From genes to ecosystems: an eco-evolutionary assessment of alternative harvesting strategies and consequences for fisheries productivity

从基因到生态系统：替代捕捞策略的生态进化评估及其对渔业生产力的影响

• 批准号: 494015-2016
• 负责人: Fraser, Dylan
• 金额: $ 14.08万
• 依托单位: Concordia University
• 依托单位国家: 加拿大
• 项目类别: Strategic Projects - Group
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=602958
• 关键词: genes; ecosystems; eco; evolutionary; assessment

We will employ a novel, multidisciplinary approach to assess to what degree eco-evolutionary changes generated by common harvesting approaches affect fisheries productivity. We will blend emerging theory, concepts and new advances in population genomics, eco-evolutionary dynamics and community ecology to conduct a large scale harvest selection experiment based on experimentally-controlled depletions across a series of closed, natural trout populations. Our project will take advantage of the mandate of Parks Canada to actively restore previously fishless alpine lakes where non-native trout were introduced 80-100 years ago. Hence it provides an exceptional opportunity to conduct replicated depletion of natural populations of a socio-economically important fish species groups (salmonids) where they will be removed anyways. These depletions will be used to (i) explore several untested hypotheses about the effects of size-selective harvesting on fisheries productivity and ecosystem function and (ii) characterize the efficacy of an alternative harvesting approach to substantially reduce size-selective effects ('balanced harvesting'). Concurrently, the project will contribute to reaching ecosystem restoration targets using non-poison removal techniques, for one of Canada's most important heritage symbols - the magnificent Rocky Mountain lakes. Trout depletion will simulate (i) commonly occurring size-selective harvesting of large-sized individuals (4 lakes) and (ii) 'balanced harvesting', wherein mortality is distributed across the widest range of sizes in an ecosystem, in proportion to their natural productivity, with the aim that size-selectivity and associated evolutionary changes are minimized (4 lakes); 4 additional, non-depleted lakes will act as controls. Intense size-selective harvesting has taken place in a 13th lake since 2011 and affords a longer-term temporal assessment of genomic change associated with harvesting selectivity. Lakes will be of a similar characteristics and have had a negligible history of fishing prior to trout depletion. Pre- and post-depletion monitoring of a series of response variables/metrics at the gene, population, community and ecosystem levels will be conducted on multiple age-cohorts over successive years.

我们将采用一种新颖的多学科方法来评估常见捕捞方法产生的生态进化变化对渔业生产力的影响程度。我们将融合种群基因组学、生态进化动力学和群落生态学方面的新兴理论、概念和新进展，在一系列封闭的天然鳟鱼种群中基于实验控制的消耗进行大规模的收获选择实验。我们的项目将利用加拿大公园管理局的授权，积极恢复以前无鱼的高山湖泊，这些湖泊是 80-100 年前引入的非本地鳟鱼。因此，它提供了一个绝佳的机会，对具有社会经济重要意义的鱼类种群（鲑鱼）的自然种群进行重复性消耗，无论如何它们都将被清除。这些消耗将用于（i）探索关于尺寸选择性捕捞对渔业生产力和生态系统功能的影响的几个未经检验的假设，以及（ii）表征替代捕捞方法在大幅减少尺寸选择性效应（“平衡捕捞”）方面的功效。同时，该项目将有助于利用无毒去除技术实现加拿大最重要的遗产标志之一——壮丽的落基山湖泊的生态系统恢复目标。鳟鱼枯竭将模拟（i）常见的大型个体（4个湖泊）的尺寸选择性捕捞和（ii）“平衡捕捞”，其中死亡率按照其自然生产力的比例分布在生态系统中最广泛的尺寸范围内，目的是最大程度地减少尺寸选择性和相关的进化变化（4个湖泊）；另外 4 个未枯竭的湖泊将作为对照。自 2011 年以来，第 13 个湖泊进行了密集的尺寸选择性捕捞，并为与捕捞选择性相关的基因组变化提供了长期的时间评估。湖泊将具有类似的特征，并且在鳟鱼枯竭之前的捕捞历史可以忽略不计。将连续几年对多个年龄组进行基因、种群、群落和生态系统层面的一系列反应变量/指标的消耗前和消耗后监测。