Atlantic mackerel

Scientific: Scomber scombrus. English: Atlantic mackerel. Icelandic: Makríll. For more languages see the Marine Animal Dictionary.

Biology and distribution

The mackerel is a streamlined and fast swimming fish known from extensive migrations. It grows rapidly and is usually around 15 cm in the first autumn after spawning (in spring). It reaches sexual maturity at the age of 2 to 3, then around 30 cm long. Common size for adults is from 35 cm to 45 cm, but it can reach 60 cm in length. The mackerel feeds on a variety of pelagic animals, mostly crustaceans and fish juveniles.

The Atlantic mackerel occurs from the northeast coast of USA, up to Newfoundland Island. On the eastern side it is found off Morocco, in the Mediterranean sea and all the way up to the Barents Sea, although only occasionally. Three stocks are recognized in the north east Atlantic. The southern stock spawns in Spanish and Portuguese waters, the western stock spawns in the Bay of Biscay and around Ireland and the third stock spawns in the North Sea.

The mackerel has not previously been known to spawn in Icelandic waters but migrates there occasionally and can then be found all around the country. It seems clear from archives that this happens regularly as large amount of mackerel were reported for many years in a row around 1900, and during the warm period from 1926 to 1945 and sporadically in between and after. It is also clear that it is now mass migrating into the Icelandic EEZ due to the current warm oceanic conditions.

Catch, fishing methods and processing

Some catch has been reported in Icelandic waters in the past, probably bycatch in herring fisheries. Icelandic boats also fished for mackerel in the North Sea from 1967 to 1976. For about 20 years after that, Icelandic boats did not report any catches until after 2006. Since that catches have increased significantly.

The mackerel is a valuable pelagic fish and most of the catch is for human consumption. The mackerel is fished with midwater trawl or purse seines, iced or frozen at sea and then processed after landing. The fillets are canned, smoked or sold fresh.

Stock status (from the Marine Research institute)

International landings of mackerel (Scomber scombrus ) in the Northeast Atlantic in 2011 are estimated at 927 000 t. Since the mid 2000s mackerel has been observed in the Icelandic EEZ, which has led to a direct fishery in the last years. In 2011 the Icelandic landings were 159 000 t. The spawning stock increased from 2003 to 2009 but has decreased since then and the estimated spawning stock in 2012 is about 2.7 million t. ICES will assess the stock in the autumn and release its advice for 2013 in Octo- ber 2012. A multilateral agreement on sharing the mackerel quotas has not been reached among the nations participating in the fishery.

References and further information

• Ástþórsson, Ó.S., Sigurðsson, Þ. and Sveinbjörnsson, S. 2009. Makríll á Íslandsmiðum / Mackerel in Icelandic waters. In: Þættir úr vistfræði sjávar 2009. Environmental conditions in Icelandic waters 2009.Hafrannsóknir 152. 53 p.
• Friðriksson, Á. (1944). Makríllinn við Ísland (the mackerel in Icelandic waters). Náttúrufræðingurinn, 14: 138-142. (in Icelandic)
• Jónsson, G., & Pálsson, J. (2006). Íslenskir fiskar (Icelandic fishes). Reykjavík, Iceland. 336 p (in Icelandic)

Hreiðar Þór Valtýsson, University of Akureyri