Evaluating fisheries management options under large systematic changes in predator-prey interactions

评估捕食者-被捕食者相互作用发生重大系统变化下的渔业管理方案

• 批准号: RGPIN-2014-06145
• 负责人: McAllister, Murdoch
• 金额: $ 1.97万
• 依托单位: University of British Columbia
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=631614
• 关键词: Evaluating; fisheries; management; options; under

The quantitative models most commonly applied to provide fisheries management advice presume stability in ecological conditions governing fish population dynamics over long periods of time. In many regions there have been very large systematic trends in key species that prey on fishes and large fluctuations in key prey species. There has been considerable theoretical modeling research into studying the possible impacts of predator-prey interactions on commercially and recreationally valuable species. However, there has been relatively little attention given to developing stock assessment modeling approaches and management strategy evaluation (MSE) approaches that can offer direct advice to fisheries managers and policy makers in situations where there have been large apparent changes in key prey and predator species of key recreational and commercial fishes. I seek to investigate the influence of systematic changes in predator-prey interactions on fish population dynamics for a variety of Canadian fisheries in which there appears to have been substantial changes in the prey and predator populations. I will do so using a MSE approach in which I will build new population dynamics models of fish populations that account for the possible influence of changes in predator and prey populations in a number of Canadian fisheries where there have been substantial recent changes in key predator and/or prey species populations. I will seek to test hypotheses about the possible effects of changes in predator species abundance and predation rates on natural mortality rates and changes in prey species abundance on changes in growth rates for these fish populations. The long-term objective of my proposed research program is thus to investigate the influence of predator-prey interactions on fish populations using the framework of management strategy evaluation (MSE). I seek to develop population dynamics models, use Bayesian statistical techniques to test hypotheses about the influence of predator-prey interactions on the population dynamics of harvested fish populations and apply these models in MSEs to identify policy options that are robust to scenarios for plausible changes in future predation rates and prey availability. I plan to test the hypotheses that large systematic changes in (a) pinniped (e.g., seal species) population abundance and (b) forage species availability will modify the influence of fisheries exploitation on the population dynamics of harvested fish populations via changes in, e.g., growth and natural mortality rates (M). To undertake the research I will investigate how (1) spatial heterogeneity and historic and possible future trends in predation risk and the abundance of prey species can jointly modify (a) the population dynamics, (b) the maximum sustainable yield (MSY) reference points that are commonly used to guide policy advice, and (c) the suitability of different management approaches for a variety of harvested fish species. In addition I will investigate (2) how management approaches can be designed to adapt to systematic changes in the abundance of key predator and prey that may modify a fish stock’s resilience to exploitation. I plan two case studies: Project #1: Using an MSE approach to evaluate policy options for chronically-depleted B.C. inside water rockfish stocks. Project #2: Using a MSE approach to evaluate policy options for an apex predator under large changes in forage species abundance: Lower Fraser River white sturgeon. In these case studies, scenarios on how systematic changes in key predator and prey populations can affect fish stocks will be assessed in order to identify fisheries monitoring and harvest control policy options that respond appropriately to such changes.

定量模型最常用于提供渔业管理建议，假定长期管理鱼类种群动态的生态条件下的稳定性。在许多地区，关键物种的系统趋势非常大，这些趋势会捕食鱼类和主要猎物中的大波动。有相当大的理论模型研究，用于研究捕食者 - 捕食者相互作用对商业和休闲有价值物种的可能影响。但是，在开发股票评估建模方法和管理策略评估（MSE）方法的关注相对较少的关注下，可以在关键的猎物和主要娱乐性和商业鱼类的关键猎物和捕食者物种发生较大外表变化的情况下为渔业经理和政策制定者提供直接建议。我试图研究捕食者 - 捕食者相互作用的系统变化对加拿大渔业的鱼类种群动态的影响，在这些渔业中，猎物和捕食者种群似乎已经发生了很大的变化。我将使用一种MSE方法来建立新的人群动态模型的鱼类种群，以解释许多加拿大渔业中捕食者和猎物种群变化的可能影响，在许多加拿大渔业中，关键捕食者和/或猎物种群最近发生了很大变化。我将寻求检验假设，以了解捕食者物种丰度变化的可能影响和预测率对自然死亡率的变化以及猎物物种丰度的变化对这些鱼类种群的生长速率变化的变化。因此，我提出的研究计划的长期目标是使用管理策略评估框架（MSE）研究捕食者 - 捕集互动的影响。我试图开发人口动态模型，使用贝叶斯统计技术来测试有关捕食者 - 捕集互动对收获鱼类种群种群动态的影响的假设，并将这些模型应用于MSE中，以识别对未来捕食率和猎物的合理变化方案的稳健选择的策略选择。我计划测试假设的假设，即（a）（例如，密封物种）种群丰度和（b）饲料物种的可用性大大变化将通过变化，例如生长和自然死亡率（M）来改变鱼类剥削对收获鱼类种群种群种群种群的影响。为了进行研究，我将研究（1）如何共同修改预测风险的空间异质性，历史性和可能的​​未来趋势，并且猎物的丰度如何共同修改（a）人口动态，（b）通常用于指导政策建议的最大可持续性产量（MSY）参考点，以及（c）对不同管理方法的适用性，用于不同的管理方法，这些杂草的适用于各种各样的种类种类繁多的物种。此外，我将研究（2）如何设计管理方法来适应关键捕食者和猎物的抽象变化，从而可以改变鱼类库存对剥削的弹性。我计划了两个案例研究：项目＃1：使用MSE方法评估卑诗省长期耗尽的政策选择。在水石鱼库存中。项目＃2：使用MSE方法评估饲料物种抽象的大变化，评估顶点捕食者的政策选择：下弗雷泽河白st鱼。在这些案例研究中，将评估有关关键捕食者和猎物种群的系统变化如何影响鱼类种群的方案，以确定渔业监测和收获控制政策选择，以适当响应这种变化。