The haddock is a marine fish distributed on both sides of the North Atlantic. Haddock
is a popular food fish and is widely fished commercially.
The haddock is easily recognized by a black lateral line running along its white side
and a distinctive dark blotch above the pectoral fin, often described as a "thumbprint" or
even the "Devil's thumbprint" or "St. Peter's mark".
Haddock is most commonly found at depths of 40 to 133 m, but has a range as deep as 300 m.
It thrives in temperatures of 2 to 10°C. Juveniles prefer shallower waters and larger
adults deeper water. Generally, adult haddock do not engage in long migratory behaviour
as do the younger fish, but seasonal movements have been known to occur across all ages.
Haddock feed primarily on small invertebrates, although larger members of the species may
occasionally consume fish. Growth rates of haddock have changed significantly
over the past 30 to 40 years. Presently, growth is more rapid, with haddock reaching their
adult size much earlier than previously noted. However, the degree to which these younger
fish contribute to reproductive success of the population is unknown. Growth rates of
haddock, however, had slowed in recent years. Some evidence indicates it may be the result
of an exceptionally large year class in 2003. Spawning occurs between January and June,
peaking during late March and early April. The most important spawning grounds are in
the waters off middle Norway, near southwest Iceland, and Georges Bank. An average-sized
female produces approximately 850,000 eggs, and larger females are capable of producing
up to 3 million eggs each year.
Parasites Cod and related species are plagued by parasites.
For example the cod worm, Lernaeocera branchialis, starts life as a copepod, a small, free-swimming
crustacean larva. The first host used by cod worm is a flatfish or lumpsucker, which they
capture with grasping hooks at the front of their bodies. They penetrate the lumpsucker
with a thin filament which they use to suck its blood. The nourished cod worms then mate
on the lumpsucker. 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 gills 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. Fisheries
Reaching sizes up to 1.1 m, haddock is fished for year-round. Some of the methods used are
Danish seine nets, trawlers, long lines and fishing nets. The commercial catch of haddock
in North America had declined sharply in recent years, but is now recovering, with recruitment
rates running around where they historically were from the 1930s to 1960s.
In 2010, Greenpeace International has added the haddock to its seafood red list. "The
Greenpeace International seafood red list is a list of fish that are commonly sold in
supermarkets around the world, and which have a very high risk of being sourced from unsustainable
fisheries." Haddock populations on the offshore grounds
of Georges Bank off New England and Nova Scotia have made a remarkable comeback with the adoption
of catch shares management program, and are currently harvested at only a fraction of
sustainable yields.
As food
Haddock is a very popular food fish, sold fresh, smoked, frozen, dried, or to a small
extent canned. Haddock, along with Atlantic cod and plaice, is one of the most popular
fish used in British fish and chips. Fresh haddock has a clean, white flesh and
can be cooked in the same ways as cod. Freshness of a haddock fillet can be determined by how
well it holds together, as a fresh one will be firm; also, fillets should be translucent,
while older fillets turn chalky. Young, fresh haddock and cod fillets are often sold as
scrod in Boston, Massachusetts; this refers to the size of the fish which have a variety
of sizes, i.e. scrod, markets, and cows. Haddock is the predominant fish of choice in Scotland
in a fish supper. It is also the main ingredient of Norwegian fishballs.
Unlike the related cod, haddock does not salt well and is often preserved by drying and
smoking. The smoking of haddock was highly refined
in Grimsby. Traditional Grimsby smoked fish is produced in the traditional smokehouses
in Grimsby, which are mostly family-run businesses that have developed their skills over many
generations. Grimsby fish market sources its haddock from the North East Atlantic, principally
Iceland, Norway and the Faroe Islands. These fishing grounds are sustainably managed and
have not seen the large scale depreciation in fish stocks seen in EU waters.
One popular form of haddock is Finnan haddie which takes its name from the fishing village
of Finnan or Findon in Scotland, where it was originally cold-smoked over peat. Finnan
haddie is often served poached in milk for breakfast.
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 naturally has an off-white colour; it is very often dyed 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".
Notes
Other references Sobel. Melanogrammus aeglefinus. 2006. IUCN
Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 11 May 2006.
Listed as Vulnerable "Melanogrammus aeglefinus". Integrated Taxonomic
Information System. Retrieved 24 January 2006. Froese, Rainer and Pauly, Daniel, eds.. "Melanogrammus
aeglefinus" in FishBase. May 2005 version. Alan Davidson, North Atlantic Seafood, 1979,
ISBN 0-670-51524-8. Haddock NOAA FishWatch. Retrieved 5 November
2012.