Baleen whales eat plankton and krill, not game fish. These are the targets of Japanese whalers. To give you some perspective, a blue whale would choke on an orange, or so I've read.
Toothed whales, ie the Sperm, Killer whale, and the beluga, on down to the dolphin, are the exception.
Sperm whales eat giant squid almost exclusively.
Killer whales eat whatever they want, up to and including the great baleen whales like the Blue.
The smaller toother whales eat small game fish. None of the toothed whales are hunted in any number nowadays, except maybe the Sperm, I'm not really sure. It got it's name from the high quality oil harvested from them, used for machine lubrication and in lamps. It resembles (gasp!) semen, hence the name.
The Japanese are full of shit on this one. Check the school texts on WWII for more laughs.
HEHE, I said "sperm," Three times and semen once!