Melanogrammus aeglefinus Linnaeus, 1758, Oceano Europeo.
OTHER COMMON NAMES
Three separate dorsal fins, two separate anal fins. Dorsal and anal fins separated by narrow gaps. Small chin barbel present. Pelvic fins sometimes with one elongate ray. Lateral line dark. A prominent blotch on side over the pectoral fin.
Eastern North Atlantic from Bay of Biscay to Spitzbergen; Barents Sea; around Iceland and southern tip of Greenland; Western North Atlantic from Labrador to Cape Charles, Virginia. In the western Atlantic, highest abundance occurs over Georges Bank, Scotian Shelf, and southern Grand Bank. The highest concentrations off the United States are associated with the two major stocks located on Georges Bank and in the southwestern Gulf of Maine.
Haddock are most common at depths of 148–443 ft (45–135 m) and temperatures of 36–50°F (2.2–10°C). Substrates preferred include rock, sand, gravel, or broken shell. Gravelly sand and gravel are preferred in the Western Atlantic. Haddock exhibit age-dependent shifts in habitats use, with juveniles occupying shallower water on bank and shoal areas, and larger adults associated with deeper water.
Adult haddock do not undertake long migrations, but seasonal movements occur in the western Gulf of Maine, the Great South Channel, and on the northeast peak of Georges Bank.
FEEDING ECOLOGY AND DIET
Crustaceans, echinoderms, polychaetes, and mollusks are the most important prey items for juveniles and adults combined. Juveniles prey mostly on crustaceans. Other fishes are of minor importance in the haddock’s diet.
Spawning occurs between January and June, with peak activity during late March and early April. An average-sized 21.7 in (55 cm) female produces approximately 850,000 eggs, and larger females are capable of producing up to three million eggs annually. Spawning concentrations occur on eastern Georges Bank, to the east of Nantucket Shoals, and along the Maine coast. Growth and maturation rates of haddock have changed significantly over the past 30 to 40 years. During the early 1960s, all females age four and older were fully mature, and approximately 75% of age three females were mature. Presently, growth is more rapid, with haddock reaching 18.9 to 19.7 in (48 to 50 cm) at age three. Nearly all age three and 35% of age two females are mature. Although early maturing fish increase spawning stock biomass, the degree to which these younger fish contribute to reproductive success of the population is uncertain.
Listed as Critically Endangered by the IUCN. The spawning stock biomass of Georges Bank haddock declined from 76,000 tn (69,000 t) in 1978 to 12,125 tn (11,000 t) by 1993, and has since increased to 41,900 tn (38,000 t) in 1998. However, spawning stock biomass is presently below the minimum threshold level of 58,400 tn (53,000 t), indicating the stock is in an overfished condition. Observed increases in spawning stock biomass of Georges Bank haddock have resulted from conservation of existing year classes. This is a necessary first step in the stock rebuilding process. Recent research vessel surveys provide indications that the 1998 year class may be the strongest in two decades. If this recruitment is realized, there is a potential for significant stock rebuilding.
SIGNIFICANCE TO HUMANS
An extremely valuable fishery on both sides of the North Atlantic. In 1987, the FAO reported that landings of this species amounted to 439,295 tn (398,522 t), of which total most (400,530 tn; 363,353 t) was taken in the northeastern Atlantic. Leading fishing countries are United Kingdom, Russia, Norway, and Iceland, followed by France, Denmark, and others. Northwest Atlantic landings are dominated by Canada, followed by the United States.
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