和移动的基本信息。利用在整个研究区域建立的食物操纵点，捕食鸟的分布和空间可预测性将被实验性地改变。这些食物站点将被操纵(建立和撤回)，以测试关于外壳游戏、捕食者传递效应和捕食者对猎物管理的预测。在大空间尺度上进行行为研究面临着独特的挑战，但这种工作代表着研究捕食者-猎物相互作用的重要一步，最终可能会对整个生态系统有更多的了解。

Large-scale phenomena in anti-predator behavior: on the consequencesof putting predators back into predator-prey interactionsPI - Steven L. LimaMost studies on the anti-predator behavior of animals focus on a small area in which prey respond to an ambient level of predation risk imposed by predators. The tendency has been to focus more the behavior of prey rather than predators, and the latter have usually been treated merely as a source of risk to prey rather than active participants in the behavioral interaction. This small-scale perspective has revealed much about behavioral predator-prey interactions, but it has missed an entire class of behavioral interactions that exist at larger spatial scales. To appreciate these large-scale interactions, one must think on the scale of an ecological landscape, or an area many km2 in extent-a scale much larger than usually considered by behavioral ecologists. One must also put predators back into the picture by allowing them to be an active participant in the behavioral interaction. More specifically, the proposed work is motivated by a simple question: what drives the movement of animals across a landscape? The present (small-scale) consensus holds that movement by prey attracts predators, hence movement by prey must reflect a need to find new sources of food, etc. However, the results of a simulation model show that predator and prey may be involved in a large-scale shell game, in which predators move frequently in search of elusive prey, and prey move among feeding sites to remain elusive. Furthermore, if prey in a given area are relatively difficult to locate, then predators will focus their attention elsewhere on more predictable prey, with the result that these predictable prey may initiate greater movement to avoid predators. This indirect interaction among prey (through their effect on the predator's behavior) represents a related large-scale phenomenon: the predator pass-along effect. Under other circumstances, predators might avoid constantly attacking prey at a particular location in an effort to render them more catchable in the long-run. Such predatory behavior represents another large-scale effect: prey management by predators. The further theoretical exploration of these large-scale phenomena is an important feature of the proposed work.Much of the proposed work covers an empirical exploration of these large-scale behavioral interactions. This work focuses on the conceptually important paradigm of the small bird in winter, in which small birds must survive both the rigors of winter and the predatory onslaught of bird-eating Accipiter hawks. This task requires much basic biological research, as very little is known about the large-scale movements of small wintering birds or Accipiter hawks. The daily movements of hawks and their avian prey will be followed (via radiotracking techniques) over study areas many km2 in extent. Basic information will be established on hawk and prey home range sizes and movements. Using food manipulation sites established throughout a study area, the distribution and spatial predictability of prey birds will be altered experimentally. These food sites will be manipulated (established and withdrawn) in order to test predictions concerning shell games, predator pass-along effects, and prey management by predators. Conducting behavioral research at a large spatial scale presents unique challenges, but such work represents an important step in the study of predator-prey interactions, one that may ultimately shed much light on ecological systems in general.