Its nickname “chameleon of the sea” is well deserved. Seemingly gliding gracefully across the bottom with little effort, it can change its color from brown, gray green or even darker to blend with the pattern and color of the bottom on which it lands. To further conceal itself, it flips its body, raising the sediments and buries itself, especially in fine sand, with only its eyes visible. If approached too closely by a Scuba diver, it might dart out, but with a surprising bit of luck –“a fluke,” – it may simply stare back into the eyes of its human intruder.
The “fluke” is of course a summer flounder. There are many other examples of sea creatures that change their color to blend with their surroundings. Squids and octopuses are well known for their ability to camouflage themselves. Summer flounders do so to protect themselves from predators such as sharks, rays and monkfish. But perhaps even more so, they conceal themselves from their prey, which includes crabs, sand and grass shrimps, squid, snails and fish. They are aggressive predators. Lying perfectly concealed, they wait for passing prey that comes into range. They then dart out to ambush the creature if it is suitable for their next meal. Summer flounders are also fast swimmers. They frequently rise toward the surface in pursuit of schools of small fish such as Atlantic silversides and bay anchovies. Flukes are well armed for capturing their prey. They have a large mouth with sharp cone shaped teeth in their upper and lower jaws.
Summer flounders are also called “doormats” when they weigh in at over 8 pounds. The species ranges from Nova Scotia, Canada to the east coast of Florida. They are, however, most abundant from Cape Cod, Massachusetts to Cape Fear, North Carolina. On average, they grow 14 to 37 inches long with females growing larger than males. Their life span is estimated to be between 12 to 14 or more years.
The flounders begin spawning when they are about 12 inches in length, at around 2 to 3 years of age. In the fall, adults migrate offshore where mature females release 400,000 to 4 million eggs, in up to six separate batches. When first hatched, the larvae have eyes on both sides of their head, like most other species of fish. As the larvae mature, however, the right eye migrates to the left side. The young then settle to the bottom, lying on their right side. Carried by currents, the young make their way toward the shoreline where they settle in coastal bays. They remain there until about the end of their first year. Some then join adults on their fall-season offshore migration.
Flukes are an important part of commercial and recreational fisheries. In southern New England, the University of Rhode Island reports that their resale value is greater than any other species of regional food fish.
Commercially, they are mainly taken offshore with bottom-towed otter trawls. In estuaries, gillnets and pound nets are used to capture them. In 2019, among all of the Atlantic states, the fishing fleet out of Point Judith, Rhode Island landed the greatest percentages of summer flounder.
Sportfishing for summer flounder can very rewarding; they are fun to catch and provide great eating! They tend to gather on sand and mud bottoms, near river mouths, on sandy shoals, channel drop-offs and around rock reefs or shipwrecks, at depths of 15 to 50 or more feet. If birds are spotted diving on schools of baitfish, it can be an opportunity to catch a fluke with a rig that usually works well. Using bucktail tackle with a small strip of spearing (Atlantic silverside), mackerel, other local fish or squid, can help land a hungry fluke. If fishing for doormats, larger baits such as 8-inch snappers work best. When hooking into a fluke keep the rod tip up and don’t allow any slack in the line. It is then best to pick up the catch with a large net.
Drift fishing for summer flounder is often recommended by many recreational fishermen. For doormat-sized fluke, drifting works best during the beginning hour and end hour of a tide when the current is not too strong. At mid-tide, with its stronger current, smaller flounder tend to strike more frequently.
The coastal waters of New Jersey and New York are the sites of the highest percentage of recreationally landed summer flounder. In 2019, according to a survey by the National Marine Fisheries Service, about 90-percent of the flukes were taken from boats. The other 10-percent were landed from shore.
In 1975, the International Game Fish Association (IGFA) designated the summer flounder caught by Captain Charles Nappi as the world record. Weighing in at 22.7 pounds, it was brought in about 2 miles south-west of Montauk Point, New York, at the Frisbee Grounds. Known as the “Duke of Fluke,” Nappi also recommends Ambrose Channel in the New York Bight, Massachusetts’ Nantucket Shoals and Block Island for doormat-sized summer flounder.
In 2007, while fishing off Shrewsbury Rocks, Monmouth County, New Jersey, Monica Oswald nearly set a new world record for summer flounder. It weighed in at 24.5 pounds and was 38.5 inches in length yet was not qualified by the IGFA. Unfortunately, while bringing in her catch, Oswald rested her pole on the boat’s rail while bringing in her fish. She thus lost out on her record doormat. According to IGFA’s rules, a record is disqualified when “Resting the rod in a rod holder, on the gunwale of the boat, or any other object while playing the fish.”
In Massachusetts’ waters, the state’s record fluke weighed in at 21 pounds, 8 ounces (Joseph Czapiga, 1975); Rhode Island’s record, 17 pounds, 8 ounces (G. Farmen, 1962); Connecticut’s record, 14.85 pounds, 31 inches in length (Tobey Sweet, 2013); New Jersey’s record, 19 pounds, 12 ounces (Walter Lubin, 1953).
Each state designates its season, minimum size and limit per person. Be sure to check with that state’s authorities for summer flounder regulations.