The white lussion (Arctozenus risso) is a little-known fish among sport fishermen in Quebec due to its small size and deep marine habitat. However, it plays an important role in the marine ecosystem as prey for many predators. Its distribution is primarily oceanic, found in the cold, deep waters of the North Atlantic, including the Gulf of St. Lawrence. Although it is not targeted for sport fishing, its presence is crucial for the health of predator fish populations like halibut and tuna that inhabit these same waters.

The white lussion has an elongated and slender body, typical of fish in the Paralepididae family. Its color is generally silvery, allowing it to effectively camouflage in deep waters. Its scales are small and smooth, and it has a relatively large mouth filled with sharp teeth, adapted for capturing small prey. The fins are quite reduced, with a dorsal fin located towards the center of the body and a forked caudal fin. Young fish resemble adults but are often more translucent. There is no notable difference between males and females, even during spawning.

In Quebec, the white lussion is mainly present in the deep waters of the Gulf of St. Lawrence and the estuary. It prefers marine areas with cold temperatures, often beyond 100 meters in depth. It is less abundant near the coast, where conditions are not ideal for its lifestyle. Its distribution is largely influenced by the availability of its prey and the ocean currents that bring nutrients. Although it is present in these regions, it is rarely observed due to its habitat being far from the shore.

The white lussion primarily frequents deep oceanic areas, where the water temperature is cold, generally between 2 and 10 °C. It is often found at depths exceeding 100 meters, where it can hide from larger predators. Underwater structures such as canyons and submarine plateaus are typical places where it can be found, as they provide an abundance of food. Clear water is often preferred, but it can also be found in slightly brackish waters near river mouths.

The life cycle of the white lussion begins with egg spawning in the open sea, usually in late spring or early summer. The eggs float in the water column until hatching, releasing fry that will feed on zooplankton. As they grow, they descend to deeper waters where they continue to develop. Sexual maturity is reached relatively early, around 1 to 2 years of age, which is typical for species living in environments with high predation. The average lifespan is 5 to 7 years. Spring: Spawning → Summer: Growth of juveniles → Autumn: Descent to depths → Winter: Life in deep waters.

The white lussion is a schooling fish, often found in small schools, which helps protect against predators. It is not particularly territorial, preferring to follow currents and the movements of its prey. Sensitive to changes in pressure, it may react to disturbances such as storms or boat movements, although it is generally too deep to be affected by surface noise. Light plays a minimal role in its daily behavior, as it primarily lives in the darkness of the depths.

The diet of the white lussion varies according to its stage of development. Fry primarily feed on zooplankton, while adults consume small fish and crustaceans. Prey often includes species of krill and small fish like sand lance. In winter, when food resources are more limited, they may migrate to areas where food is more abundant. They primarily hunt at dawn and dusk, using their speed and agility to capture their prey.

Fishing for the white lussion is not a common activity in Quebec due to its deep habitat. However, for scientific observation, it is noted that spring is the spawning season, and populations may be more concentrated at that time. In summer, they descend deeper as surface temperatures rise. Autumn and winter see the white lussion remaining in depth, where the waters are more stable. Weather conditions have little direct impact on this species due to its depth of life, although storms may affect the distribution of its prey.

Since the white lussion is not a target for sport fishing, there are no specific lures used for its capture. However, for scientific studies, the nets used are often neutral in color to minimize disruption of their natural behavior. In the rare cases where a lussion might be accidentally caught, it would likely be attracted by baits mimicking small fish or crustaceans, suited to its diet.

For the white lussion, sport fishing gear is generally not relevant. However, for scientific studies, trawl nets suited for depth, as well as weighted lines, are used. The gear must be robust to withstand the pressure of deep waters. Hooks are not used directly for this species, as it is not targeted by recreational fishing.

Handling the white lussion, when captured for studies, must be done carefully to avoid damaging the specimens. Release must be quick to minimize stress. For photos, it is important to keep the fish moist and limit the time out of the water.

The main predators of the white lussion include halibut, tuna, and sharks, which share its deep habitat. Seabirds, such as gannets, are generally not predators due to the depth at which the white lussion lives.

The white lussion is not subject to targeted commercial or recreational fishing in Quebec. Its conservation status is not concerning, but it is important as a prey species in the marine ecosystem. Regulations focus on protecting deep marine habitats rather than the species itself.