Wilson Juliet S E, McGill Rona A R, Steingrund Petur, Trueman Clive N
Ocean and Earth Science, University of Southampton, Southampton, UK.
Marine Management Organisation, Environment Agency Romsey Office, Romsey, UK.
Rapid Commun Mass Spectrom. 2025 May;39 Suppl 1(Suppl 1):e9861. doi: 10.1002/rcm.9861. Epub 2024 Jul 22.
Increasing demand for fish and seafood means that the traceability of marine products is becoming ever more important for consumers, producers and regulators. Highly complex and globalised supply networks create challenges for verifying a stated catch region. Atlantic cod is one of the most commercially important species in the northeast Atlantic. Several regional fisheries supply cod into the trade network, of which some are at greater risk of overexploitation than others. Tools allowing retrospective testing of spatial origin would significantly assist sustainable harvesting of fish, reducing incentives for illegal fishing and fraud.
Here, we investigate whether stable isotope ratios of carbon, nitrogen and sulphur can be used to retrospectively identify the catch region of Atlantic cod (Gadus morhua). We measured the isotopic composition of muscle tissue from 377 cod from 10 catch regions across the northeast Atlantic and then applied three different assignment methods to classify cod by region of most likely origin. The assignment method developed was subsequently tested using independently sourced, known-origin samples.
Individual cod could be traced back to their true origin with an average assignment accuracy of 70-79% and over 90% accuracy for certain regions. Assignment success rates comparable to those using genetic techniques were achieved when assigning among restricted and pre-selected regions. However, assignment accuracy to the fishery region estimated from independent samples across the whole geographic range of cod averaged ~25% overall, highlighting the need for careful application of isotope-based approaches.
Stable isotope techniques can provide effective tools to test for origin in Atlantic cod, but not all catch regions are isotopically distinct. Stable isotopes could be combined with genetic techniques to result in higher assignment accuracy than could be achieved using either method independently. Assignment potential can be estimated from reference datasets, but estimates of realistic assignment accuracy require independently collected data.
对鱼类和海鲜的需求不断增加，这意味着海产品的可追溯性对消费者、生产者和监管机构而言变得愈发重要。高度复杂且全球化的供应网络给核实声称的捕捞区域带来了挑战。大西洋鳕鱼是东北大西洋最具商业价值的物种之一。多个区域渔业向贸易网络供应鳕鱼，其中一些渔业面临的过度捕捞风险高于其他渔业。能够对空间来源进行追溯性检测的工具将极大地有助于鱼类的可持续捕捞，减少非法捕捞和欺诈行为的动机。
在此，我们研究碳、氮和硫的稳定同位素比率是否可用于追溯识别大西洋鳕鱼（鳕属）的捕捞区域。我们测量了来自东北大西洋10个捕捞区域的377条鳕鱼肌肉组织的同位素组成，然后应用三种不同的分配方法按最可能的起源区域对鳕鱼进行分类。随后使用独立来源的已知起源样本对所开发的分配方法进行了测试。
个体鳕鱼能够追溯到其真实起源，平均分配准确率为70 - 79%，某些区域的准确率超过90%。在受限和预先选定的区域之间进行分配时，实现了与使用遗传技术相当的分配成功率。然而，在鳕鱼整个地理范围内对独立样本估计的渔业区域的分配准确率总体平均约为25%，这凸显了谨慎应用基于同位素方法的必要性。
稳定同位素技术可为检测大西洋鳕鱼的来源提供有效工具，但并非所有捕捞区域在同位素上都有明显差异。稳定同位素可与遗传技术相结合，从而实现比单独使用任何一种方法更高的分配准确率。可从参考数据集中估计分配潜力，但实际分配准确率的估计需要独立收集的数据。
