From aquatic food webs to our tables: the influence of exotic invasion on nutritional provisioning and contaminants in sport fish

该项目的目标是将食物网分析工具和生态系统建模相结合，以了解入侵圆形虾虎鱼对圣劳伦斯河（SLR）水生食物网质量和汞生物积累的营养作用。该项目与圣劳伦斯河环境科学研究所（“河流研究所”；非政府组织）合作，将培养1名博士生和数名理学士。我们将利用食物网示踪剂：稳定同位素、脂肪酸和甲基汞营养转移，在9至30个站点的每个站点的8个食物网营养水平上解决上SLR的生态系统水平问题。这些指标将在跨越SLR上游三个河流湖泊（St. Francis湖、Lac St. Louis湖和Lac des Deux Montagnes湖）的溶解有机碳、营养物质和入侵负荷的空间环境梯度的地点进行测量，并将与圆形虾虎鱼入侵有关。在圣弗朗西斯湖，生态系统模型将运用历史和当代数据来解决长尾贻贝和圆虾虎鱼入侵如何改变从初级生产者到水鸟的生物和物理化学特性。该合作伙伴将提供有关鱼类生态和食物网中汞转移的专业知识和基础设施支持，并分享圣弗朗西斯湖安大略省东部部分的历史数据。Upper SLR拥有经济上重要的运动鱼产业，联盟的研究项目将提供有关多种压力源如何在该生态系统中对污染物负荷和运动鱼的适应性进行相互作用的信息。研究成果将加强河流研究所与该组织的创始人和SLR的核心利益相关者的社区伙伴关系，如阿克韦塞内的莫霍克人。更广泛地说，该项目将深入了解外来入侵和其他环境压力因素如何相互作用，影响污染物负荷和人类运动鱼的营养供应。联盟的研究项目可能会影响政府关于运动鱼消费指导方针的政策，以平衡五大湖和SLR的汞暴露风险和营养供应的好处。

The project goal is to integrate food web analytical tools and ecosystem modelling to understand the trophic role of the invasive round goby fish on aquatic food web quality and Hg bioaccumulation in the St. Lawrence River (SLR). The project is a partnership with the St. Lawrence River Institute of Environmental Sciences ('The River Institute'; non-government organisation) and it will train 1 PhD student + several BSc students. We will address the ecosystem-level problem in the Upper SLR using food web tracers: stable isotopes, fatty acids, and MeHg trophic transfer, at 8 trophic levels of the food web per site, across 9 to 30 sites. These metrics will be measured at sites that span spatial environmental gradients in dissolved organic carbon, nutrients, and invasion load across three fluvial lakes of the Upper SLR (Lake St. Francis, Lac St. Louis, et Lac des Deux Montagnes), and will be related with round goby invasion. In Lake St. Francis, ecosystem models will be applied to address how dressenid mussel and round goby invasion have modified the biological and physicochemical properties from primary producers to aquatic birds, using both historical and contemporary data. The partner will provide expertise and infrastructural support on fish ecology and mercury transfer in the food web, as well as share historical data on the eastern Ontario section of Lac St. Francis. The Upper SLR has an economically important sportfish industry, and the Alliance research project will provide information about how the interplay of multiple stressors plays out for contaminant loads and fitness of sportfish in this ecosystem. The research outcomes will strengthen community partnership of The River Institute with founders of the organisation and core stakeholders in the SLR, such as The Mohawks of Akwesasne. More generally, the project will provide insight into how the interplay of exotic invasion and other environmental stressors play out for contaminant loads and nutrient provisioning of sportfish for people. The Alliance research project could impact government policy on guidelines for sportfish consumption for balancing the risks of mercury exposure with the benefits of nutritional provisioning in the Great Lakes and the SLR.