Killer Whales are really fascinating animals.
According to Wikipedia : “Killer whales are highly social; some populations are composed of matrilineal family groups which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviors, which are often specific to a particular group and passed across generations, have been described as manifestations of culture.”
Many things remain unknown about this species, The IUCN reported in 2008, “The taxonomy of this genus is clearly in need of review, and it is likely that O. orca will be split into a number of different species or at least subspecies over the next few years.“
If you read the Wikipedia page, you'll see that the Killer Whale in the picture is hard to categorize. It looks like type B but the saddle patch doesn't fit.
The yellowish coloring of the pictured individual is probably due to alguaes.