Petrale sole is a right-eyed flounder found along muddy bottoms off the Pacific coast. They range from Baja California up to Alaska and can be found at depths as far down as 1,370 feet, but are most commonly found between 330 and 500 feet deep.
Petrale sole have an oval to round body that is light to dark brown on its eyed side (top) with a white blind side (bottom) that occasionally has pink traces. Two rows of arrow shaped teeth occupy the top of their large mouth with one set of teeth on the lower jaw. They have a wonderfully sweet, delicate nutty flavor and thin fillets that are best cooked by simply sautéing.
From British Columbia to Oregon, Petrale sole spawn from November to April. The Californian-born fish begins spawning slightly earlier in the year. A large female can produce anywhere between 400,000 and 1.5 million eggs each about 0.05 inches in diameter. Since Petrale sole are broadcast spawners, the male and female release egg and sperm into the water column where they are then fertilized externally with the eggs hatching within six to 13 days. The hatched larvae grow in the pelagic water column for five to six months before they make the transformation to their adult form and settle on the bottom of the ocean floor. Young Petrale sole prey on mysids ,sculpins and other juvenile flat fish. Adults feed on shrimp, krill, pelagic fish and brittle stars. Petrale sole can reach sizes of up to two feet and are not sexually mature until between the ages of three and eight years. They can live up to 35 years.
This fishery uses a large cone-shaped net that is dragged along the seafloor to catch fish. As the net is towed at low speed, hydrodynamic forces push two "otter boards" outwards opening the mouth of the net and capturing fish in its path.