Haddock - Melanogrammus  aeglefinus               

Diagnostic features
Palatine teeth lacking. Chin barbel rather small. Lower jaw shorter than upper.  Three dorsal fins, two anal fins, all separate from each other; first anal fin base short, less than one-half of preanal distance.  Lateral line dark, uninterrupted to the end of body, or nearly so. Lateral-line pores present on head. Scales overlapping.  Colour: large dark blotch above pectoral fin.

Geographical distribution
In the eastern North Atlantic from the Bay of Biscay to Spitzbergen; in the Barents Sea to Novaya Zemlya; around Iceland; rare at the southern Greenland. In the western North Atlantic from Cape May, New Jersey to the Strait of Belle Isle.


Haddock - Geographical distribution


Habitat and biology
A demersal species found from 10 to 450 m depth, more common from 80 to 200 m,  over rock, sand, gravel or shells, usually at temperatures 2 between 4° and 10°C.  Haddock undertake extensive migrations in the Barents Sea and Iceland, and more restricted movements in the northwestern Atlantic, mostly to and 2 from the spawning grounds. First maturity is reached at 4 years for males and 5 years for females, except in the North Sea stock where it is reached at 2 and 3 years respectively. Although the overall sex ratio is about 1:1, females predominate in shallow waters and males on offshore grounds.

Fecundity ranges from 55 000 eggs for a 25 cm fish to 1 841 000 eggs for a 91 cm specimen. Spawning occurs in typically marine waters (35% salinity) between ca. 50 to 150 m depth, in the northwestern Atlantic from January to July (depending on the areas) and in the northeastern Atlantic from February to June (mostly in March-April). The eggs are pelagic and the larvae are believed to be pelagic for some 3 months.   Life expectancy is about 14 years.

The haddock is an omnivorous fish, feeding mainly on relatively small bottom-living organisms including crustaceans, molluscs, echinoderms, worms and fishes. 

Size
Rarely exceeding 1 m total length.

Fisheries
An important target species in North Atlantic fisheries. The major fishing grounds are located off the European coasts of Russia, around Iceland, in the Barents Sea, around the Faroe Islands, off western Norway and western Scotland, in the Celtic Sea, off Ireland, in the North Sea and in the English Channel. The haddock is fished with bottom trawls, longlines, gillnets and traps. It is marketed fresh, chilled as fillets, frozen, smoked and canned; also processed to fish-meal and used for animal feeds.