In Europe, research surveys carried out by state governments provide the great majority of fishery-independent data. Member States (MS) in the European Union (EU) regularly conduct research surveys to provide the necessary data to assess the status of exploited fish stocks and to monitor the general condition of the marine ecosystem. In the surveys, samplings are carried out throughout the distribution range of the targeted fish species using standardized gears (e.g., trawls and seines) and other methods (e.g., hydroacoustics and underwater cameras). In the context of fish stock assessment, survey data are important because they provide indices that help tuning the stock assessment models (e.g., the index of fish abundance) and key information about the size and age distributions of the stock, the size-age relationships, the proportion of fish mature at each age, and information on reproductive performance of the stocks. However, research surveys have a number of shortcomings that include, for example, a high economic cost coupled with complex logistics and a long time required for processing the collected data. In addition, some of the parameters that are needed in stock assessment cannot be estimated from survey data for certain commercially important species. For instance, age is usually determined using hard structures (such as otoliths) in fish target species. However, for European hake, age cannot be determined accurately because there are many difficulties in interpreting the ring patterns of the otoliths. This highlights the need to look for alternative methodologies such as genomics, that have the potential of improving the data obtained from research surveys and hence, improve fish stock assessments. Considering this, we carried out a review of the bottom trawl research surveys in the EU with the purpose of: 1) identifying the current approaches for monitoring fishery resources and the ecosystem and 2) determining how genomic techniques can be used to improve survey data, taking into account the needs of current and future stock assessment in Europe.

中文翻译：

---

基因组方法在底拖网调查中的潜在用途，以改善欧洲的种群评估

在欧洲，州政府开展的研究调查提供了绝大部分与渔业无关的数据。欧盟 (EU) 成员国 (MS) 定期进行研究调查，以提供必要的数据来评估已开发鱼类的状况并监测海洋生态系统的总体状况。在调查中，使用标准化渔具（例如拖网和围网）和其他方法（例如水声学和水下照相机）在目标鱼类的整个分布范围内进行采样。在鱼类种群评估的背景下，调查数据很重要，因为它们提供了有助于调整种群评估模型的指数（例如，鱼类丰度指数）和有关种群大小和年龄分布、大小-年龄关系的关键信息, 每个年龄段成熟鱼的比例，以及有关种群繁殖性能的信息。然而，研究调查有许多缺点，例如，经济成本高，物流复杂，处理收集到的数据需要很长时间。此外，资源评估所需的一些参数无法从某些具有重要商业价值的物种的调查数据中估算出来。例如，通常使用鱼类目标物种的硬结构（例如耳石）来确定年龄。然而，对于欧洲无须鳕来说，由于耳石环纹的解释存在很多困难，因此无法准确确定年龄。这突出了寻找替代方法的必要性，例如基因组学，有可能改进从研究调查中获得的数据，从而改进鱼类种群评估。考虑到这一点，我们对欧盟的底拖网研究调查进行了审查，目的是：1) 确定当前监测渔业资源和生态系统的方法，以及 2) 确定如何使用基因组技术来改进调查数据，考虑到欧洲当前和未来库存评估的需要。