Northern rock sole facts for kids

The northern rock sole (Lepidopsetta polyxystra) is a type of flatfish. It belongs to the flounder family. This fish lives near the bottom of the ocean. It prefers sand, mud, and gravel. You can find it in waters up to 700 meters (2,300 feet) deep. However, it is most common between 19 and 246 meters (62 and 807 feet) deep.

This fish lives in the cool waters of the northern Pacific Ocean. Its home ranges from Puget Sound to Alaska. It also lives around the Aleutian Islands. You can find it across the Bering Sea to the Kuril Islands and the Sea of Okhotsk. Male northern rock soles can grow up to 69 cm (27 in) long. Females can reach 49 cm (19 in). The longest a northern rock sole has lived is 18 years.

How Scientists Name and Group Fish

Before the year 2000, the northern rock sole and the rock sole were thought to be the same fish. They were both called Lepidopsetta bilineata. But in 2000, scientists Orr and Matarese studied them closely. They found that these fish were actually different.

So, they changed how the fish in the Lepidopsetta group were classified. They created three separate types. Because of this change, the original rock sole is sometimes called the "southern" rock sole. This helps avoid confusion with the northern rock sole (L. polyxystra).

Northern Rock Sole in the Food Chain

The northern rock sole has an important role in the ocean's food chain. It is a moderately high-level consumer. This means it eats other creatures and is also eaten by larger animals.

What Northern Rock Sole Eat

Northern rock soles mostly eat small creatures that live on the seafloor. Their diet includes polychaete worms and amphipods. Amphipods are tiny shrimp-like animals.

Who Eats Northern Rock Sole

Many animals hunt and eat northern rock soles. These include marine mammals like seals. Other fish also prey on them. Some of these fish are sharks, Alaska pollock, yellowfin sole, Pacific halibut, and Pacific cod.

Reproduction and Life Cycle

Northern rock soles become old enough to reproduce between 4 and 7 years of age. They lay their eggs from winter to early spring. The eggs sink to the bottom and stick to surfaces. It takes about 6 to 25 days for the eggs to hatch.

Commercial Fishing of Northern Rock Sole

People catch northern rock sole for food. It is an important fish for two large trawl fisheries. These fisheries are in the Bering Sea and the Gulf of Alaska. In the 1960s, too many northern rock soles were caught. This is called overfishing.

However, the number of fish has grown back. Today, there are many northern rock soles in the Bering Sea and Aleutian Islands fishery. Their total weight is very high. It is twice the amount needed to catch fish sustainably. In 2008, the estimated weight of northern rock sole in the Gulf of Alaska fishery was about 102,303 tons. The amount caught ranged from 453 tons in 2004 to 4,330 tons in 2006.

Fishing for northern rock sole off the coast of the United States is managed. The North Pacific Fishery Management Council oversees this. It is one of eight councils that manage fisheries in the U.S.