Over the span of a decade, genetic identification methods have progressively exposed the inadequacies of the seafood supply chain, revealing previously unrecognized levels of seafood fraud, raising awareness among the public, and serving as a warning to industry that malpractice will be detected. Here we present the outcome of the latest and largest multi‐species, transnational survey of fish labeling accuracy to date, which demonstrates an apparent sudden reduction of seafood mislabeling in Europe. We argue that recent efforts in legislation, governance, and outreach have had a positive impact on industry regulation. Coordinated, technology‐based, policy‐oriented actions can play a pivotal role in shaping a transparent, sustainable global seafood market and in bolstering healthier oceans.

Salmon have been widely publicized as a good dietary source of vitamin D, but recent data points to large variation in vitamin D content and differences between wild and farmed salmon. We aimed to: (1) investigate the content of vitamin D in Atlantic salmon (Salmo salar) in wild species caught in two different waters, (2) perform a 12-week feeding trial in farmed Salmo salar with 270–1440 µg vitamin D3/kg feed (4–20 times maximum level in the EU) and (3) conduct a review for the published data on the content of vitamin D in salmonids. Content of vitamin D3 in the fillet from wild salmon caught in the Baltic Sea and the North Sea was significantly different (p < 0.05), being 18.5 ± 4.6 µg/100 g and 9.4 ± 1.9 µg/100 g, respectively. In the farmed salmon the content ranged from 2.9 ± 0.7 µg vitamin D3/100 g to 9.5 ± 0.7 µg vitamin D3/100 g. Data from 2018 shows that farmed salmon contained 2.3–7.3 µg vitamin D3/100 g. Information on the content of vitamin D in wild and farmed salmonids is very limited, which calls for further research to ensure a sustainable production of salmon with adequate vitamin D.

Fatty fish are generally stated as having high vitamin D content and among these are salmon and trout. In the aquaculture industry of salmonids the two main species produced are Salmo salar (Atlantic salmon) and Onchorhynchus mykiss (rainbow trout). Published data have shown lower content of vitamin D in farmed than in wild species, but generally data on vitamin D in farmed salmon and rainbow trout are scarce. In commercial production facilities we aimed to study the variation of vitamin D in farmed salmon and rainbow trout prepared for sale to consumer. Thirteen organically produced salmon and 18 rainbow trout were sampled within the range 0.7-4.0 kg of gutted weight. All fish were ready for consumption, and analysed for content of vitamin D3, 25-hydroxyvitamin D3, and fat.Mean vitamin D3 content in salmon and rainbow trout was 1.6 ± 0.5, and 5.0 ± 2.3 µg/100 g, respectively. Compared to vitamin D3, the content of 25-hydroxyvitamin D3 was 11% and 3%, respectively. In farmed salmon a linear relationship with vitamin D3 being dependent on weight (P<0.05) as well as to fat content (P<0.05), while no similar relationship was found for farmed rainbow trout. Despite this, both species exhibit a linear correlation between fat and gutted weight (P<0.001).The results indicate that there is a difference in the storage of vitamin D between the two salmonids, as 25-found in the salmonids is challenging farmed salmon and farmed trout as an essential vitamin D source.