Impacts of Southern Ocean warming on marine connectivity: Integrating oceanographic modelling with molecular ecology and developmental biology

南大洋变暖对海洋连通性的影响：将海洋学模型与分子生态学和发育生物学相结合

• 批准号: NE/H023704/1
• 负责人: Gary Carvalho
• 金额: $ 32.35万
• 依托单位: Bangor University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2011
• 资助国家: 英国
• 起止时间: 2011 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FH023704%2F1
• 关键词: Impacts; Southern; Ocean; warming; marine

General Summary: Our work brings together data on developmental rate of fish larvae, population genetics, ocean circulation and the environment (specifically temperature) to generate predictions of recruitment that can be tested. This provides us with a powerful tool for tackling the uncertainty that characterizes the dynamics of wild populations in a rapidly changing world. Many fish populations, as all species living in nature, are exposed to a wide variety of changes in the environment that determine their abundance and distribution. Some changes are natural and include such things as alterations in food supply or number of mates, while others are largely driven by man-made activities, of which climate change and exploitation are two major types. Since fish form a major component of natural ecosystems in providing food for many other animals, and are predators of many groups, and since they also form a major source of human food globally, it is important that we estimate the role of various environmental changes on their dynamics, especially as many fish populations have recently collapsed, or are only in early stages of recovery. Here we examine, using several fish species from a well characterised region of the Antarctic, the potential effect that an increase in temperature might have on the numbers of fish entering the adult population ('recruitment'), and more specifically the rate at which their larvae develop. It is well established that at higher temperatures, larvae that rely on yolk resources for nutrition will exhaust these supplies more quickly at higher temperatures, meaning they may not reach appropriate feeding grounds in time to develop into adults. In such circumstances, fewer young will recruit to the next generation of individuals, and since dispersal among sites will be reduced, populations would be expected to lose connectivity, which has follow-on effects on population and ecosystem resilience. We will examine how likely such effects are by observing fish larvae of several species differing slightly in their life history larval characteristics, and compare their rates of development in relation to fluctuations in temperature. We test whether higher temperatures do indeed lead to faster development by two means: (1) with live larvae acclimated to different temperatures regimes within a season, and (2) with archived larval specimens sampled from the wild across multiple years in which developmental temperature regimes varied. We then take this information and add it to Individual Based Models incorporating ocean circulation and biological characteristics of each species, thus creating species-specific biophysical models. This allows us to test whether any changes in rate of development will influence the likelihood of larvae reaching appropriate feeding grounds and recruiting to the adult population. Model predictions of dispersal for the present-day will be validated by comparison with inferred dispersal from genetic analyses, and an assessment of dispersal variability due to interannual oceanographic variability will allow the effects of increased temperature to be placed in context. It will then be possible to make predictions about the likely effects of the predicted increases in temperature in the area on fish recruitment as a component of climate change. Such information is important since climate records from the Antarctic show that the waters of the Antarctic are warming more rapidly than the global ocean as a whole. Not only is this significant for much of the biodiversity that is unique to the Antarctic, but the Southern Ocean is known to influence climates globally. Ultimately, our integration of environmentally relevant data taken from nature, with genetically validated 'biophysical' models will enable a more realistic projection of the impact of ocean warming on marine species and ecosystems.

一般总结：我们的工作汇集了有关鱼苗发育速率、种群遗传学、海洋环流和环境（特别是温度）的数据，以生成可以测试的招募预测。这为我们提供了一个强大的工具，用于解决在快速变化的世界中野生种群动态的不确定性。许多鱼类种群，因为所有物种生活在自然界中，暴露于各种各样的环境变化，决定了他们的丰度和分布。有些变化是自然的，包括食物供应或配偶数量的改变，而另一些变化则主要是由人为活动驱动的，其中气候变化和剥削是两种主要类型。由于鱼类是自然生态系统的主要组成部分，为许多其他动物提供食物，并且是许多群体的捕食者，而且它们也是全球人类食物的主要来源，因此我们必须估计各种环境变化对其动态的作用，特别是因为许多鱼类种群最近已经崩溃，或者只是处于恢复的早期阶段。在这里，我们研究，使用几种鱼类从南极洲的一个很好的特征区域，温度的增加可能对进入成年人口（“招聘”）的鱼的数量的潜在影响，更具体地说，他们的幼虫发育的速度。众所周知，在较高的温度下，依赖蛋黄资源获得营养的幼虫在较高的温度下会更快地耗尽这些供应，这意味着它们可能无法及时到达适当的摄食场所发育成成虫。在这种情况下，招募下一代个体的年轻人将减少，而且由于地点之间的分散将减少，预计种群将失去连通性，这对种群和生态系统的复原力产生后续影响。我们将通过观察几个物种的幼体在其生活史幼虫特征方面略有不同，并比较它们的发育速率与温度波动的关系，来研究这种影响的可能性。我们通过两种方式测试较高的温度是否确实会导致更快的发育：（1）在一个季节内适应不同温度制度的活幼虫，以及（2）从野外多年采集的存档幼虫标本，其中发育温度制度各不相同。然后，我们将这些信息添加到基于个体的模型中，结合海洋环流和每个物种的生物特征，从而创建特定物种的生物物理模型。这使我们能够测试发育速度的任何变化是否会影响幼虫到达适当的觅食地和招募成年种群的可能性。将通过与遗传分析推断的扩散进行比较来验证模型对目前扩散的预测，并评估由于年际海洋变化引起的扩散变化，以便将温度升高的影响置于背景中。这样就有可能预测该地区预计的气温上升对鱼类补充的可能影响，这是气候变化的一个组成部分。这类信息很重要，因为南极的气候记录表明，南极沃茨的变暖速度比全球海洋整体的变暖速度更快。这不仅对南极特有的生物多样性意义重大，而且众所周知，南大洋影响着全球气候。最终，我们将从自然界获取的环境相关数据与经过遗传验证的“生物物理”模型相结合，将能够更现实地预测海洋变暖对海洋物种和生态系统的影响。

项目成果

Stepping stones to isolation: Impacts of a changing climate on the connectivity of fragmented fish populations.

• DOI: 10.1111/eva.12613
• 发表时间: 2018-07
• 期刊: Evolutionary applications
• 影响因子: 4.1
• 作者: Young EF;Tysklind N;Meredith MP;de Bruyn M;Belchier M;Murphy EJ;Carvalho GR
• 通讯作者: Carvalho GR

Oceanography and life history predict contrasting genetic population structure in two Antarctic fish species.

海洋学和生活史预测了两种南极鱼类的遗传种群结构对比。

• DOI: 10.1111/eva.12259
• 发表时间: 2015-06
• 期刊: Evolutionary applications
• 影响因子: 4.1
• 作者: Young EF;Belchier M;Hauser L;Horsburgh GJ;Meredith MP;Murphy EJ;Pascoal S;Rock J;Tysklind N;Carvalho GR
• 通讯作者: Carvalho GR

Physical and behavioural influences on larval fish retention: contrasting patterns in two Antarctic fishes

• DOI: 10.3354/meps09908
• 发表时间: 2012-09
• 期刊: Marine Ecology Progress Series
• 影响因子: 2.5
• 作者: E. Young;J. Rock;M. Meredith;M. Belchier;E. Murphy;G. Carvalho