Seafood supplies are dwindling. Fish farming presents its own problems. An expert offers his game plan for a sustainable, delicious future.
As someone who catches, cooks, and eats a lot of fish, I’m often asked whether this is still morally acceptable. For the past decade, a growing chorus of environmental activists and scientists has increasingly voiced the idea that seafood faces a dire crisis. A controversial and highly publicized 2003 paper in the journal Nature speculated that 90 percent of the world’s big fish are already gone—the result of an exponential increase in fish catching from 1950-1999. A later Science paper suggested we will have no more wild fish to eat by 2048 if oceanic biodiversity continues to dwindle.
On the farmed side, prospects seem equally bleak. Stanford economist Rosamond Naylor published a study in 2000 revealing that more than three pounds of wild fish may be required as feed to produce one pound of farmed salmon. Add to this numerous reports of disease, ecosystem-killing pollution, and farmed-fish escape, and fish farming comes off not as a salve but as an accelerator of wild fisheries’ collapse.
All this begs the question: Should we just stop eating fish?
I may be biased, but I say no. I would argue that humans’ dependence on consuming fish is the one thing that will compel us to preserve them. Beneath our seas sit some of the world's largest deposits of oil, coal, natural gas, and precious metals. But as the recent oil spill in the Gulf of Mexico showed, extracting that wealth can come at a huge environmental cost. And while there are many bleeding hearts who think the sight of oiled pelicans and petroleum-fouled dolphins is enough to make us change our ways, humans are essentially selfish. What really will prevent us from ruining the oceans is recognizing bad environmental behavior as a threat to our food supply. Our hearts are curiously close to our stomachs. All things considered, maintaining the oceans as a food system is the fish’s best defense against our seas becoming poorly managed oil- and mineral-extraction systems.
So what’s the game plan? How do we continue to catch wild fish without catching them all? And how do we farm fish without destroying the fish we’re trying to supplement by farming in the first place?
Those who catch wild fish must reimagine themselves not as hunter-gatherers but as herder-stewards. Since civilization’s dawn humans have tended to hunt wild animals as if their populations were limitless. One need only look at Paleolithic kill sites—where our ancestors drove herds of game off cliffs—to see that over-harvesting goes back a long way. But we are not cavemen! Today we have functional models for estimating how many fish we can kill before populations go into irrevocable decline. If we can transfer a sensitivity to rational limits directly to those who fish, there is hope.
This process is already working with a handful of fish, like Gulf red snapper. After lengthy overexploitation of these vermilion beauties, red snapper fishing was converted to a “catch-share” system whereby fishermen are allotted their share of fish before they catch them. In earlier days managers would announce a season opening date and fishermen would race to catch as many fish as they could before the season closed, often overfishing their stock in the process. With a catch-share system you can only catch what you have already been allotted, and what you have been allotted is precalculated to jibe with proven ecological limits. In a catch-share system, a fisherman is intimately connected to his stock of fish, just as a herder is connected to his flock. A fisherman must protect his share year in and year out if he is to have a stable market. Similar fishery conversions have worked to great effect in protecting Alaska halibut. Even the famously destroyed codfish grounds of New England are rebuilding that historic fishery in part by embracing catch-shares.
With farmed fish, the challenge is figuring out how to grow more fish without destroying the natural world that produces them. The historical model of clear-cutting forest or burning prairie to create farms cannot become the model for aquaculture (the fastest-growing form of food production on earth, incidentally).
Achieving an aquaculture sector that is in sync with rather than opposed to the natural environment will require two radical shifts. First, we must figure out something to feed farmed fish besides . . . other fish. There are several viable alternatives. One company, Oberon FMR of Idaho Springs, Colo., has developed a way to produce feed-grade protein from brewery beer-sludge. It’s this kind of thinking that needs to underpin all forms of food production.
Aquaculture also needs to move beyond the idea of the one-crop farm—for example, just salmon—often a great detriment to the environment. As we have seen with corn, soy, and even beef feedlots, single-crop farms or ranches produce huge quantities of waste and become progressively less productive. There is no reason for fish farming to replicate these mistakes. Already, functional polycultures of fish are being launched, like Cooke Aquaculture’s pilot program on the Bay of Fundy in Canada. There, Dr. Thierry Chopin is leading a trial of integrated multi-trophic aquaculture in which mussels, edible seaweeds, and sea cucumbers are grown in conjunction with salmon. Chopin is trying to create a more efficient system with multiple crops radiating out from a single feed source. Because mussels, sea cucumbers, and seaweed can all absorb nutrients from salmon waste, they have the potential to neutralize and reuse the effluent that has plagued salmon farms in the past.
The final piece in the puzzle is getting consumers to choose these more positive options for both wild and farmed seafood. Once again, there is cause for optimism. From the first modest attempts to differentiate good seafood from bad in the late 1990s, seafood ratings programs have blossomed and are using the same scientific data to make similar recommendations, helping to provide greater consistency across markets. A key resource in this regard is Seafood Watch, a program of the Monterey Bay Aquarium, which can be downloaded to an iPhone or Android-compatible device or viewed online at montereybayaquarium.org/seafoodwatch . If you are without smartphone or computer but have a cell phone, you can text 30644 with the message FISH and the name of the fish in question; the highly regarded nonprofit Blue Ocean Institute will message you back with information. And if you want to dine out on seafood you can visit fish2fork.com , a site that rates restaurants based on their seafood sourcing practices.
So let’s continue to eat fish, enjoy and celebrate them in their wild form, harvest them sensibly, and turn those who catch them into guardians of the deep. At the same time, let’s proceed with fish farming, but leapfrog over the bad behavior we learned in land-based animal husbandry. Let’s eat from the sea and at the same time strike a balance with it.
This article was first published in December 2011. Some facts may have aged gracelessly. Please call ahead to verify information.