Sayonara, Sushi?

(CBS)  For Americans to understand this Japanese crisis, imagine bluefin tuna is a steer - and succulent sushi like a juicy steak. Now, imagine your country's favorite food was about to go the way of the dinosaurs.

That's the future facing Japan.

Bluefin tuna, the centerpiece of Japanese sushi, is being loved to extinction bite by bite.

Ellen Pitkitch, from the Pew Institute for Ocean Science, said: "We really have a chance of totally losing this fish."

Pikitch, a fishery researcher, said international fishing quotas enacted to protect the bluefin are too weak and hard to enforce.

To get an idea of the magnitude of this problem, look no further than right here - Tsukiji - Tokyo's central fish market, the size of 40 football field where they trade 3,000 whole tuna every day.

Flash frozen at sea, truckloads of bluefin tuna are unloaded, displayed and inspected. Then comes the auction.

While it might look bountiful to us, to merchants like Narihiko Kimura, who's worked here for ten years, it is one-third what it was in the past he says. And the price - it's been going up drastically. Some of these tuna sell for $14,000 or more and there's plenty of blame to go around.

Gone are the days when Japan had sushi to itself. Raw fish has gone global. Americans have a taste for it. Europeans and Chinese, too.

So while Japan ponders a bluefin tuna-less future, how about this hearty American sushi substitute? Hamburger sushi anyone?