The Farmer Goes to Sea

Michael Weber groans when he hears this kind of talk. â€We´ve seen this movie before,†insists the former special assistant to the director of the National Marine Fisheries Service. â€And it doesn´t end nicely.†He cautions that our history is filled with grand schemes for fishing, backed by the government and focused solely on increasing production. People thought any problems or miscalculations would be swallowed up by the vastness of the sea.

â€So much of the boosterism around aquaculture today reminds me of the 1960s,†Weber says. â€Scientists back then believed that we could take 500 million metric tons a year from the ocean, so that´s how our fisheries were managed.†But the ocean could afford to give up only about 20 percent of that figure. â€We´re living with the consequences of that error today,†he observes, in crashed fisheries and the economically shattered communities left in their wake. And even if the increased volume of seawater does take care of nutrient pollution (a few studies suggest that that may be the case, but the issue is far from settled), Weber charges that OOA does nothing to address some of aquaculture´s other problems, such as the spread of disease from farmed to wild fish and â€gene pollution†from escapees interbreeding with local populations.

Cates has anticipated these objections. Disease is unlikely to be a problem for him, he says, because of the cleansing effect of the strong ocean currents off Oahu-and because his cages aren´t overpacked or crowded into one area (conditions likely to lead to an outbreak). Since he raises moi, a local fish, gene pollution isn´t a concern either. If you spend any time with Cates, it´s easy to see him as a poster boy for OOA, creating a financially successful business that´s sensitive to the environment. But that´s exactly the problem, maintains Michael Hirshfield, chief scientist with the nonprofit advocacy group Oceana: â€Not everybody is a Randy Cates. That´s why we need strong regulations-to require all OOA operators to be diligent about taking care of the environment.â€

Despite these concerns, it´s clear that OOA is moving ahead. A barge carrying 20 tons of fish pellets recently made its maiden voyage out to Cates´s moi cages. Once it´s moored in place, with feeding lines attached, the barge doesn´t require a human presence. From his office on shore, Cates uses his PC to tell the barge´s computer to release the right amount of food at the right time. Cates can even monitor the operation with images beamed from cameras mounted on the barge and in the cages themselves.

Others are leaping even farther ahead, at least conceptually. Cliff Goudey, who directs the Center for Fisheries Engineering Research at the Massachusetts Institute of Technology, sees OOA´s move from shallow-water anchorage to deep-water anchorage as a good first step. The next step is to let go of the anchor. â€Once you free yourself from a mooring,†he explains, â€all of a sudden you realize you´re no longer at the mercy of all that nature throws at you. You use the ocean currents, rather than resist them.â€

Goudey has worked for years on Ocean Drifter, an untethered fish cage with a diameter three times as large as the SeaStation´s and remote-controlled thrusters to maneuver within ocean currents. Goudey 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.

For now, the largest Ocean Drifter is an 18-foot-diameter prototype whose greatest journey was inside the Navy´s David Taylor Model Basin in Bethesda, Maryland. â€It´s not quite ready for prime time,†Goudey admits. But, he hastens to add, OOA â€is the only way to meet future demand for seafood. And the Ocean Drifter, or something like it, is the future of open-ocean aquaculture.â€

The past is often the best crystal ball in which to catch glimpses of the future. With this in mind, while in Hawaii, I take a day trip to a fish pond that is said to be 1,000 years old. He´eia Pond is just 14 miles from Cates´s moi cages, over the Koolau mountains on Oahu´s windward side. The first Hawaiians began building fish ponds 2,000 years ago, not long after arriving from the Marquesa Islands. In 1778, when the British explorer Captain James Cook arrived in Hawaii, he found some 360 fish ponds producing nearly two million pounds of seafood. The ponds are great feats of engineering, a happy marriage of marine biology and technological skill. They are shallow, to provide the optimal amount of sunlight to grow algae for young fish to eat. And they have sluice gates-slots large enough to allow young fish in but small enough to trap them when they´ve grown, as well as to keep predators out. Behind the sluice gates are solid gates. The combination allowed workers to clean the pond by trapping water at high tide and releasing it when the tide ran out. Nearly a mile around, the 88-acre He´eia Pond is a model for sustainable aquaculture.

â€Yeah, there´s a lot to the â€old school´ ways,†says Will Ho´o´pi´i, a native Hawaiian who´s out walking his dogs when I drive up. â€They raised moi in there,†he says as we look down on He´eia Pond. I ask if he´s heard about the underwater cages, where 100,000 moi swim in what some think is the future of the seafood industry. No, he hadn´t heard about them, but the idea makes him smile. â€It could be the future, you know,†he says, â€if they do it the way the old people did.â€

How was that? I ask. He looks at me for a moment as if it´s obvious. Then he gestures toward the ancient pond. â€Carefully,†he says. â€Very carefully.â€

To find out where you buy OOA fish, see popsci.com/fishfarming.

Osha Gray Davidson is the author of Fire in the Turtle House (Public Affairs). This is his first article for Popular Science.