This was news to me, but in the other direction: the claim is that 50-60 percent of fish served as sushi has been frozen at some point, implying that 40-50 has

This was news to me, but in the other direction: the claim is that 50-60 percent of fish served as sushi has been frozen at some point, implying that 40-50 has never been frozen. Given that most of the non-tuna species need to be frozen and the tuna supply chain consists almost entirely of frozen fish outside of some high end restaurants in big cities (and perhaps some fishing towns that make a up vanishingly small portion of sushi consumption) - where is all this fresh fish coming from? On top of that, salmon and varieties of tuna seem to make up the large majority of fish used in sushi. Yes, other options exist, especially at high-end places, but go into your run-of-the-mill sushi joint pretty much anywhere and those two dominate (not counting the "fake crab" that seems to make up half of maki by weight these days - that's certainly frozen also). As above, tuna is generally frozen, and salmon largely has to be, so where is all this fresh fish at?