 Around five to six weeks after hatching, the left eye of the larval flounder begins to migrate to the right side of the body.The “flounder-like” juveniles then settle onto the seafloor and move into saltwater coves, coastal salt ponds, estuaries, and protected bays, where they may grow up to 100 mm within the first year.Adult winter flounder may grow as large as 70 cm and reach ages of 15+ years.