Summer flounder, often called "fluke," is considered a good lowfat source of B vitamins and niacin. It has edible skin, and flaky white meat with a delicate flavor and fine texture. It is sold whole, in fillets, and is available fresh or frozen. Fillets are usually available in one to three ounces to six to eight ounce size ranges, alternatively small, medium, large, and jumbo sizes are offered by some suppliers. Landings are heaviest in the summer, which is generally considered to be the best time to get a deal on the fish. Some buyers say the best quality summer flounder comes from pound nets in the mid-Atlantic region. Live summer flounder is exported to Japan for sashimi. Summer flounder may be easily substituted for other flounders.
Key sustainability sourcing notes for summer flounder based on production from 2014-2016 and the most recent 2019 Seafood Watch assessments:
Less than 5% of U.S. summer flounder landings meet a Seafood Watch 'Best Choice (green)' rating (handline-caught) with ~35% from Rhode Island and ~20% each from New York and Massachusetts
Approximately 65% of U.S. summer flounder landings meet a Seafood Watch "Good Alternative (yellow)" rating (bottom trawl, bottom gillnet, and trap net)
~30% of U.S. summer flounder meets an unknown/unrated categorization
10 U.S. states report landings for summer flounder, ~80-85% of summer flounder comes from 4 states: North Carolina (~30%), Virginia (~20%), Rhode Island and New Jersey ~15% each
2016 U.S. summer flounder landings have decreased ~30% from 2014 and ~40% from 2012, with a decrease in landings every year from 2012 to 2016
Summer flounder grow fast with males reaching lengths of 2 feet and females 3 feet. The fish reach maturity between 2 & 3 and life expectancy on average of 12 to 14 years. Summer flounder spawn several times in the fall and early winter when water temperatures change and plankton productivity peaks. Summer flounder prey on both fish and invertebrates throughout their life, but are mostly opportunistic feeders. Summer flounder are a food source for spiny dogfish, monkfish, cod, sharks, and rays.
Summer flounder are found from Nova Scotia to the east coast of Florida and are most common in the U.S. between Cape Cod and Cape Fear. Juvenile summer flounder inhabit marshes, seagrass, mud flats, and open bays. This important life stage takes place notably in Chesapeake Bay and Pamlico Sound, and because of these populated urban areas, water quality is critical for survival of juvenile fish. Adult summer flounder are found mostly on sandy sea bottoms and migrate inshore (late spring and summer) and offshore (late fall through early spring) seasonally with changes in water temperature.
Science & Management
Summer flounder stock abundance is estimated from annual bottom trawl surveys, along with data from state agencies and university research. Management measures set aside part of the summer flounder quota to be used for research that furthers the understanding of the summer flounder fishery.
Because summer flounder is caught in both state and federal waters, summer flounder is managed by the Atlantic States Marine Fisheries Commission (0-3 miles offshore) and NOAA Fisheries' Mid-Atlantic Fishery Management Council (3-200 miles offshore). The allocation for summer flounder is split between the commercial fishery (60%) and recreational fishery (40%). States divide the commercial share based on % share of landings from the 1980s. Currently there is a moratorium on entry into the commercial fishery and there are special monitoring requirements for sea turtles in the southern portion of the fishery. Measures are also taken as a management precaution on mesh size requirements on fishing nets to prevent bycatch of both juvenile summer flounder and other species.
Summer flounder is a bottom-dwelling type of flatfish found along the Northwest Atlantic that is most prevalent in the U.S. Mid-Atlantic region. Despite characteristics such as high fecundity and early maturation, summer flounder is moderately vulnerable to fishing pressure overall, according to Seafood Watch. Following low population levels in the 1980s and 1990s, the stock has been rebuilding in the United States. A 2015 stock assessment showed that summer flounder are not overfished, but are subject to overfishing. Seafood Watch reports from 2016 gave summer flounder an avoid rating with the exception of the North Atlantic handline fishery, which received a good alternative rating.
Habitat impacts (Wild)
Most summer flounder are caught with bottom trawls although bottom gillnets, trap nets, and handlines are also used. The bottom trawls that target flatfish can cause significant damage to the seafloor, but the sandy bottom areas that summer flounder prefer tend to recover faster. In addition, areas of these fishing grounds are off-limits to trawl gears, Seafood Watch reported in 2016. The handlines, trap nets, and bottom gillnets used for summer flounder have much less impact on sensitive marine habitats, causing low concern, according to Seafood Watch.
Summer flounder are primarily caught using bottom trawls, which carries a risk of sea turtle bycatch. Since 1992, bottom trawl vessels off the coasts of North Carolina and Virginia have been required to use NOAA-approved turtle extruder devices in their nets to minimize bycatch. Seafood Watch reported concern about incidental catches of bottlenose dolphin in the trap net fisheries. Several protected, threatened, and endangered species such as Atlantic sturgeon, sea turtles, and marine mammals have been caught in gillnet fisheries.
Since summer flounder are found in both state and federal waters, they are managed by the Atlantic States Marine Fisheries Commission, the Mid-Atlantic Fishery Management Council, and NOAA Fisheries. Management measures include catch limits, reporting requirements, permit requirements, mesh size limits, scientific monitoring and a moratorium on entry into the commercial fishery. Sea turtle catches are also monitored in the southern part of the fishery. A rebuilding plan introduced in 1993 aimed to help stocks recover from overfishing. While summer flounder abundance has greatly increased since then, a 2015 stock assessment showed that abundance remained below the target level, Seafood Watch reported. Generally, Seafood Watch found the management measures for this vulnerable species to range from moderately to highly effective.