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Amendment 80 Checklist
Small Entity Compliance Guide for the Amendment 80 Groundfish Trawl Fisheries.
Rock Sole
Rock Sole
Lepidopsetta billineta (southern rock sole) and Lepidopsetta polyxystra (northern rock sole)
Also Known As
Sole, Flounder, Rock flounder, Two-lined flounder, White-bellied flounder
Quick Facts
Region
Alaska,
West Coast
About the Species
U.S. wild-caught rock sole is a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations.
Population
Above target population levels in Alaska.
Fishing Rate
At recommended levels.
Habitat Impacts
Area closures and gear restrictions protect habitat affected by bottom trawls used to harvest rock sole.
Bycatch
Regulations are in place to minimize bycatch.
Population Status
- There are two species of rock sole, northern rock sole and rock sole.
- In the Bering Sea/Aleutian Islands, northern rock sole is assessed and is the primary species that is part of a complex with rock sole, called the “rock sole complex”:
- According to the 2017 stock assessment, this complex is not overfished and not subject to overfishing.
- In the Gulf of Alaska, northern rock sole and rock sole are assessed and are the primary species that are part of a complex, called the “shallow water flatfish complex":
- According to the 2018 stock assessment, this complex is not overfished and not subject to overfishing.
- On the West Coast, rock sole make up only a small percentage of groundfish harvests. Scientists do not formally assess this species so the population status is unknown.
- Rock sole are part of the “other flatfish” complex on the West Coast, and are not subject to overfishing based on 2018 catch data.
Appearance
- Rock sole are a flatfish with both eyes located on the right side of their head.
- Northern rock sole’s underside is creamy white, whereas southern rock sole’s underside is white with glossy highlights.
- Rock sole are sometimes called roughback because of the rough scales on their backs.
Biology
- Rock sole grow up to 2 feet long and can live for more than 20 years.
- They are able to reproduce when they reach 4 to 7 years old.
- Northern rock sole spawn in midwinter and spring, and southern rock sole spawn in the summer.
- Females lay eggs near the ocean bottom, and the eggs stick wherever they land. Eggs hatch between 6 and 25 days later, depending on water temperature.
- Larval rock sole eat plankton and algae.
- Early juveniles eat zooplankton, and late juvenile and adults prey on bivalves, worms, amphipods, mollusks, and crustaceans.
- Larger fishes, including rock sole, feed on larval and juvenile rock sole.
- Sharks, marine mammals, and larger fishes prey on adults.
- Rock sole’s coloring and movements on the sea floor often confuse predators.
Where They Live
- Northern rock sole are found from Puget Sound through the Bering Sea and Aleutian Islands to the Kuril Islands (north of Japan).
- Southern rock sole are found from the southeast Bering Sea to Baja California.
Fishery Management
- NOAA Fisheries and the North Pacific Fishery Management Council manage this fishery in Alaska.
- Managed under the Fishery Management Plans for Groundfish of the Bering Sea and Aleutian Islands and Gulf of Alaska:
- Fishermen must have a permit to participate in the fishery, and the number of available permits is limited to control the amount of fishing.
- Managers set an annual catch limit for rock sole.
- In the Bering Sea/Aleutian Islands a percentage of the annual catch limit is allocated to the community development quota program, which benefits fishery-dependent communities in Western Alaska. The rest is allocated under a catch share program to a trawl catcher/processor sector based on historic harvest and future harvest needs to improve retention and utilization of fishery resources by the trawl fleet.
- In the Gulf of Alaska, total allowable catch is allocated by regulatory area (western, central, and two sub-areas of the eastern Gulf of Alaska).
- Catch is monitored through record keeping, reporting requirements, and observer monitoring.
- NOAA Fisheries and the Pacific Fishery Management Council manage this fishery on the West Coast.
- Managed under the Pacific Coast Groundfish Fishery Management Plan:
- Only a small amount of rock sole is harvested incidentally in fisheries off the West Coast.
- Rock sole is included in the groundfish fishery management plan, but it is not assessed or directly managed.
Harvest
- In 2018, commercial landings of rock sole totaled more than 64.2 million pounds and were valued at more than $14.8 million.
- Almost all commercial harvest of rock sole comes from Alaska, mainly the Bering Sea.
- Gear types, habitat impacts, and bycatch:
- Bottom trawls are primarily used to harvest rock sole.
- Trawls can contact the ocean floor and impact habitats, depending on the characteristics of the ocean bottom and the size of the gear.
- Bering Sea/Aleutian Islands and Gulf of Alaska fishermen use a modified trawl gear which reduces the impact of trawling on animals living on the sea floor, including crabs.
- Halibut, salmon, and crab are sometimes incidentally caught in the groundfish fishery in Alaska.
- There is a limit on how much halibut, herring, and crab can be incidentally caught. If this limit is reached, an area or the entire fishery is closed for the remainder of the season.
- NOAA Fisheries and the regional fishery management council have implemented large closed areas to protect sensitive rocky, cold-water coral and sponge habitats from bottom trawls.
Featured News
Science Overview
NOAA Fisheries conducts various research activities on the biology, behavior, and ecology of rock sole. The results of this research are used to inform management decisions for this species.
Rock Sole in Alaska
Our research in Alaska on the distribution and abundance, growth and maturity, habitat preference, migration behavior, and food relationships of rock sole provides information crucial for understanding and managing this species.