Gulf Flounder fish identification, Habitats, Fishing methods, fish characteristics
The Gulf flounder is a member of the Bothidae family of left-eyed flounder, is one of the smaller fish in a family and an excellent table fish. The average fish is under 2 pounds weight and length 6 to 10 inches. Light brown above, with the scales usually more or less outlined with darker brown; brownish white below. Gulf flounder spend the warmer months in coastal embayments and sometimes in nearshore shelf waters, and migrate offshore during the fall as waters cool.
Gulf flounder, Paralichthys albigutta, also known as Sand flounder, flounder, fluke, is a marine fish widely distributed eastern coast of America from Cape Lookout, North Carolina to Florida, also to Corpus Christi, Texas, Gulf of Mexico and western Caribbean to Panama. Occasionally enter the western Bahamas. Rarely enters waters of reduced salinities, and never enters fresh-water.
The Gulf flounder has oval, moderately elongate and very thin body (depth 2.1 to 2.6 in length - 39 to 47%). Dorsal profile of head is straight. Eyes on the left-hand side and viscera at the left-hand edge as the fish lies have diameter 4.8 to 6.0 in head length (26-35% of length); interorbital space flat and narrow (smaller than eye diameter - 17 to 21% of head length). Mouth is large and wide, gaping back as far as the forward edge of the eye, with single series of strong canine-like teeth; upper jaw length is 47 to 50% of head length, extending posteriorly to a vertical through posterior margin of eye on species up to 125mm in length, and farther beyond on larger species (upper jaw length highly variable). Maxilla extending to or beyond vertical through posterior margin of lower eye. Ocular-side lateral line is forming steep arch above pectoral fin. Lateral line is nearly straight. The long (ventral and dorsal) fins are of moderate breadth. Dorsal-fin origin over the forward margin of the eye is about equal with vertical through nostrils. Both of its pectoral fins well developed, though the one on the eyed side is significantly larger than its mate on the blind side. Pectoral-fin rays is short (tip not reaching to straight portion of lateral line on ocular side). The scales along the lateral line are very large.
There are 3 ocellated black spots on eyed side of the body: 1 on upper side, a 2nd on posterior lateral line and the 3-rd on lower side. Spots may be pale in large species. There are many small spots and flecks on the rest of body. Jaws are large with upper jaw extending beyond rear edge of lower eye. Upper eye located directly over lower eye.
The eyes are on the left side.
71 to 86 (75-81) Dorsal Fin Rays.
53 to 63 (56-61) Anal Fin Rays.
10 to 12 Pectoral Fin Rays.
The caudal fin is rounded.
Max Size: 71cm; common 35cm.
Large 47-60 (52-57) scales on nearly straight lateral line.
9 to 12 (10-11) gill rakers on lower limb of first gill arch.
Vertebrae 10 + 27
The Gulf flounder has ocular side brown, varying in tone with the substrate; with many white spots and blotches over the body and fins, and 3 most prominent ocellated dark spots forming a triangle (a spot above and below lateral line and third spot on middle of straight portion of lateral line); spots may be faint in adults. It also has numerous white spots scattered over body and fins. The Gulf flounder can change their color to match the bottom.
This little flatfish very similar to the Summer Flounder, four-spotted, and sand flounders in its left-handedness. But it is distinguishable from all of these by its nearly straight lateral line; by the great disparity in size between its two pectoral fins; and by its very large scales. Its narrow shape and the fact that none of its dorsal fin rays are branched are further points of distinction between it and the sand flounder; also it is much smaller at maturity than any of the flatfishes.
The Gulf flounder inhabits mainly hard, sandy bottoms on the inner continental shelf from 19 to 130 m, often range into tidal reefs and are occasionally found around nearshore rocky reefs. Juveniles inhabit high salinity seagrass systems. Adults migrate offshore to spawn in late autumn and winter and re-enter bays during April to July.
They feed primarily on amphipods, mysids and other small crustaceans at smaller sizes (less than 5 cm total lengths); at larger sizes feeds primarily on fish.
Females mature by age 2 at sizes as small as 14.5 cm; size at 50% maturity is 35 to 38 cm total length. The average length of 2-year-old individuals is around 35 cm, and the average length of 3-year-olds to be about 40 cm. Males attains maturity at 30 to 35 cm total length. Spawning occurs offshore in the Gulf of Mexico at depths of 20 to 60m during late autumn and winter; highest spawning frequency observed during late-October to mid-December in Texas, with spawning activity tapering off in February. Larvae and young migrate inshore during January and February with February being the month of maximum immigration (water temperatures about 16C). Females grow faster and attain larger sizes than do males.
Larval gulf flounder appear in the eastern Gulf of Mexico from December to early March, and juveniles are seen in bays and estuaries in January throughout their range, with peak movement usually occurring in early February. Juvenile gulf flounder, like southern flounder, begin immigrating into Aransas Bay when water temperatures reach 14-16 C.
Flounder are caught by sport fishermen using various techniques, such as still fishing, drift fishing, casting from shore, and angling from piers and banks using live, fresh, or frozen baits cast 6 t o 18 inches above the bottom. Another popular method for catching these fish in some areas is by gigging at night in shallow water, using a long-handled, three-pronged spear and a torch or flashlight. Sport fishing usually begins in the spring (when the fish return from deeper waters offshore, where they have spent the winter), and continues in to the fall.