Summer Flounder
Summer Flounder
Paralichthys dentatus
Quick Facts
Summer flounder. Credit: NOAA Fisheries
Summer flounder. Credit: NOAA Fisheries
About the Species
The summer flounder fishery in the U.S. operates from Maine to the North Carolina/South Carolina border. Summer flounder is one of the most sought after commercial and recreational fish along the Atlantic coast. Summer flounder is found in inshore and offshore waters from Nova Scotia, Canada, to the east coast of Florida. Summer flounder are mainly caught in bottom otter trawls, but are also taken by pound nets and gillnets in estuarine waters. The market for summer flounder is for human consumption and is primarily sold fresh. U.S. wild-caught summer flounder is a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations. Implementing regulations are found at 50 CFR part 648 subpart G.
Population
The stock is not overfished.
Fishing Rate
Reduced to end overfishing.
Habitat Impact
Bottom trawls can impact bottom habitats. However, summer flounder live on sandy ocean bottom habitat, which is more resilient than other habitat types to the impacts of fishing gear.
Bycatch
Regulations are in place to minimize bycatch.
Population Status
- According to the 2023 stock assessment, summer flounder is not overfished, but is subject to overfishing. Summary stock assessment information can be found on Stock SMART.
- Scientists at NOAA’s Northeast Fisheries Science Center estimate the abundance of summer flounder using data collected during their annual bottom trawl surveys, along with data from state- and university-run surveys.
- The summer flounder stock declined to record lows in the late 1980s and early 1990s. With improved reproduction and survival rates and sustainable management, spawning stock biomass (a measure of the amount of summer flounder able to reproduce) has increased substantially.
Appearance
- Summer flounder have flat bodies.
- They are white below and some shade of brown, gray, or drab above.
- They’re nicknamed “chameleons of the sea” because they’re able to change their coloring to blend in with the texture and color of the bottom where they live.
- They also have spots on their back and can be distinguished because at least five of these dark spots are arranged in an "X" pattern.
- Summer flounder is a left-eyed flatfish (both eyes are on the left side of its body when viewed from above with the dorsal fin facing up). When larvae develop into juveniles, their right eye moves across the top of the head to the left side.
Biology
- Summer flounder grow fast and have a relatively short life, about 12 to 14 years.
- Males grow to more than 2 feet in length and females grow up to 3 feet.
- They are able to reproduce when they reach age 2 or 3.
- Summer flounder spawn in the fall and early winter when they migrate offshore.
- They spawn several times throughout the spawning season.
- Spawning peaks in October and November when water temperatures change and autumn plankton is most productive. The combination of these elements improves the chance of survival for larval summer flounder.
- Depending on their size, females have between 460,000 and more than 4 million eggs. They release the eggs into the water column and the eggs hatch in waters of the continental shelf.
- Newly hatched larvae move with the currents toward coastal areas, where they develop into juveniles.
- Summer flounder eat a mixed diet of fish and invertebrates throughout their life.
- Larval and post-larval flounder feed on zooplankton (tiny floating animals) and small crustaceans.
- Juveniles eat crustaceans and fish.
- Adults are opportunistic feeders, eating whatever food is convenient at the time, and feed mostly on fish and crustaceans.
- Summer flounder lay on the ocean floor concealed, partly by sand and partly by their coloration, and wait for their prey to swim by. When suitable prey appears, flounder ambush them.
- Larval and juvenile summer flounder are preyed upon until they grow large enough to fend for themselves. Predators include spiny dogfish, monkfish, cod, hakes, sea raven, longhorn sculpin, and fourspot flounder. Large sharks, rays, and monkfish prey on adult summer flounder.
Where They Live
Range
- Summer flounder are found in the Atlantic Ocean from Nova Scotia to the east coast of Florida.
- In U.S. waters, summer flounder are most common in the mid-Atlantic region from Cape Cod, Massachusetts, to Cape Fear, North Carolina.
Habitat
- Larval summer flounder live in estuaries and coastal lagoons.
- Juveniles burrow in the sediment in marsh creeks, seagrass beds, mud flats, and open bays, notably Pamlico Sound and Chesapeake Bay. Because this important life stage takes place near heavily populated urban areas, maintaining good water quality is important for successful growth and survival of young summer flounder.
- Adults spend most of their lives on or near the seafloor burrowing in the sand. They’re also found in marsh creeks, seagrass beds, and sand flats.
- Adult summer flounder migrate inshore and offshore seasonally with changes in water temperature. In the winter and early spring, they’re found offshore along the outer edge of the continental shelf. In late spring and early summer, they move inshore into shallow coastal waters and estuaries. Summer flounder migrate back offshore in the fall.
Fishery Management
- NOAA Fisheries, the Mid-Atlantic Fishery Management Council, and the Atlantic States Marine Fisheries Commission cooperatively manage the summer flounder fishery because significant catch of these species comes from both state waters (0–3 nautical miles offshore) and federal waters (3-200 nautical miles offshore).
- Managed under the Summer Flounder, Scup, and Black Sea Bass Fishery Management Plan:
- Using scientific data on the summer flounder resource and fishery, managers determine how much summer flounder can be harvested the following year.
- They allocate 60 percent of the annual catch limit to the commercial fishery and 40 percent to the recreational fishery.
- The commercial catch limit is further distributed among the states based on their share of commercial landings during the 1980s.
- Fish and mesh size limits protect juvenile fish and help to maintain the part of the population that is able to reproduce.
- A permit is required to sell and purchase summer flounder.
- Monitoring of sea turtle catch occurs in the southern portion of the fishery.
- There is a moratorium on entry into the commercial fishery.
- There are reporting requirements.
Harvest
- Commercial fishery:
- In 2022, commercial landings of summer flounder totaled 10 million pounds and were valued at approximately $26 million, according to the NOAA Fisheries commercial fishing landings database.
- Gear types, habitat impacts, and bycatch:
- Commercial fishermen mainly use bottom trawls to harvest summer flounder, fishing offshore in the winter and inshore in the summer.
- Bottom trawls contact the bottom and can impact bottom habitats. However, summer flounder are most common on sandy ocean bottoms, which are more resilient than other habitat types to the impacts of fishing gear.
- Bottom trawls can unintentionally catch sea turtles. Since 1992, all vessels fishing for summer flounder with bottom trawls off Virginia and North Carolina have been required to use NOAA Fisheries–approved turtle excluder devices (TEDs) in their nets. A TED is a sorting grid that is sewn into a trawl net to allow fish to pass through to the back of the net while preventing larger animals, such as turtles and sharks, from passing through by allowing them to escape through flaps above or below the TED.
- Management measures also require the mesh on fishing nets to be a certain size to prevent bycatch of juvenile summer flounder and other species.
- Recreational fishery:
- Summer flounder are one of the most popular recreational fish on the Atlantic coast.
- In 2022, recreational landings were 8.6 million pounds, according to the NOAA Fisheries recreational fishing landings database.
- Anglers fish for summer flounder from the shore, piers, and boats with hook-and-line gear.
- The recreational harvest limits for each state are based on the recreational catch in 1998.
- Regulations for the recreational fishery are typically adjusted annually. They include an annual harvest limit, closed seasons, a minimum size for landed fish, and possession limits.
- Recreational landings varied widely over the years until harvest limits were put in place in 1993.
Scientific Classification
- Summer flounder are found in the Atlantic Ocean from Nova Scotia to the east coast of Florida.
- In U.S. waters, summer flounder are most common in the mid-Atlantic region from Cape Cod, Massachusetts, to Cape Fear, North Carolina.
- Larval summer flounder live in estuaries and coastal lagoons.
- Juveniles burrow in the sediment in marsh creeks, seagrass beds, mud flats, and open bays, notably Pamlico Sound and Chesapeake Bay. Because this important life stage takes place near heavily populated urban areas, maintaining good water quality is important for successful growth and survival of young summer flounder.
- Adults spend most of their lives on or near the seafloor burrowing in the sand. They’re also found in marsh creeks, seagrass beds, and sand flats.
- Adult summer flounder migrate inshore and offshore seasonally with changes in water temperature. In the winter and early spring, they’re found offshore along the outer edge of the continental shelf. In late spring and early summer, they move inshore into shallow coastal waters and estuaries. Summer flounder migrate back offshore in the fall.
Fishery Management
- NOAA Fisheries, the Mid-Atlantic Fishery Management Council, and the Atlantic States Marine Fisheries Commission cooperatively manage the summer flounder fishery because significant catch of these species comes from both state waters (0–3 nautical miles offshore) and federal waters (3-200 nautical miles offshore).
- Managed under the Summer Flounder, Scup, and Black Sea Bass Fishery Management Plan:
- Using scientific data on the summer flounder resource and fishery, managers determine how much summer flounder can be harvested the following year.
- They allocate 60 percent of the annual catch limit to the commercial fishery and 40 percent to the recreational fishery.
- The commercial catch limit is further distributed among the states based on their share of commercial landings during the 1980s.
- Fish and mesh size limits protect juvenile fish and help to maintain the part of the population that is able to reproduce.
- A permit is required to sell and purchase summer flounder.
- Monitoring of sea turtle catch occurs in the southern portion of the fishery.
- There is a moratorium on entry into the commercial fishery.
- There are reporting requirements.
Harvest
- Commercial fishery:
- In 2022, commercial landings of summer flounder totaled 10 million pounds and were valued at approximately $26 million, according to the NOAA Fisheries commercial fishing landings database.
- Gear types, habitat impacts, and bycatch:
- Commercial fishermen mainly use bottom trawls to harvest summer flounder, fishing offshore in the winter and inshore in the summer.
- Bottom trawls contact the bottom and can impact bottom habitats. However, summer flounder are most common on sandy ocean bottoms, which are more resilient than other habitat types to the impacts of fishing gear.
- Bottom trawls can unintentionally catch sea turtles. Since 1992, all vessels fishing for summer flounder with bottom trawls off Virginia and North Carolina have been required to use NOAA Fisheries–approved turtle excluder devices (TEDs) in their nets. A TED is a sorting grid that is sewn into a trawl net to allow fish to pass through to the back of the net while preventing larger animals, such as turtles and sharks, from passing through by allowing them to escape through flaps above or below the TED.
- Management measures also require the mesh on fishing nets to be a certain size to prevent bycatch of juvenile summer flounder and other species.
- Recreational fishery:
- Summer flounder are one of the most popular recreational fish on the Atlantic coast.
- In 2022, recreational landings were 8.6 million pounds, according to the NOAA Fisheries recreational fishing landings database.
- Anglers fish for summer flounder from the shore, piers, and boats with hook-and-line gear.
- The recreational harvest limits for each state are based on the recreational catch in 1998.
- Regulations for the recreational fishery are typically adjusted annually. They include an annual harvest limit, closed seasons, a minimum size for landed fish, and possession limits.
- Recreational landings varied widely over the years until harvest limits were put in place in 1993.
Scientific Classification
| Kingdom | Animalia | Phylum | Chordata | Class | Actinopterygii | Order | Pleuronectiformes | Family | Paralichthyidae | Genus | Paralichthys | Species | dentatus |
|---|
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Seafood Facts
Is Summer Flounder Sustainable?
U.S. wild-caught summer flounder is a smart seafood choice because it is sustainably managed and responsibly harvested under U.S. regulations.
Availability
Year-round. Summer flounder is sold whole and in fillets and is available fresh or frozen.
Source
U.S. wild-caught from Maine to North Carolina.
Taste
Skin is edible. Meat has a delicate flavor.
Texture
Flaky and fine.
Color
White.
Health Benefits
Flounder is a good low-fat source of B vitamins and niacin.
Nutrition Facts
Servings: 1; Serving Weight: 100 g (raw); Calories: 91; Protein: 18.84 g; Total Fat: 1.19 g; Total Saturated Fatty Acids: 0.283 g; Carbohydrate: 0 g; Total Sugars: 0 g; Total Dietary Fiber: 0 g; Cholesterol: 48 mg; Selenium: 32.7 mcg; Sodium: 81 mgSeafood News
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Fish on display at the market. Credit: Shutterstock
Fishermen offloading. Credit: Shutterstock
Science Overview
NOAA Fisheries conducts various research activities on the biology, behavior, and population health of summer flounder. The results of this research are used to inform management decisions for this species.
For detailed information about stock status, management, assessments, and resource trends, you can search for summer flounder, and any other species of interest, using NOAA’s StockSMART web tool.
Summer Flounder Research in the Northeast
Scientists from NOAA’s Northeast Fisheries Science Center conduct annual spring and fall bottom trawl surveys in areas from just south of Cape Hatteras to Canadian waters. These survey results—along with data from surveys run by states and universities and catch data from commercial fisheries—help scientists estimate the abundance of summer flounder and other species in the Mid-Atlantic and New England.
Fishery Observer Program
The Northeast Fisheries Science Center’s Fishery Observer Program plays a vital role in the conservation and management of the fisheries from Maine to North Carolina. The program has collected information on landings and discards in the commercial summer flounder fisheries for more than 20 years.
