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Haddock

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The haddock, known scientifically as Melanogrammus aeglefinus, is a saltwater fish. It belongs to the family Gadidae, which contains the true cods. This fish is unique because it is the only species in its genus, Melanogrammus.

Melanogrammus aeglefinus
Melanogrammus aeglefinus

Haddock are vital to global fisheries, particularly in northern Europe. In these regions, they are sold fresh, frozen, or smoked. Some famous smoked varieties include the Finnan haddie and the Arbroath smokie. Other styles include long boneless fillets, which are smoked using oak chips with the skin left on.

10th May 2012 Smoked Haddock
10th May 2012 Smoked Haddock

Physically, the haddock has an elongated, tapering body shape. This shape is very common among members of the cod family. Its mouth is relatively small and does not reach below the eye. The face has a straight lower profile and a slightly rounded upper profile. This creates a snout that looks like a wedge. The upper jaw projects further than the lower jaw, even more so than in the Atlantic cod. A small barbel, which is a fleshy whisker, sits on its chin.

Haddock fins
Haddock fins

The haddock possesses several specific fins that help it move. It has three dorsal fins on its back. The first is triangular and contains 14 to 17 fin rays. The second has 20 to 24 rays, and the third has 19 to 22 rays. There are also two anal fins on the underside. The first anal fin has 21 to 25 rays, while the second has 20 to 24 rays. All these fins are separated from one another. The pelvic fins are small and feature an elongated first fin ray.

Coloration is a key way to identify a haddock. The upper body ranges from dark grey-brown to nearly black. The lower body is a dull silvery white. A distinctive black lateral line curves over the pectoral fins. A very famous feature is an oval black blotch called a "thumbprint." Some people call this the "Devil's thumbprint." This mark sits between the lateral line and the pectoral fin. The genus name Melanogrammus comes from the Greek words "melanos," meaning black, and "gramma," meaning letter or signal.

Haddock are demersal, meaning they live near the ocean floor. They typically live at depths between 20 and 200 meters. They are most often found at 50 to 150 meters. These fish prefer substrates like rock, sand, gravel, or shells. They thrive in water temperatures between 2 and 11 degrees Celsius.

Melanogrammus aeglefinus
Melanogrammus aeglefinus

In the North Atlantic, they have populations on both sides of the ocean. They are more abundant in the eastern Atlantic. Large stocks exist in the North Sea, near the Faroe Islands, Iceland, and Norway. In North America, they live from western Greenland down to Cape Hatteras.

The life cycle of a haddock involves many stages. They reach sexual maturity at 4 years for males and 5 years for females. However, the North Sea population matures faster, at 2 years for males and 3 years for females. Females produce many eggs, a measure called fecundity. A fish of 50 centimeters long may bear 55,000 eggs. A much larger fish of 100 centimeters can produce 1,841,000 eggs. The eggs are pelagic, meaning they float in the open water. They have a diameter of 1.2 millimeters and hatch in one to three weeks. Once they undergo metamorphosis, the larvae remain pelagic until they reach 10 centimeters. At that point, they settle into a demersal habit on the bottom.

Dietary habits change as the fish grows. Larval haddock eat tiny creatures like copepods and ostracods. As they grow, they eat larger prey like amphipods and even invertebrate eggs. Once they become demersal, they switch to benthic prey. This includes bottom-dwelling animals like sea urchins, brittlestars, bivalves, and worms. They also eat smaller fish like capelin or sandeels. Haddock are part of a complex food web. Juvenile haddock are eaten by larger fish, while seals prey on the larger adults.

Haddock landings east
Haddock landings east

Humans have fished haddock for a very long time. Carolus Linnaeus first described the species in 1758. In 1862, Theodore Nicholas Gill created the genus Melanogrammus. Today, haddock is a major commercial resource. In the eastern Atlantic, landings reached between 200,000 and 350,000 tonnes between 1980 and 2017.

Haddock landings east
Haddock landings east

In North America, the catch was 40,000 to 60,000 tonnes annually between 1920 and 1960. It declined sharply in the late 1960s. Scientists now manage these stocks carefully to ensure they remain sustainable. Many fisheries are even certified by the Marine Stewardship Council.

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🖼️ Images & Media (4)
File:Melanogrammus aeglefinus.png
Melanogrammus aeglefinus.png
Haddock fins.tiff
File:Haddock landings east.jpg
Haddock landings east.jpg
File:10th May 2012 Smoked Haddock.jpg
10th May 2012 Smoked Haddock.jpg
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