Neophobia and the assessment of predation risk in aquatic systems.

由于捕食的非消耗性影响，猎物往往被迫在觅食、求偶、领土防御等关键活动之间取舍，以加强风险评估和躲避捕食者。能够平衡这些权衡的关键是对当地捕食威胁的可靠评估。然而，在生态不确定(定义为关于当地捕食威胁的不完全信息造成的模糊)的情况下，很难进行这种风险评估。由于捕食风险的空间和时间变化，或捕食者行会密度和/或多样性的局部变化，可能会产生不确定性。随着不确定性的增加，对当地威胁做出不恰当反应的可能性可能会增加；这放大了捕食的非消耗性影响的成本。为了应对风险中的不确定性，猎物可能依赖于获得的信息(学习)，以实现足够的行为可塑性，以应对各种威胁。然而，学习是有代价的，因为猎物必须在最初与捕食者相遇后幸存下来，才能获得与生态相关的信息。我们的新恐惧症捕食者识别模型认为，对新线索的反应是对不确定的捕食风险的典型塑料反应。对未知捕食者线索的反应可能会为天真的猎物提供一种适应机制，以避免与有充分记录的习得捕食者识别相关的“第一次接触”成本，同时仍确保有足够的行为灵活性来应对不确定的威胁。我们建议的第一个目标是测试生态约束和生存价值对新恐惧症捕食者识别的影响。这些数据将使我们能够基于对慢性威胁和短期行为决策的综合适应，开发出一个新恐惧症的通用模型。拟议的实验(以及从收集的数据中可能产生的其他实验)旨在探索个体对风险的感知、捕食风险和捕食者多样性在获得和保持对新的捕食者线索的新恐惧症反应中所起的作用。我们的第二个目标是应用我们的新恐惧症模型和与生态相关的学习来提高孵化场饲养的鱼类放养后的存活率。作为重建或维持自然种群的持续努力的一部分，每年都有数百万只孵化场饲养的幼体鲑鱼被放养到自然水道中。然而，缺乏经验和孵化场所选择的综合影响导致放养后的存活率很低。一种普遍提倡的提高放养后生存的方法是生活技能培训，包括在放养之前调节孵化场饲养的猎物识别常见捕食者。只有少数几项研究直接测试了生活技能训练的“现实世界”益处，结果好坏参半。主要使用基于现场的方案，我们将评估生活技能培训的可行性，以提高预先放养的条件训练计划的成功。其影响在于将行为生态学应用于提高孵化养殖场鱼类放养后的存活率。孵化场养殖的鱼类(特别是鲑鱼)放养后存活率的增加将对正在进行的和未来的保护和恢复计划产生直接好处。除了加强商业和休闲渔业的努力外，我们的成果还将有利于保护当地濒危鱼类种群的努力。

As a result of the nonconsumptive effects of predation, prey are often forced to trade-off critical activities such as foraging, courtship, territorial defence, in favour of increased risk assessment and predator avoidance. Key to the ability to balance these trade-offs is the reliable assessment of local predation threats. However, the ability to make such risk assessments is difficult under conditions of ecological uncertainty (defined as ambiguity resulting from imperfect information regarding local predation threats). Uncertainty may arise as a result of spatial and temporal variability in predation risk or with local variability in density and/or diversity of the predator guild. As uncertainty increases, the chance of inappropriate responses to local threats likely increases; magnifying the costs of nonconsumptive effects of predation. In response to uncertainty in risk, prey may rely on acquired information (learning) in order to achieve sufficient behavioural plasticity to respond to variable threats. However, learning comes at a cost as prey must survive the initial encounter with a predator in order to acquire ecologically relevant information. Our model of neophobic predator recognition, argues that the response to novel cues is a phenotypically plastic response to uncertain predation risk. The response to unknown predator cues may provide naïve prey with an adaptive mechanism to avoid the ‘first encounter’ cost associated with the well-documented learned predator recognition while still ensuring sufficient behavioural flexibility to respond to uncertain threats. The first objective of our proposal is to test the ecological constraints and survival value shaping neophobic predator recognition. These data will allow us to develop a generalized model of neophobia based on the combined adaptations to chronic threats and short-term behavioural decisions. The proposed experiments (and others that may arise from the data collected) are aimed at exploring the role of individual perception of risk, predation risk and predator diversity play in the acquisition and retention of neophobic responses to novel predator cues. Our second goal is to apply our models of neophobia and ecologically-relevant learning to enhance post-stocking survial of hatchery-reared fishes. Each year, millions of hatchery-reared juvenile salmonids are stocked into natural waterways as part of ongoing efforts to re-establish or maintain natural populations. However, the combined effects of lack of experience and hatchery selection leads to poor post-stocking survival. One commonly advocated method to enhance post-stocking survival is life-skills training, including conditioning hatchery-reared prey to recognize common predators prior to stocking. Only a handful of studies have directly tested the ‘real-world’ benefits of life-skills training, with mixed to negative results. Using primarily field-based protocols, we will assess the feasibility of life-skills training to improve the success of pre-stocking conditioning programs. The impact lay in the application of behavioural ecology to the enhancement of post-stocking survival of hatchery-reared fishes. Increased post-stocking survival of hatchery-reared fishes (especially salmonids) will have direct benefits for ongoing and future conservation and recovery programs. In addition to the efforts to enhance commercial and recreational fisheries, our results will also benefit conservation efforts for locally endangered fish populations.