A Green Venture — Tuna In A Tank - Decline of the Empire

Few stories better capture the human relationship with the natural world than Science Daily's Developing Techniques for Tuna Aquaculture (June 12, 2013).

Swimming around and around in a 20,000 gallon tank at the University of Rhode Island's Bay Campus are several large yellowfin tuna captured last fall about 100 miles off the Rhode Island coast. The fish are part of the first effort in the United States to breed tuna in a land-based aquaculture facility to meet the growing demand for one of the ocean's top predators.

"Worldwide demand for tuna increases yearly, even as tuna stocks are dwindling precipitously," said Terry Bradley, a URI professor of fisheries and aquaculture. "What we're trying to do is produce fish in captivity and take the pressure off the wild stocks."

Bradley and Peter Mottur, director of Rhode Island-based Greenfins, are taking the first steps in developing the techniques to raise tuna from egg to harvest size while creating a new sustainable industry in Rhode Island.

According to Bradley, some in Australia, Mexico and several Mediterranean countries are doing what he calls "tuna ranching" by capturing wild tuna, putting them in pens and raising them to harvest size.

"All they're doing is taking wild fish and fattening them up," he said. "It's still depleting the wild population and has had a long-term impact on tuna stocks."

Endangered bluefin and yellowfin tuna are large predators which range far and wide in the world's oceans. A 20,000 gallon tank?

Bradley and Mottur are starting the process by trying to get a few wild-caught tuna to spawn in the URI tank, but it is a challenging undertaking. Tuna are long-distance migrants that swim at great speeds, so acclimating them to a 20-foot diameter tank has been difficult. Once the fish spawn and the eggs hatch, the microscopic larvae must be fed live food raised on site. Then they must be weaned from live food to a dry, formulated feed.

Bradley and Mottur believe that construction of a larger tank, which will be built at the URI Bay Campus later this year, will markedly increase the project's likelihood of success.

"Tuna are open ocean fish that require a lot of space and need very good water quality," Bradley said. "If you put too many fish in a tank, they get stressed and the water quality begins to degrade. The less you stress them, the more likely they are to spawn in a reasonable time frame."

Yes, that's the ticket—build a larger tank! How big should that tank be? I think something the size of Rhode Island itself would do very nicely

Let us move beyond the absurdity of raising tuna in a tank. How does this project reflect the human relationship with the natural world?

♦ What is the best way to "take pressure off wild stocks" of tuna?

That's an easy one—humans need to stop catching tuna in all the world's oceans right now. But banning tuna fishing is impossible for humans to achieve. Thus the obvious behavioral change required to save these magnificent animals is off the table.

♦ What will humans do instead?

Well, what do humans always do? Start a business! Make some money!

According to Bradley and Mottur, it's the ideal time for a tuna aquaculture venture.

"Japan can't produce all the tuna it needs for the country's own purposes, and the U.S. is a net importer of fish, including tuna," Bradley said. "So there is tremendous potential for us to produce fish that could easily be sold in the U.S., especially if it's a sustainable product in an environmentally responsible manner."

It's an ideal time for tuna aquaculture because the world's tuna stocks are declining precipitously. Clearly this project is going to be a money-maker, both before and after the wild tuna are gone.

♦ Aside from being profitable, what kind of business will it be?

That's an easy one too—it will be a green, environmentally friendly, sustainable business. It's not called "Greenfins" for nothing. This project is so god-damned green that it will be sustainable long after the wild tuna have been killed off, assuming—you guessed it!—the right technology can be brought to bear.

The early stages of the project are all about research — learning about the early life cycle of these fish and developing the techniques to raise them," Bradley said.

"But we also think there is a lot of commercial potential."

Bradley and Mottur envision local entrepreneurs using the techniques they develop to produce juvenile tuna that could then be sold to others who want to grow them further. In Japan, an eight-inch juvenile tuna raised in captivity can be sold for $100 to $125.

"It's a sustainable project that we hope will create green technology jobs here in Rhode Island to leverage the great intellectual capital we have in the state," said Mottur.

You can't have a green business using green technology unless you promise to create green jobs too.

♦ Will this new green venture actually alleviate the pressure on wild tuna stocks in the world's oceans?

No. Hell, no. To take pressure off wild tuna populations, there would have to be a fixed level of demand for these tasty fish. If you raise captive tuna and then sell them to others who will "fatten them up," you will likely lower the price for all kinds of tuna because nobody cares where their tuna comes from, and thus you will likely increase the demand for all kinds of tuna, including wild yellowfins and bluefins. If there weren't great latent demand for tuna, wild tuna species wouldn't be traveling down the unhappy road toward commercial, if not total, extinction.

See my older posts The International Conspiracy To Catch All Tuna (June, 2011), and There Go The Pacific Bluefins (January, 2013).

Thus we see in this seemingly innocuous tuna breeding story all the elements which define the perverse human relationship with the natural world. The details vary from story to story but in the end it is always the same story—the manipulation, appropriation and obliteration of Nature to further human purposes.

I don't have to tell you that this story will not end well.