If anyone has a problem telling flounder from fluke...I have two foolproof ways of telling them apart.
First, look at the eyes with relation to the mouth. As Sandman stated earlier fluke or summer flounder are left-handed; that is, it lies on the bottom on its right side, with its eyes on its left-hand side, and its abdomen on its left. Winter flounder or blackback flounder are referred to as a right handed flounder because the eyes are located on its right side when the fish is pointing to the right.
If you can't tell your right from your left the second surefire way to tell the difference is to stick your finger in its mouth. If it comes out all bloody any perforated you know it's a fluke.
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