Winter Flounder
A cold-water flatfish of the western North Atlantic, the winter flounder moves inshore into estuaries and back bays as temperatures drop — making it one of the few species that fishes best in the chill of late winter and early spring.
Smaller-mouthed and more deliberate than its cousin the summer flounder, it rewards anglers who understand soft-bottom habitat and keep their bait on the bottom.
Scientific Name: Pseudopleuronectes americanus
Also known as Blackback, Black Flounder, Mud Dab, Lemon Sole
- A right-eyed flatfish — both eyes sit on the right side of the body — with an oval, thick profile and a straight lateral line running from head to tail.
- Upper-side color shifts with habitat: muddy brown, olive green, dark slate, or nearly black; the underside is white. Dorsal and anal fins are often tinged pink, red, or yellow.
- The small, close-set mouth is the key field mark separating it from the summer flounder (fluke), which has a noticeably larger mouth and teeth.
- Common catches run 1–3 lbs and up to 18 inches; the species can reach 8 lbs and live 15–18 years, though fish that size are rare today.
What to know
Habitat Distribution
- Native to the western North Atlantic coast from Labrador south to Georgia, with the core population concentrated from New England through the Mid-Atlantic seaboard.
- A bottom-dwelling species of estuaries, coastal bays, and offshore banks — found anywhere from the shallows down to roughly 470 feet, though inshore anglers encounter them in much shallower water.
- Prefers soft substrates: mud, silt, and mixed mud-shell bottoms are the most productive ground, though fish will also hold over sand.
Specific Spots
- Back-bay flats with dark, muddy bottoms absorb heat from the sun and warm faster in early spring — flounder stage here before moving to deeper water as temperatures climb.
- Adults lie half-buried in silt or sand, so any soft-bottom depression, channel edge, or tidal flat with a nearby drop-off concentrates fish that can slide between feeding depth and thermal refuge.
- Juveniles use seagrass beds and macroalgal patches as nursery cover; adult fish will hold along the edges of these same vegetated areas where invertebrate prey is dense.
Winter Flounder FAQ
Answers from onWater's species guide.
What are the best lures and bait for Winter Flounder?
Sea worms, bloodworms and sandworms, are the standard bait across the range. Fresh worms on a small hook (size 6–8) fished hard on the bottom consistently outperform everything else.
What do Winter Flounder eat?
Feeds on bottom-dwelling invertebrates, polychaete worms (bloodworms, sandworms), shrimp, amphipods, small crabs, clam siphon tips, and mussels. This is exactly why sea worms and clam strips are the go-to baits: they match what the fish is already rooting for in the mud.
Where do Winter Flounder live?
Native to the western North Atlantic coast from Labrador south to Georgia, with the core population concentrated from New England through the Mid-Atlantic seaboard.
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