Escaped farmed Atlantic salmon (Salmo salar) is considered a threat to wild salmon. In order to take action to reduce the impact of escapees, methods to distinguish escapees from wild fish and to trace them back to their origin are in demand. This paper gives an overview of available methods and discusses the impact on fish welfare, both in the short‐ and long‐term. Adipose fin clipping, freeze branding, different external and internal tags, as well as natural and chemical marks are considered. All marking procedures that involve handling of fish have an impact on fish welfare. Spraying with pigments and most externally attached tags significantly reduce the welfare, both on short‐term and long‐term perspectives. Although the use of natural or chemical marks, like exposure to stable isotopes via egg immersion or vaccination, involves no or no extra handling, subsequent analysis may require killing the fish after catch. Large‐scale marking with implanted or external tags could represent higher risks of human errors and reduced fish welfare, as opposed to small‐scale marking. In general, the knowledge about effects of marking on fish welfare is limited for most of the available methods, in particular regarding other effects than mortality and growth reductions.

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评价养殖鲑鱼的大规模标记方法以进行追踪：对鱼类福利的影响

逃脱的养殖大西洋鲑鱼（Salmo salar）被视为对野生鲑鱼的威胁。为了采取行动减少逃逸者的影响，需要一种将逃逸者与野生鱼类区分开来并将其追溯到其起源的方法。本文概述了可用的方法，并讨论了短期和长期对鱼类福利的影响。可以考虑脂肪翅片修剪，冻结商标，不同的内部和内部标签以及天然和化学标记。所有涉及鱼类处理的标记程序都会对鱼类的福利产生影响。从短期和长期的角度来看，喷涂颜料和大多数外部附着的标签会大大降低福利。尽管使用自然或化学标记，例如通过鸡蛋浸泡或接种疫苗而暴露于稳定的同位素中，都不需要或不需要额外的处理，随后的分析可能需要在捕捞后将鱼杀死。与小规模标记相反，带有植入标签或外部标签的大规模标记可能会带来更高的人为错误和降低鱼类福利的风险。通常，对于大多数可用的方法，关于标记对鱼类福利的影响的知识是有限的，特别是关于除死亡率和生长减少以外的其他影响。