According to this New York Times article, we are on the verge of a revolution in aquaculture that may lead to the domestication of the ocean:

"Taking a long-range view, there is little doubt that we are on the verge of a vast new artificial selection that will determine the characteristics of a future marine ecology. As recently as 20 years ago, aquacultured products were niche items — the bright red slab of lox from Norway, the crawdad from Louisiana. Today, dozens of mainstream fish are being domesticated and will soon appear at supermarket counters everywhere. Yellowtail, halibut, red snapper and even Volkswagen-size bluefin tuna are all coming under some kind of human-controlled production. And whereas animals like sheep and cattle were adapted to fit the farm over thousands of years, many of the ocean species under development today could be tamed in as little as a decade."