The haddock ( Melanogrammus aeglefinus) is a saltwater ray-finned fish from the family Gadidae, the true cods. It is the only species in the Monotypy genus Melanogrammus. It is found in the North Atlantic Ocean and associated seas, where it is an important species for fisheries, especially in northern Europe, where it is marketed fresh, frozen and Smoked fish; smoked varieties include the Finnan haddie and the Arbroath smokie. Other smoked versions include long boneless, the filleted side of larger haddock smoked in oak chips with the skin left on the fillet.
The upper side of the haddock's body varies in colour from dark grey brown to nearly black while the lower part of the body is dull silvery white. It has a distinctive black lateral line contrasting with the whitish background colour and which curves slightly over the . It also has a distinctive oval black blotch or 'thumbprint', sometimes called the "Devil's thumbprint", which sits between the lateral line and the pectoral fin, a feature which leads to the name of the genus Melanogrammus which derives from Greek language "melanos" meaning "black" and "gramma" meaning letter or signal. The dorsal, pectoral, and are dark grey in colour while the anal fins are pale matching the colour of the silvery sides, with black speckles at their bases. The pelvic fins are white with a variable amount of black spots. Occasionally there are differently coloured variants recorded which may be barred, golden on the back or lack the dark shoulder blotch.
The longest haddock recorded was in length and weighed . However, haddock are rarely over in length and the vast majority of haddocks caught in the United Kingdom measure between . In eastern Canada waters, haddock range in size from in length and in weight.
The fecundity of the females varies with size: a fish of length bears 55,000 eggs while a fish at has 1,841,000 eggs. Spawning takes place from depths of around . In the northwestern Atlantic spawning lasts from January to July, although it does not occur simultaneously in all areas, and in the northeastern Atlantic the spawning season runs from February to June, peaking in March and April. The eggs are pelagic with a diameter of , and they take one to three weeks to hatch. Following metamorphosis, the past larval fish remain pelagic until they attain a length of around , when they settle to a demersal habit. Their growth rate shows considerable regional variation and fish at one year old can measure , at 2 years old , up to at 13 years old. Their lifespan is around 14 years. The most important spawning grounds are in the waters off the central coast of Norway, off the southwest of Iceland, and over the Georges Bank. The fish which spawn in inshore waters are normally smaller and younger fish than those which occur in offshore areas. The younger fish have a spawning season which is less than half of that of the larger and older stock offshore. Once hatched the larvae do not appear to travel far from their spawning grounds, however some larvae spawning off the west coast of Scotland are transported into the North Sea through the Fair Isle-Shetland Gap or to the northeast of Shetland.
In their larval stages, haddock mainly feed on the immature stages of , Ostracod and limacina with their diet changing as they grow, moving on to larger pelagic prey such as Amphipoda, Krill, eggs of invertebrates, zoea larvae of Decapoda and increasing numbers of copepods. Once they have reached the settled, demersal, post-larval stage, they gradually switch from pelagic to benthic prey. Adults primarily feed on benthic invertebrates such as sea urchins, Brittle star, Bivalvia and worms, however, they will feed opportunistically on smaller fish such as capelin, Sand eel and Norway pout. Juvenile haddock are an important prey for larger demersal fish, including other Gadiformes, while seals prey on the larger fish.
The recorded growth rates of haddock underwent significant change over the 30 to 40 years up to 2011. Growth has been more rapid in recent years, with haddock attaining adult size much earlier than was noted 30–40 years ago. However, the degree to which these larger, younger fish contribute to reproductive success of the population is unknown. The growth rates of haddock, however, have slowed in recent years. There is some evidence which indicates that these slower growth rates may be the result of an exceptionally large year class in 2003. The haddock stock periodically has higher than normal productivity; for example in 1962 and 1967, and to a lesser extent, 1974 and 1999. These result in a more southerly distribution of the fish and have a strong effect on the biomass of the spawning stock, but because of high fishing mortality, these revivals do not have any lasting effect on the population. In general, there was above average recruitment from the 1960s up to the early 1980s, similar to recruitment for Atlantic cod and whiting, this has been called the gadoid outburst. There was strong recruitment in 1999 but since then, the recruitment rate has been very low.
The female worm, with her now fertilized eggs, then finds a cod, or a cod-like fish such as a haddock or whiting. There, the worm clings to the while it metamorphoses into a plump, sinusoidal, wormlike body, with a coiled mass of egg strings at the rear. The front part of the worm's body penetrates the body of the cod until it enters the rear bulb of the host's heart. There, firmly rooted in the cod's circulatory system, the front part of the parasite develops like the branches of a tree, reaching into the main artery. In this way, the worm extracts nutrients from the cod's blood, remaining safely tucked beneath the cod's gill cover until it releases a new generation of offspring into the water.
The generic name Melanogrammus means "black line", a reference to the black lateral line of this species. The specific name is a latinisation of the vernacular names egrefin and eglefin, used in France and England.
Haddock currently resides on the Greenpeace seafood red list due to concerns regarding the impact of bottom trawls on the marine environment. In contrast, Monterey Bay Aquarium considers haddock a "good alternative". Many haddock fisheries have been certified as sustainable by the Marine Stewardship Council. All seven stocks assessed in the eastern Atlantic are currently considered by ICES to be harvested sustainably. The haddock populations in the western Atlantic (offshore grounds of Georges Bank off New England and Nova Scotia) are also considered to be harvested sustainably.
The smoking of haddock was highly refined in Grimsby. Traditional Grimsby smoked fish (mainly haddock, but sometimes cod) is produced in the traditional smokehouses in Grimsby, which are mostly family-run businesses that have developed their skills over many generations. Grimsby Traditional Fish Smokers Group Grimsby fish market sources its haddock from the North East Atlantic, principally Iceland, Norway and the Faroe Islands. These fishing grounds are sustainably managed Icelandic Request on the Evaluation of Icelandic Cod and Haddock Management Plan and have not seen the large scale depreciation in fish stocks seen in EU waters. European Commission, Communication on Fishing Opportunities for 2009. May 2008
One popular form of haddock is Finnan haddie which is named after the fishing village of Finnan or Findon in Scotland, where the fish was originally cold-smoked over smouldering peat. Finnan haddie is often poached in milk and served for breakfast. Full recipe for Finnan Haddie from Scottish chef John Quigley
The town of Arbroath on the east coast of Scotland produces the Arbroath smokie. This is a hot-smoked haddock which requires no further cooking before eating.
Smoked haddock is naturally an off-white colour and it is frequently yellow, as are other smoked fish. Smoked haddock is the essential ingredient in the Anglo-Indian dish kedgeree, and also in the Scottish dish Cullen skink, a chowder-like soup.
Distribution
Habitat and biology
Parasites
Taxonomy and etymology
Fisheries
As food
Further reading
External links
|
|