Summer Flounder
The summer flounder, most commonly called fluke, is a member of the Bothidae family of flatfish (see), or left-eyed flounder. Like other flatfish, the summer flounder undergoes a unique maturation from egg to adult flounder in which one eye migrates to the opposite side of the head. It is the most northerly and perhaps abundant of the three bothid species, as well as the largest and most prized flatfish caught in the mid-Atlantic region of the United States.
Fishing for summer flounder off jetties and bridges is a mainstay of Mid-Atlantic coastal sportfishing and a prominent commercial catch, primarily taken by otter trawl. Anglers in the Mid-Atlantic harvest a significant proportion of the total catch, usually about 40 percent, and in some years the recreational take has exceeded the commercial take.
Although not a powerful fighter, this species provides spirited and often dependable action. The meat is firm, white, and delicately flavored, and although some complain about the many bones (as with all flounder) and a dryness of the meat, proper filleting and moisture-retaining cooking methods can eliminate those issues.
Identification — The body is wide and somewhat flattened, rimmed by long dorsal and anal fins. Its mouth is large and well equipped with teeth. The eyes are on the left side of the body, and close together. The teeth are well developed on the right side of the jaw. Its background coloring is usually gray, brown, or olive, but it adjusts to the environment to keep the fish hidden by camouflage. There are also many eyespots that change color. The blind side is white and relatively featureless. The dorsal fin has 85 to 94 rays; the anal fin has 60 to 63 rays. There are only 5 or 6 gill rakers on the upper limb of the first arch and 11 to 21 on the lower limb.
In addition to their different color patterns, the three species of bothids can be distinguished by the number of gill rakers, anal fin rays, and lateral-line scales they possess. Summer flounder have the most eyespots, gulf flounder (see: flounder, gulf) have several eyespots, and southern flounder (see: flounder, southern) lack conspicuous spots.
Size/Age — The average summer flounder weighs 2 to 5 pounds, the latter being about 23 inches long. It is capable of growing to 35 inches in length but rarely does, and the all-tackle world record is a 22-pound, 7-ounce fish caught at Montauk, New York. Historical data indicate that female summer flounder may live up to 20 years, but males rarely exceed 7 years of age. Growth rates differ appreciably between the sexes; females attain weights up to 26 pounds.
Distribution — The summer flounder occurs in the western Atlantic from Maine to South Carolina and possibly to northeast Florida, and is most abundant from Cape Cod to North Carolina.
Habitat — A bottom-dwelling fish, the summer flounder prefers sandy or muddy bottoms and is common in the summer months in bays, harbors, estuaries, canals, creeks, and along shorelines, as well as in the vicinity of piers and bridges or near patches of eelgrass or other vegetation. It typically prefers relatively shallow waters and depths of up to 100 feet during warmer months, then moves offshore in winter to deeper, cooler water of 150 to 500 feet.
Life history/Behavior — Sexually maturity is reached at age 3. Spawning takes place during the fall and winter while the fish are moving offshore into deeper water or when they reach their winter location. The eggs, which float near the surface, hatch in three to four days, producing larvae shaped more like conventional fish than flatfish. Water currents carry newly hatched flounder into the estuaries and sounds, where they undergo a transformation in shape and become bottom dwellers.
Food and feeding habits — Adults are largely piscivorous and highly predatory, feeding actively in midwater as well as on the bottom. Extremely fast swimmers, they often chase baitfish at the surface, which is not characteristic of most other flatfish. Fluke also bury themselves quickly, using undulating movements of their fins to throw sand or silt on their backs. The eyes remain uncovered and watch carefully for dinner prospects. Fluke are known to eat what is available, including shrimp, crabs, menhaden, anchovies, silversides, sand launce, killifish, weakfish, hake, and other flounder.
Angling — Although fluke can be caught from shore, fishing is usually best from a boat in 8 feet or more of water during the summer. This is especially true when water temperatures climb above 75°F, because the fish seek the cooler depths.
Commonly used baits are minnows, shrimp, and squid; artificial lures that imitate these items are also effective. A line is generally rigged with two leaders on a vertical spreader so that one hook is fished on or near the bottom, while the second is held about 1 foot off the bottom. If an artificial lure is used in combination with bait, it is attached to the upper leader so it stays off the bottom and can move realistically in the current. A sinker of sufficient size must be used so the line stays on the bottom even when there is a strong tidal flow.
Unless flounder are known to be in a certain area, it is usually best to drift for them, thereby covering a large area. Likely spots to try include places with rough or irregular bottoms, in or near inlets, and around pilings, wrecks, and jetties. Food is abundant in these locations. If you are fishing in one spot, it helps to jig the line up and down so the bait does not lie motionless on the bottom, as fluke (and other flatfish) are often attracted by movement.