Inside this underwater cage, some 100,000 silvery fishes swim around a central steel column. “They are adolescent moi,” we are told, “also known as Pacific threadfin or Polydactylus sexfilis. For the first 50 days of life, the moi are raised on land, in a series of progressively larger tanks—from fertilized eggs smaller than grains of salt to two-inch fingerlings. The young fish are taken by boat to the submerged cage and pumped into it through a long tube. The moi swarming around the spar now each weigh half a pound. But in a few months they’ll have doubled or tripled in size. At that point, the moi will be harvested and sold at fish markets and to top restaurants across Hawaii, where they are a much-coveted delicacy.”
And outside the cage, “[s]everal sandbar sharks circle the cage, their hungry eyes fastened on the fish of kings.”
While the prototype mentioned above is tethered to the ocean floor, there are plans for an untethered version with “remote-controlled thrusters to maneuver within ocean currents.”
Cliff Goudey, who directs the Center for Fisheries Engineering Research at MIT, “envisions a flotilla of Ocean Drifters, each filled with hundreds of thousands of fingerlings in Florida and set loose in the Gulf Stream. The warm Caribbean current is like a river within the sea, carrying the cages across the North Atlantic and delivering the by-then-grown fish to markets in Europe.”
If open-ocean aquaculture turns out to be a bust, however, you could always turn them into a tourist attraction — mobile aquariums in a continuous transoceanic loop around the world, perpetually migratory, each one housing a swirling vortex of self-organizing non-Euclidean topology.
And if you get hungry...
Aquapod®