Mackerel is a fast-swimming fish common in the Northeast Atlantic, from Northwest Africa to the Barents Sea and to the west of Iceland in the Norwegian Sea. In summer and early autumn, the mackerel swim in schools along the Norwegian coast and in Skagerrak, the North Sea and the Norwegian Sea. The mackerel spawn in this area in early summer. Mackerel can reach a length of up to 66 cm, but are rarely longer than 40 cm. Its life span is up to 20 years.
The mackerel fishing season is from April to November, and commercial mackerel fishing mainly takes place in autumn. Mackerel is sold fresh, as frozen fillets, and as whole fish. There are many mackerel products, such as smoked and tinned mackerel and mackerel spread in tomato sauce.
Mackerel is one of the species that contains the most marine omega-3, but this varies depending on the season. In spring, mackerel has a low fat content of around three per cent, while in autumn, it can be up to more than 30 per cent. Mackerel is also a good source of vitamin D.
Content of undesirable substances
Mackerel generally contains low levels of both heavy metals and organic pollutants (POPs), and it is safe to eat.
NIFES has mapped undesirable substances in mackerel through thorough surveillance studies known as baseline studies. In the period 2007–2009, 1166 samples of individual mackerel were taken from 42 different positions, mostly in the North Sea, but also some from Skagerrak, the Norwegian Sea and the area west of Scotland.
Monitoring of undesirable substances in mackerel is now conducted in the North Sea every third year during the mackerel fishing season in autumn. Annual mackerel samples are taken in the Skagerrak.