Summer Flounder (Fluke)

Summer flounder are a medium-sized flatfish abundant in the Mid-Atlantic region, which support important recreational and commercial fisheries in states between Massachusetts and North Carolina.

Distribution has varied quite a bit over the years. Back in the 90s, when size limit was 14” and the stock was undoubtedly depleted, the center of abundance was off of Delaware and Southern New Jersey.

After 2000, in an effort to rebuild the stock, managers imposed more restrictive regulations on the recreational and commercial fisheries. In response, the stock recovered, larger and older fish became more abundant, and the center of abundance, particularly for those larger fish, shifted toward New York and Southern New England.

Recreational harvest has been allocated among the states based on each state’s estimated landings in 1998 baseline. Under such system, New Jersey receives the largest share, 39% of the overall landings, even though the distribution of flounder has changed over the years.

Based on catch data from 1980 to 1989, 60 percent of landings are allocated to the commercial side while the recreational side gets 40 percent.

On the commercial side, two large-scale commercial bottom-trawl fisheries exist — a winter offshore fishery and a summer inshore one. In some regions, limited pound net (trap) and gillnet fisheries exist inshore, but are much smaller in scale.

The recreational fishery has historically been prosecuted from May to October in the Mid Atlantic.

Fluke are particularly important to anglers as they are good table fare and, unlike other popular recreationally-targeted fish, are relatively easy to fish for and do not require sophisticated techniques. Even the most novice angler can participate without having to learn the ropes.

General availability makes them a popular species with anglers as well, as fluke are aggressive feeders throughout the day and tend to feed even in the afternoon sun.

When the stock is abundant, they exist in good numbers in the bays and inlets throughout the spring, summer and fall seasons, although in recent years, due to declining abundance, keeper-size fish have typically been restricted to deeper water on the ocean side.

Biology and Habitat

Adult summer flounder exhibit very deliberate seasonal movements. They populate shallow coastal and estuarine waters in the spring, summer, and fall, but migrate offshore to spawn during the late fall and winter. Newly hatched larvae migrate inshore to coastal and estuarine areas in the early spring.

Most female fluke become fertile when about two years old (14 to 15”). Male and female growth ratios vary substantially, with males growing more slowly (up to roughly 18” or around 3 pounds) and living substantially shorter lives (about 10 years), whereas females may live for up to 20 years and can weigh as much as 25 lb.

Fluke are opportunistic feeders, preying on small fish, squid, sea worms, shrimp, and other crustaceans. While they spend most of their lives as ambush predators that burrow into the substrate and launch sudden attacks on their prey, when dense schools of baitfish are present, it is not unusual for fluke to rise higher up in the water column and engage in more active pursuit.


Summer flounder are managed by the NOAA Fisheries, acting upon advice from the Mid-Atlantic Fishery Management Council (Council) and the Atlantic States Marine Fisheries Commission (Commission). Such “cooperative management” was developed because a significant portion of fish is taken from both state (0-3 miles offshore) and federal waters (3- 200 miles offshore).

A joint Fishery Management Plan (FMP) for summer flounder was implemented in 1988. The two management bodies currently work cooperatively to develop commercial quotas and recreational harvest targets under this plan.

Each year, the Council’s Scientific and Statistical Committee (SSC) recommends annual Acceptable Biological Catch (ABC) levels for summer flounder, which then need to be approved by the Council and Commission and submitted to NOAA Fisheries for final approval and implementation.

The Council and Commission vote annually on whether to manage the recreational fishery under a set of coast-wide regulations or “conservation equivalency,” which allows states to make their own regulations based on the aforementioned 1998 baseline.

Under such “conservation equivalency,” state- or region- specific regulations can be developed through the Commission’s management process, but ultimately, NOAA Fisheries needs to approve them. To get such approval, the combined state or regional regulations must achieve the same level of conservation as would Council-approved coast-wide measures.

From 2001 to 2013, the recreational fishery has been managed using conservation equivalency, with each state being granted a share of the harvest based on the 1998 baseline year, which disadvantaged several states, particularly New York, given the current distribution of fish.

Since 2014, state-by-state management has been replaced by a regional approach, which is generally thought to provide a more equitable distribution of the resource. States within each region must have identical size limits, possession limits, and season lengths, which eliminate sharp disparities between the regulations of states sharing common waters.

Stock Status

The summer flounder stock declined greatly through the 1980s, bottoming out in 1989. It did not become subject to a meaningful stock rebuilding plan until 2000.

Such rebuilding happened only because a lawsuit by the Natural Resource Defense Council forced the agency to comply with the Sustainable Fisheries Act of 1996, which strengthened requirements to prevent overfishing and rebuild overfished stocks.

Catch limits and real accountability measures, required as part of the Magnuson-Stevens Act Reauthorization in 2007, allowed the stock to climb back up to healthy levels, and it was declared rebuilt in 2011, based on an assessment update with data through 2010.

Anglers saw greatly increased opportunity to catch summer flounder over a broad range of habitats as a result.

However, in the last several years there’s been a definite decline in summer founder abundance.

That’s because after 2009, the summer flounder stock has experienced 6 years of poor recruitment (aka poor spawning success).

Scientists have been unable to determine, with any certainty, why that’s happened. Given the scale of illegal fishing (e.g. recent Research Set Aside violations) it’s not unreasonable to believe it could be due to large-scale illegal fishing mortality. But there’s also some evidence that summer flounder’s recruitment issues could be due to warming waters or ocean acidification due to climate change.

Yet such periods of poor recruitment certainly aren’t unheard of, and recruitment usually rebounds at some point.

Recent Stock Assessment

The most recent benchmark stock assessment was completed in 2013. In June of 2016, NOAA Fisheries completed a stock assessment update, which showed biomass has been trending down since 2010. While the summer flounder stock had not dipped below a scientifically defined “overfished” reference point, we were still “overfishing” (taking fish out of the population faster than they could replace themselves). That said, it was clear that harvest needed to be significantly reduced.

The Commission and the Council approved an approximate 29% decrease in 2016 landings, yet recreational fishing surveys showed that the recreational sector had significantly underfished their harvest limit in the prior year, so more restrictive regulations were not imposed.

Fast forward to 2017… Poor recruitment continues, and those same surveys show that anglers exceeded their harvest limit (in some states, by a lot) in 2016. And so we need to take another 30% reduction in 2017, plus another 10% on top of that to account for the overage.

In February of this year, the Commission approved an option that offers a near coast-wide one‐inch size limit increase and bag limit reduction to no more than four fish.

While constraining, this option offers the longest seasons and what most believe are reasonable size and bag limits across the board. While this option supports the biological conclusion that a 30% reduction is needed, it doesn’t address the 2016 overage. So, at the time of this writing, we’re still not sure NOAA will approve it.

All indications, however, are that such option may be accepted. Managers and stakeholders have expressed a great deal of uncertainly with respect to the 2016 catch estimates, and continuing analysis of such estimates has revealed some retrospective issues which may ultimately negate the alleged 10% overage.

Given the extraordinary opposition to any reductions this time around, this was arguably a good compromise, and may in the end, preserve federal law.

Comprehensive Summer Flounder Management Plan

The Mid-Atlantic Fishery Management Council and the Atlantic States Marine Fisheries Commission are currently developing an amendment to the Summer Flounder, Scup, and Black Sea Bass Fishery Management Plan in order to perform a comprehensive review of all aspects of summer flounder management.

Based on feedback received during the public scoping process, the Council and Commission identified four general categories of issues to be addressed in the amendment: Fishery Management Plan (FMP) goals and objectives, quota allocation between the commercial and recreational sectors, and commercial and recreational management measures and strategies. In addition, the Council and Commission indicated that they may also address issues related to discards, ecosystems, and catch monitoring under the umbrella of the categories listed above.

The timeline for completion of this action will likely be two years.

Recent Summer Flounder Blog Posts

From the “From the Waterfront” blog of the Marine Fish Conservation Network.


  1. Pingback/Trackback
    Apr 17, 2017 at 8:46 pm

    H.R. 1411 “Transparent Summer Flounder Quotas Act” – Fissues

  2. Pingback/Trackback
    Apr 20, 2017 at 7:46 pm

    NOAA Accepts ASMFC Summer Flounder Recommendations – Fissues