Plaice are four species of flat fish in the family Pleuronectidae. The fish in this family are flounders, have both eyes on the right sides of their faces, and can have lifespans of more than two decades. Plaice are demersal fish, meaning they live at or near the bottom of the water. Two of the species are commercially fished, but there is disagreement about whether they are overfished.
The European plaice, Pleuronectes platessa, is commercially and recreationally fished in Europe. It is found off the coasts from the Barents Sea to the Mediterranean, the North Atlantic, and Greenland. The fish lives in the muddy bottoms, where it burrows into sediment during the day, and is found at depths of 32 to 164 feet (10 to 50 m). This species is dark green to dark brown with orange spots and a white underside, growing to up to 3 feet (1 m) in length and 15.5 pounds (7 kg) in weight.
Spawning occurs in late winter and early spring. The female sheds up to 500,000 eggs that are floating when fertilized. The young fish travels to the bottom of the water when it is 45 to 50 days old and reaches maturity at five to seven years. The diet consists of crustaceans, bivalves, and small fish.
The American plaice, Hippoglossoides platessoides, is also known as a sole. The fish is found in the Atlantic from southern Labrador to Rhode Island, spawning in April and May. The fish’s maximum length is 28 inches (70 cm). The fish are a brown to red color with larger scales than the European species. The American plaice is found at depths of 295 to 590 feet (90 to 180 m).
Commercially fished, the American plaice is considered overfished by the Northwest Atlantic Fisheries Organization. The Canadian government, however, states that the population of sole is abundant. There is some concern that even those species that aren’t commercially fished might be at risk because of being taken in by catch.
The Alaska plaice, Pleuronectes quadrituberculatus, is not generally commercially fished. These fish grow to lengths of 24 inches (60 cm) and are found in the northern Pacific Ocean from the Gulf of Alaska to the Chukchi Sea to the Sea of Japan. The scale-eye plaice, Acanthopsetaa nadeshnyi, can grow to 18 inches (46 cm) in length. It is found in the northern Pacific in the Sea of Okhotsk and the Bering Sea.