The haddock, also known as "églefin," is a sea fish appreciated for its delicate flesh and commercial importance. In Quebec, haddock is not a primary target for sport fishing, but it is sometimes caught by amateur anglers seeking other species in the salty and brackish waters of the Gulf of St. Lawrence. Although it is not known for its intense fight, it still offers an interesting catch for those looking to diversify their catches. Its distribution is mainly concentrated in the cold waters of the North Atlantic, and it is often fished commercially rather than sportingly.

The haddock is easily recognizable by its slender body and grayish to brownish coloration on the back, which fades to become paler on the sides and belly. One of the most distinctive features of the haddock is the black spot located just above the pectoral fin, often called the "devil's mark." Its dorsal fins are three in number, with the first being the longest. The haddock's mouth is relatively small, slightly inferior, with a shorter lower jaw than the upper. The scales are small and smooth, giving the skin a slightly satin-like appearance. Young haddocks resemble adults but are generally paler and less marked, while males and females are difficult to distinguish visually, even during spawning season.

Haddock is primarily found in the cold waters of the North Atlantic and is present in the Gulf of St. Lawrence in Quebec. It is often encountered in coastal waters, although it can live at depths of up to 300 meters. Its presence is more marked off the coast of Gaspésie and around the Îles-de-la-Madeleine. The species is generally abundant in these regions, but it is less common in inland waters. Its distribution is influenced by ocean currents and spawning areas.

Haddock prefers cold and brackish waters, often near sandy or muddy seabeds. It is common to find it in bays, estuaries, and continental shelves, where it can feed efficiently. Adults generally stay at depths between 40 and 150 meters, although they can descend to 300 meters. Young haddocks tend to remain in shallower waters. The ideal temperature for haddock ranges from 2 to 10 °C, and it is often associated with nutrient-rich waters, promoting prey proliferation.

Haddock reproduction usually takes place in the spring when adults migrate to shallow spawning areas. Females lay several thousand floating eggs that drift in ocean currents. After hatching, the larvae feed on zooplankton before moving to the bottom as they grow. Growth is relatively fast during the first years, and haddocks reach sexual maturity at about 3 to 4 years of age. The species' lifespan can reach 14 years, although most individuals live between 7 and 10 years.

Spring → Migration and spawning → Summer → Juvenile growth → Autumn → Dispersion to deeper waters → Winter → Resting period.

Haddock is a gregarious fish, often found in schools that move together for feeding and protection from predators. It is not particularly territorial and tends to avoid areas of strong turbulence or excessive noise. Haddocks are more active during periods of low light, preferring cloudy days or twilight for feeding. They are sensitive to pressure changes and can adjust their depth in response to weather conditions.

The haddock's diet varies with age. The young feed mainly on zooplankton and small crustaceans. As they grow, their diet expands to include mollusks, marine worms, and small fish. Adults are opportunistic predators that hunt a variety of benthic prey, such as shrimp and crabs. Their feeding habits also change with the seasons, with increased activity in spring and summer when food resources are more abundant.

In spring, haddock moves closer to the coast to spawn, making it a prime time to fish in shallow waters. In summer, it disperses to deeper areas where temperatures remain cool. Autumn is a transition period, with movements to more stable winter habitats. During winter, feeding activity decreases, and haddock stays in deeper waters, making fishing more challenging. The best times to fish for haddock are early morning or late afternoon, especially in overcast or slightly rainy weather, when atmospheric pressure is stable.

For haddock fishing, choose lures in natural colors that mimic local prey. In clear water, silver and blue colors are effective, while in murky water, opt for more contrasting shades like yellow or orange. On sunny days, metallic lures that reflect light well are preferable. On cloudy days, dark-colored lures or those with contrasting patterns may better attract attention.

For haddock fishing, use a 2.1 to 2.4-meter fishing rod with moderate action, capable of handling medium lures. A medium-sized spinning reel, filled with 10 to 15 lb line, is ideal. Circle hooks size 1/0 to 2/0 are recommended to minimize injury. A 20 lb fluorocarbon leader can be used to avoid abrasion against the seabed.

Handle haddock carefully by supporting it by the belly to avoid damaging its internal organs. If you wish to release it, do so quickly to minimize stress. Ensure the haddock is well-oxygenated before release. For a photo, hold it horizontally to avoid causing injuries.

The main predators of haddock in Quebec include seals, sharks, and large predatory fish like halibut. Seabirds, such as gulls, can also capture young haddocks near the surface.

Haddock is a commercially important species, but its population is subject to fluctuations due to intensive fishing. In Quebec, haddock management includes catch quotas to ensure stock sustainability. It is important to respect local regulations and encourage the release of unwanted catches to help conserve this species.