Advancing spatio-temporal stock assessment models to integrate high-resolution seafloor mapping data in order to achieve sustainable harvest strategies for Canadian shellfish

海洋是加拿大文化、环境、公共卫生和经济的一个组成部分。海洋经济雇用了超过315,000名加拿大人，每年为国内生产总值（GDP）贡献超过260亿美元。加拿大大西洋的商业渔业主要由底栖贝类建造，2019年价值超过30亿美元。将空间信息纳入这些贝类种群的评估和管理的重要性早已得到认识。由于底栖贝类种群的密度分布与基质类型密切相关，因此海底生境图可以较好地反映底栖贝类种群的密度分布。这些地图与地理空间渔业数据相结合，具有巨大的潜力，可以提高我们对贝类种群动态和捕捞响应的空间格局和复杂性的理解。Clearwater海产品公司（Clearwater）、E'sukutimkewey和加拿大渔业和海洋部（DFO）之间的伙伴关系的目标是：A)开发将高分辨率数据流整合到下一代时空种群评估模型所需的统计框架和支持软件；B)通过纳入恢复和其他相关过程的时空变化的新知识，为底栖贝类（和其他）物种制定更可持续的捕捞策略。以北极面蛤（Mactromeris polynyma）为案例研究，这一伙伴关系将产生以下结果和影响：1)将高分辨率环境数据全面整合到种群评估模型和相关的收获战略过程中；2)对设定可持续清除水平有更大的信心；3)更好地理解如何实施基于生态系统的轮捕战略；4)将知识和技术转让给加拿大各地的种群评估科学家和渔业管理者。这将直接促成《渔业法》（正式法案C-68）中新的鱼类种群规定对渔业科学的额外需求。

The ocean is an integral part of Canada's culture, environment, public health and economy. The ocean economy employs more than 315,000 Canadians and contributes more than $26 billion of gross domestic product (GDP) each year. Atlantic Canada's commercial fishery is built primarily from benthic shellfish, valued at over $3 billion in 2019. The importance of incorporating spatial information into the assessment and management of these shellfish populations has long been recognized. Due to the strong association with substrate type, density distributions of benthic shellfish stocks can be relatively well represented by seafloor habitat maps. These maps, combined with geospatial fisheries data, have tremendous potential to improve our understanding of the spatial patterns and complexities of shellfish population dynamics and responses to fishing. The goals of this partnership between Clearwater Seafoods (Clearwater), E'sukutimkewey, and Fisheries and Oceans Canada (DFO) are to: A) develop the statistical framework and supporting software needed to integrate high-resolution data streams into the next generation of spatio-temporal stock assessment models; and B) devise more sustainable harvest strategies for benthic shellfish (and other) species by incorporating new knowledge of spatio-temporal variability in recovery and other relevant processes. Using Arctic surfclam (Mactromeris polynyma) as a case study, this partnership will give rise to the following outcomes and impacts: 1) full integration of high-resolution environmental data into stock assessment models and associated harvest strategy processes; 2) greater confidence in the setting of sustainable removal levels; 3) better understanding of how ecosystem-based rotational fishing strategies can be implemented; and 4) knowledge- and technology-transfer to stock assessment scientists and fisheries managers across Canada. This will directly contribute to the additional demands for fisheries science under the new Fish Stocks Provisions of the Fisheries Act (Formally Bill C-68).