I thought this brute might have been a rare Patagonian Tooth fish, but no. It’s called a Rudder fish. The big eye and dark color suggests deep water, which is true. Instead of a gas filled ‘air’ bladder, this predator has a bladder filled with oil which enables the fish to change depths very fast with no ill-effect. They probably chase small fish or squid at night from deep water towards the surface. Other fish would have to give up the chase as pressures changed. Not these fellows. The downside is their flesh is contains a wax – non digestible. Eat too much and you’ll be running for a toilet.
It looks like a giant parrot fish – it’s the Hump Head Maori Wrasse which has blueish meat. Recently a protected species in Australia due to their popularity with spear fishermen. Thought to be extremely ‘shy’ but with trust they are like huge pets. Worth a fortune as photographic subjects underwater. The first tame specimens were seen in The Red Sea about 35 years ago. The Cod Hole, north of Cairns (Australia) has some tame examples. Are they good to eat? Apparently yes.click for larger view