MACKEREL

Scomber scombrus

Characteristics

Mackerel is a fast swimming pelagic fish, which can be found in very large shoals close to the surface. It is a migratory fish sometimes covering long distances in a season and reaches a normal size of between 30-50cm after three years when it matures sexually.

Mackerel also form the feed of larger species like dogfish, sharks, tunny and dolphins and, when hunted, can reach great depths very quickly.

Habitat and Migration

Most of them overwinter on the bottom in the northern N Sea and to the south and west of the British Isles and do not feed during this rest period. In spring they begin to feed again on plankton sieved through the gill system while moving into the warmer upper water layers and by April-May are mostly in coastal waters with a temperature of around 11-14 C. Spawning takes place in May-June near the surface and the larvae do not leave the coastal area until autumn and in two years will have reached a size of 20cm.

After spawning, the adult mackerel begin to feed actively hunting for small herring, sprat and sand eels until they leave the coastal waters again in August-September.

The Catch

There are two main fisheries involving UK fishermen and they are the N Sea, which is a summer fishery, and the W Coast, which is an autumn/winter fishery. There is also a smaller fishery off the Cornish coast.

The fish are caught mainly by purse seine and midwater trawl. The purse seine enables the fish to be pumped on board and into refrigerated tanks, a process which ensures minimum damage and maximum quality.