The Canadian plaice, also known as American plaice, is a flatfish commonly found in the cold waters of the North Atlantic. In Quebec, it is mainly present in the Gulf of St. Lawrence. Although it is less sought after for sport fishing due to its relatively non-combative behavior, it still attracts the interest of amateur fishermen for its delicious flesh and abundant presence. This benthic fish is often captured by commercial fishermen, but it also appeals to recreational anglers who appreciate the subtle challenges it presents. Its distribution ranges from shallow coastal waters to deeper seabeds, offering a variety of fishing habitats.

The Canadian plaice has a laterally flattened body, typical of fish in the Pleuronectidae family. Its color varies from reddish-brown to olive-brown, with irregular spots that allow it to effectively camouflage itself on sandy or muddy bottoms. Its upper side is pigmented, while the underside, which rests on the bottom, is usually white. The mouth of the plaice is slightly asymmetrical, with a lower jaw longer than the upper one. Its pectoral fins are small, and its dorsal fin extends almost from head to tail, which is rounded. The scales are small and well-anchored, providing a rough texture. Young plaices are often lighter than adults and may have more pronounced patterns. During spawning, females are generally more robust than males as they carry the eggs.

In Quebec, the Canadian plaice is mainly found in the Gulf of St. Lawrence and its surroundings. It is particularly abundant in the cold, salty waters of this region, where it benefits from sandy and muddy bottoms to feed and reproduce. Its presence is less frequent in warmer or fresher areas, as it prefers cooler temperatures. It is also absent from the inland waters of Quebec, being strictly marine. Overall, its distribution extends along the Atlantic coast, from Hudson Bay down to southern New England.

The Canadian plaice prefers shallow coastal waters but can be found at depths of up to 200 meters. It primarily inhabits sandy, muddy, or slightly gravelly bottoms, where it can effectively camouflage itself to avoid predators. The ideal temperatures for plaice range between 1 and 10 °C, which explains its presence in the colder waters of the Gulf of St. Lawrence. It is often observed near underwater structures such as reefs or wrecks, which provide both shelter and a plentiful food source. During the warm season, it may be found in slightly deeper waters in search of cooler temperatures.

The Canadian plaice spawns in the spring when temperatures begin to warm slightly. Females lay thousands of eggs, which float in the water column until they hatch. The eggs hatch into planktonic larvae that drift with the currents before metamorphosing into small flatfish and settling on the seabed. The growth of young plaices is relatively slow, reaching sexual maturity between 3 and 5 years. Adults can live up to 30 years, although most live between 20 and 25 years. Spring: Spawning and laying → Summer: Growth of young → Autumn: Maturity → Winter: Benthic life.

The Canadian plaice is primarily a solitary fish, although it may be seen in small groups when conditions are favorable, particularly during the spawning period. It is not particularly territorial, but it uses its natural camouflage to protect itself from predators. It reacts little to changes in light, preferring to remain buried in sand or mud during the day, becoming more active at dusk and dawn. Weather changes, such as wind or atmospheric pressure, have a moderate impact on its behavior, although it is more sensitive to underwater noise and vibrations.

The Canadian plaice is an opportunistic predator that primarily feeds on small benthic invertebrates. Young plaices mainly feed on zooplankton and small crustaceans. As they grow, their diet expands to include worms, mollusks, and small fish. During the summer, when food is abundant, it may feed more actively, while in winter, it tends to reduce its feeding activity due to colder temperatures and reduced prey availability.

In spring, the Canadian plaice is more active due to the spawning period, making it easier to catch. Fishermen can find it in shallower waters at this time. In summer, it moves to slightly deeper waters to avoid the heat, but remains active at dawn and dusk. Autumn is a transitional period where it prepares for winter, gradually reducing its activity. In winter, it is found in deeper waters and becomes less active, making it more difficult to catch. Weather conditions, such as overcast skies or light rain, may enhance its activity, while strong winds and very sunny days make it more discreet.

For fishing in clear waters, opt for lures in natural colors like brown or olive green that closely mimic the plaice's usual prey. In murky waters, brighter colors like yellow or red may be more effective in attracting attention. When the sun is out, metallic or reflective lures can simulate the reflections of fish scales, while in overcast weather, soft lures in opaque colors should be favored. In depth, use phosphorescent lures to maximize visibility.

A fishing rod of 1.8 to 2.4 meters with light to medium power and moderate action is recommended for targeting the Canadian plaice. An open-faced reel sized 2000 to 3000, spooled with braided line of 10 to 15 lb, offers good sensitivity and strength. Use hooks sized 2 to 4, suitable for natural or artificial baits. A fluorocarbon leader of 8 to 12 lb is ideal for discretion and abrasion resistance on rough bottoms.

When you catch a Canadian plaice, handle it carefully to avoid damaging it. Use a damp cloth to grasp it and avoid touching its gills. For a successful release, ensure it is well oxygenated before letting it go. If you wish to take a photo, do so quickly to minimize stress. Make sure the plaice is fully submerged before letting it swim away.

The aquatic predators of the Canadian plaice mainly include large fish such as striped bass and halibut. Seals and seabirds, such as gulls, may also prey on young plaices or weakened adults. These interactions are part of the complex marine ecosystem where the plaice plays a crucial role.

The Canadian plaice is not currently considered a threatened species in Quebec, but it is subject to fishing regulations aimed at maintaining sustainable populations. Catch quotas and fishing seasons are regulated to prevent overfishing. The release of unwanted or undersized specimens is encouraged to contribute to the conservation of the species.