Hippoglossus hippoglossus

World record halibut, 9'5", 459 pounds, 31 years old, Caught by Jack Tragis, June 11, 1996, Unalaska, Alaska.

The Halibut is the largest of all flat fish, with an average weight of about 25 - 30 lb (11 - 13½ kg), but they can grow to be as much as 900 lbs (272kg) The Halibut is blackish-grey on the top side and off-white on the underbelly side. When the Halibut is born the eyes are on both sides of its head so it has to swim like a salmon. After about 6 months one eye will migrate to the other side of its head, making it look more like the flounder. This happens at the same time that the stationary eyed side begins to develop a blackish-grey pigment while the other side remains white. This disguises a halibut from above (blending with the ocean floor) and from below (blending into the light from the sky)--Wikipedia