Summer flounder

The summer flounder or fluke (Paralichthys dentatus) is a marine flatfish that is found in the Atlantic Ocean off the East Coast of the United States and Canada. It is especially abundant in waters from North Carolina to Massachusetts.

They have laterally-compressed bodies meaning that their body is flattened side-to-side. Covering the body are eye-like spots.

Habitat

The summer flounder has a range in the western Atlantic from Nova Scotia to Florida, possibly farther south where the summer flounder may mix and be confused with its close relative the southern flounder (Paralichthys lethostigma) which lacks the eye-like spots of the summer flounder. Paralichthys dentatus is most common to the coastal and shelf waters off of the northeast U.S. where they are commonly called Fluke. In the spring months fluke leave their winter stay in the deep ocean waters, where spawning occurs, to move into the inshore waters along beaches, inlets, bays, estuaries, canals, and creeks where they will stay until autumn or even early winter.

Behaviour

Adults are highly predatory and considered mostly piscivorous. They are often lie buried with only their head exposed to ambush prey. Prey items includes sand lance, menhaden, atlantic silverside, mummichog killifish, small bluefish, porgies, squid, shrimp, and crabs. While primarily considered a bottom fish, they are rapid swimmers over short distances and can become very aggressive, feeding actively at mid-depths, even chasing prey to the surface.

They are capable of rapidly burrowing into muddy or sandy bottoms.

Like most members of the left-eye flounders, they posses exceptional capacity for dynamic camouflage being able to change the color and pattern of their dark side to match the surrounding bottom. They are able to match the substrate with a high degree of precision, including the different sizes of grains and artificial checkerboards. However since their eyes face away from the bottom, it is unknown if this process is vision-mediated.