As I wrote in a previous post there is a special ecotype of Orca in the Ross Sea which might well be a distinct subspecies. This type of Orca is a lot smaller as the other and specialises on fish. These fish, ice fish, play a very important role in the food web of the Ross Sea. One of the most important species is the Antarctic Silverfish, one of the key species in the food web. Another one is the much larger Antarctic Toothfish, another top predator. These fish are all belonging to the sub order Notothenioidei, a group of fish with special proteins in their blood that keeps it from freezing in the very cold waters of the Southern Ocean. Many species predate on them, amongst which this special type of Orca.