Flounder Guide — Biloxi, MS

Flounder in the Back Bay of Biloxi are one of the most underrated inshore bites on the Mississippi Gulf Coast. Most anglers target speckled trout and redfish and walk right past the structure where flounder are sitting. Get the structure right and you will catch flounder, not sometimes, but consistently, regardless of tide and regardless of time of day.

Flounder are not like specks or reds. They do not chase bait across open water. They find a piece of structure with a current break, drop to the bottom, and wait. When something comes within range, they take it. That behavior makes them more predictable than other inshore species. If a bridge piling or bulkhead has the right depth alongside it and any bait moving through the area, there is almost certainly a flounder sitting on the bottom nearby.

The Back Bay holds flounder year-round from late winter through late fall. The cutoff is water temperature. Once ambient temps drop consistently below 60 degrees F, the fish push out of the bay toward warmer water. From late February or early March through November, depending on the year, flounder are catchable in the Back Bay. You do not need a specific season or tide phase the way you would targeting specks on the flats.

The best structure is anything that puts vertical concrete or wood in the water near depth. Bridge pilings are the most obvious. The Biloxi Bay Bridge and any older trestle remnants both hold fish. Pier pilings at marinas and working docks are equally productive and often see less pressure. Bulkheads and concrete seawalls are worth fishing anywhere the water alongside them runs 4 feet or deeper. Shallow bulkheads in 2 feet of water hold far fewer fish than a deep commercial bulkhead with 6 to 8 feet of water right against the wall. Concrete water breaks and coastal armoring structures scattered through the bay also hold fish. The depth alongside the structure matters more than the structure type itself.

Rigging is straightforward. Use a basic bottom setup: a fluorocarbon leader in 20 to 30 lb, 6 to 8 inches long, with a live bait hook in size 1/0 or 2/0. Add an egg sinker above the swivel, enough to reach the bottom and stay there, typically a half ounce to an ounce in the bay. The short leader keeps the bait tight to the bottom where flounder are sitting but gives the shrimp enough freedom to move and put scent in the water. Live gulf shrimp are the best bait. Fresh dead shrimp work too. Flounder are not as selective as other species. The key is keeping the bait on or very near the bottom. A flounder will not chase a bait suspended 3 feet off the structure.

For inshore structure fishing in the Back Bay, a medium spinning setup handles everything you will encounter. The Penn Pursuit IV spinning combo with 10 to 15 lb braid and a fluorocarbon leader has the sensitivity to feel a flounder pick up the bait and enough backbone to pull fish away from pilings before they wrap you. Flounder do not make long runs, but they go flat and heavy when they feel the hook, and pulling one off a piling takes more pressure than most people expect.

Moving current improves the bite. When water is moving through the bay on an incoming or outgoing tide, baitfish get pushed along the structure and flounder position themselves on the down-current side of a piling or wall to intercept whatever comes past. With live shrimp on a flat tide you will still catch fish. Flounder are waiting regardless. But moving water concentrates the bite and makes finding active fish faster. Work the shadow line on a piling, cast uptide, and let the bait drift along the face of the structure down to the bottom.

Night fishing in the Back Bay adds another dimension to the flounder bite. Any light near the water draws baitfish, and flounder follow. A light at a marina, pier, or any structure over the water, or a submersible fishing light dropped near your bait, all work. Fish the edge where the light meets dark water. Flounder sit just outside the lit zone and pick off bait moving through. Night fishing is especially productive in summer when daytime heat pushes water temperatures up and the daytime bite slows.

One local recommendation worth considering: if a flounder comes up just over the 12 inch legal limit, think about putting it back. If you are on the right structure and the bite is going, there are larger fish in the same area. Fish that are 16 inches and up are worth targeting, and worth releasing the smaller ones to get there. A 16 inch flounder versus a 12 inch flounder may not sound like much, but with the shape of a flounder it is a significant difference in meat. You spend the same amount of time cleaning and prepping either fish, but you gain a lot more at the table. Some local anglers who have fished the Back Bay for years will only keep one fish at 16 inches or better and release everything else. It sounds strict, but that practice is part of what keeps the 22 inch, 5 pound flounder in the bay. The fish that size are in the same spots. They just got selective about what they waited for. The same structure-first approach pays off at Grand Isle as well — different water, same fish behavior.

Mississippi flounder have a minimum size of 12 inches total length and a daily bag limit of 10 fish per person. The season is open year-round. Always verify current regulations with the Mississippi Department of Marine Resources before heading out.