End of the Line:
Can Fish Farming take the place of catching
them?
http://www.time.com/time/health/article/0,8599,2081796-1,00.htmlFish
are the last wild food, but our oceans are being picked clean. Can farming
fish take the place of catching them?
Josh Goldman
runs a fish farm, but the hangar-size facility in the western Massachusetts
town of Turners Falls looks a lot less like a farm than a factory. Thousands
of one-third-pound barramundi — an omnivorous fish native to Southeast Asia
and Australia — swim in a 36-ft.-diameter tank that resembles a supersize
kiddie pool. They spend their days fattening up on feed pellets under the
watchful eyes of factory workers — farmers, if you must — who grade them for
size. After several weeks of careful feeding, the fish are moved via an
industrial waterslide — the pescalator, Goldman calls it — to a larger tank in
the plant's next cavernous room. The assembly line runs until the barramundi
have been raised to market weight, about 2 lb., after which they're sent off
to white-tablecloth seafood restaurants and sustainability-minded retail
outlets across the U.S.
From the moment the barramundi are hatched,
from eggs barely one-hundredth of an inch long to the day they're sold, they
never swim in a river or sea, never hunt for food, never feel the tug of a
fishing line. "We're producing great-quality fish without harming the oceans
or anything else," Goldman says of his operation, Australis Aquaculture. His
barramundi aren't caught; they're manufactured. And factories like these might
represent the last, best chance for fish to have a future.
Since human
beings first took up the plow about 10,000 years ago, most of our food has
come from the farmer's hand. We grew fruits, vegetables and grains to feed
ourselves and support those domesticated animals we relied on for meat and
dairy products. But there was an exception. When humans fished, we still went
out into the wild, braved the elements and brought back decidedly
undomesticated animals for dinner. There was a romance to fishing that was
inseparable from the romance of the sea, a way of life — for all its peril and
terror — suffused with a freedom that the farmer and rancher would never know.
Though the fishermen who roved the Sea of Galilee in Jesus' time and the
factory trawlers that scrape the ocean floor today couldn't be more different,
they share a common link to our hunter-gatherer past. "Fish are the last wild
food," says Paul Greenberg, author of Four Fish, one of the best books on the
state of seafood. "And we're just realizing it."
But we may be coming
to that realization too late, because it turns out that even the fathomless
depths of the oceans have limits. The U.N. reports that 32% of global fish
stocks are overexploited or depleted and as much as 90% of large species like
tuna and marlin have been fished out in the past half-century. Once-plentiful
species like Atlantic cod have been fished to near oblivion, and delicacies
like bluefin tuna are on an arc toward extinction. A recent report by the
International Programme on the State of the Ocean found that the world's
marine species faced threats "unprecedented in human history" — and
overfishing is part of the problem.
Meanwhile, the worldwide catch
seems to have plateaued at about 90 million tons a year since the mid-1990s.
That's a lot of fish, but even if those levels prove sustainable, it's not
enough to keep up with global seafood consumption, which has risen from 22 lb.
per person per year in the 1960s to nearly 38 lb. today. With hundreds of
millions of people joining the middle class in the developing world and fish
increasingly seen as a tasty and heart-healthy form of protein, that trend
will continue. The inescapable conclusion: there just isn't enough seafood in
the seas. "The wild stocks are not going to keep up," says Stephen Hall,
director general of the WorldFish Center. "Something else has to fill that
gap."
Something else already does: aquaculture. Humans have been
raising some fish in farms for almost as long as we've been fishing, beginning
with Chinese fishponds 4,000 years ago. But it's only in the past 50 years
that aquaculture has become a true industry. Global aquacultural production
increased from less than 1 million tons in 1950 to 52.5 million tons in 2008,
and over the past few decades, aquaculture has grown faster than any other
form of food production. Today about half the seafood consumed around the
world comes from farms, and with the projected rise in global seafood
consumption, that proportion will surely increase. Without aquaculture, the
pressure to overfish the oceans would be even greater. "It's no longer a
question about whether aquaculture is something we should or shouldn't
embrace," says Ned Daly, senior projects adviser at the Seafood Choices
Alliance. "It's here. The question is how we'll do it."
That's not an
easy question to answer, because the rapid growth of aquaculture has been
accompanied by environmental costs. In the past, the dense salmon farms of
Canada and northern Europe helped spread disease among wild fish while
releasing waste into coastal waters. Mangrove forests, which provide a
valuable habitat for coastal life, have been razed to make way for Thailand's
shrimp farms. Especially troubling, many of the most popular farmed species
are carnivores, meaning they need to be fed at least partly with other fish.
By one count, about 2 lb. of wild fish ground up to make fish meal is needed
on average to produce 1 lb. of farmed fish, which leaves the ocean at a net
loss. "Aquaculture's reliance on fish meal and fish oil is a major concern for
marine conservation," says Sebastian Troeng, a marine expert with Conservation
International.
But unless you can convince 1.3 billion Chinese — not to
mention everyone else in a growing world — that they don't deserve the
occasional sushi roll, aquaculture will keep growing. As it does, it will need
to become more efficient and less polluting. The good news is that the
industry is improving. More farmable but less familiar species like the
barramundi — which yields more protein than it takes in as feed — may have to
supplement popular fish like cod that haven't taken as well to aquaculture. We
may even need to genetically engineer popular species to make them grow faster
and bigger. And perhaps most of all, we need to accept that on a planet with a
population of nearly 7 billion and climbing, we may no longer be able to
indulge our taste for the last wild food. We've farmed the land. Now we have
little choice but to farm the sea as well.
Aquaculture and Its
Discontents
To the average shopper, farmed fish is barely distinguishable
from its wild cousin — except, often, in price. Without the growth in
aquaculture, many of our favorite kinds of seafood would likely be much more
expensive than they are now. And chances are, you get what you paid for:
farmed seafood can be inferior to wild fish in taste and may not always have
the same nutritional value. Salmon raised in an aquaculture environment, for
instance, often have lower levels of cardiovascular-friendly omega-3s than
wild fish, and farmed fillets would actually be gray without a pink chemical
dye. And if you're eating farmed seafood, you're almost certainly getting it
from overseas: U.S. aquaculture accounts for just 5% of Americans' seafood
consumption. The Monterey Bay Aquarium's Seafood Watch program mostly
discourages consumers from choosing farmed fish, both for health reasons and
because of worries over the environmental impact of aquaculture. "There's a
real difference in the regulation you might see in other countries compared
with the U.S.," says Peter Bridson, Monterey's aquaculture-research
manager.
At the same time, it's important to look at the big picture.
For health reasons, most of us should be eating more fish. For its new dietary
guidelines, the U.S. government just upped the recommended consumption of
seafood to 8 oz. or more a week — which is more than twice what the average
American eats — and 12 oz. for pregnant women. In a report this month, the
U.N. said global food production would need to increase by as much as 100% by
2050 to meet growing demand — and seafood, as a vital protein source, will
have to be part of that. Farming is unavoidable. "There may be a price split
between expensive wild fish and cheaper farmed fish," says Don Perkins, head
of the Gulf of Maine Research Institute. "But seafood consumption will spread
because we need it for health reasons."
To understand global
aquaculture — its potential and its problems — it helps to look at the
industry's track record in China, a country responsible for 61% of the world's
aquaculture. China has begun exporting industrially produced catfish, shrimp
and tilapia in recent years. As production pressures have ramped up, Chinese
manufacturers have packed their ponds more tightly, leading to disease and
pollution from fish waste. That waste can overload coastal waters with
nutrients, causing dead zones that can strangle sea life. To fight the
diseases worsened by crowding, Chinese fish farmers have liberally used
antibiotics and other drugs, including malachite green, an antifungal agent
and potential carcinogen that was banned by Beijing in 2002 but shows up
periodically in exports. "It is still a problem," says Wong Ming Hung, a
biology professor at Hong Kong Baptist University.
While China remains
a laggard on safety — though experts say its fish-farming industry is
improving as it matures — there's no denying that aquaculture can be messy. A
badly run near-shore farm of 200,000 salmon can flush nitrogen and phosphorus
into the water at levels equal to the sewage from a town of 20,000 people. But
for all that, fish farming's bad reputation isn't entirely deserved,
especially if it's compared with farming on land.
chanics and
metabolism. Unlike land animals raised for food, fish are cold-blooded and
live in the water, which means less of their feed is wasted — from our point
of view — being burned as energy to keep warm or to build bone. Fish farmers
had the bad luck to come along after industrial meat production was well
established, and the new guy on the block gets more scrutiny. "We have to
address the environmental and social issues," says Jose Villalon, director of
the WWF's aquaculture program. "But aquaculture is a good tool to deal with
food security."
One way to address those issues is to build an
aquacultural system that mimics nature, in which the waste produced by farmed
fish is put to use. Thierry Chopin, a biologist at the University of New
Brunswick, wants to take advantage of that principle with his integrated
multitrophic aquaculture (IMTA). In an IMTA loop, species like salmon and
shrimp are raised less densely than in conventional aquaculture, together with
seaweed and shellfish like mussels. The waste from the farmed species
fertilizes the seaweed, which can be harvested for use in fish feed. The
mussels, which are filter feeders, can gobble waste in the water, preventing
pollution from building up. The result is more biomass and less waste — just
as nature intended. "If it functions as an ecosystem does," says Chopin, "then
it functions right."
Even an aquacultural system more in tune with
nature still faces essential challenges, including the feed-ratio problem.
When producers began raising fish intensively, they picked species that people
like to eat: salmon and sea bass. But those species are high on the food
chain, and raising them on a farm is a bit like trying to domesticate tigers.
The aquaculture industry has gotten better at replacing fish meal with
plant-based feed, but not fast enough. You're not feeding the world
sustainably if you need to remove the base of the marine food chain to do it.
"The question of what the fish will eat is central to aquaculture," says
Australis' Goldman. "We can't grow on the back of small forage
fish."
A Fish and a Dream
The answer might be simply to find a
better fish, one more suited to farming. This is exactly what Goldman set out
to do. He got into aquaculture in the 1980s as a college student and had a
tilapia-farming operation for a few years. But while tilapia are more
sustainable than many other fish because they're vegetarians, they lack the
high amounts of omega-3 oils that make salmon so heart-healthy. Goldman tried
striped bass but found them too fussy to raise. It wasn't until a chance
encounter with an Australian entrepreneur that he found his dream fish: the
barramundi.
As a farmed species, the barramundi is just about perfect.
It can survive in a wide variety of environments and lays eggs frequently. It
has a flexible diet, and much like its fellow Australians, it is laid-back by
nature, so it can endure the rigors of farming. Goldman launched Australis in
Turners Falls in 2004 and was producing barramundi commercially by 2005. The
fish is rich in omega-3 oils; Dr. Oz named it one of his top superfoods in
2010. Less than 20% of the barramundi's feed at Australis comes from fish meal
and fish oil — a better percentage than for many farmed salmon, which can
require as much as 50% of their feed from fish meal. The Turners Falls
operation is an indoor, closed recirculating system, so there's little waste,
little risk of disease and no threat that the barramundi will escape into the
wild. Plus, barramundi tastes good, with the flaky mouthfeel of the
better-known sea bass. Goldman's real challenge is convincing Americans — with
their appetite for shrimp, tuna and salmon — that they should eat an
unfamiliar Australian fish. "Selling it as sustainable helps," he says. "But
once they try it, people like it."
Australis' barramundi has become so
popular, in fact, that Goldman has expanded production — but not in
Massachusetts. While the closed recirculating system he uses in Turners Falls
is an environmentalist's dream, Goldman eventually wanted to reach a larger
market at a lower cost, a step that he decided required an outdoor operation
on the central coast of Vietnam. That branch, where barramundi are raised in
sea cages in a protected bay, isn't quite as green as Turners Falls, but it's
cheaper.
Land-based systems may work for more premium species, and they
offer the chance to raise fish close to cities. In New York State, for
instance, a company called Local Ocean produces indoor-farmed sea bass and
flounder two hours from Manhattan. But such systems are still more
experimental than economical. "As much as the NGOs would have loved it,
[Australis] just couldn't meet the economics of an expensive indoor
environment," says Goldman.
Rise of the Frankenfish
Many NGOs would
also like us all to choose farmed fish more judiciously, selecting sustainable
species low on the food chain. There's not a lot of evidence that's going to
happen, however. But if we won't always choose the fish that take better to
farming, another option is to take the fish we like and engineer them into
sustainability. Fish farmers have been doing that quite naturally for the past
few years, breeding salmon and other species so they grow faster and require
less fish meal — something farmers on land have done for hundreds of years
with cattle, pigs and chicken. The Massachusetts-based biotech company
AquaBounty wants to take that breeding process a step further by genetically
engineering Atlantic salmon that can grow up to twice as fast as conventional
fish. Its product, the AquAdvantage salmon, contains a gene from the chinook
salmon, a larger cousin that lives in cold northern waters. That gene
activates a growth hormone, with obvious commercial benefits for farmers who
want to get their fish to market weight quickly. "America imports its seafood
at the cost of a huge carbon footprint," says Ronald Stotish, AquaBounty's
CEO. "This could make it economical to raise land-based salmon domestically.
This is sustainability."
The Food and Drug Administration convened
a panel of experts last fall to review the genetically modified (GM) salmon,
and they were mostly satisfied with AquaBounty's proposal. But while the FDA
hasn't yet decided whether to approve what would be the first genetically
modified food animal, most environmental groups are staunchly against what
they've termed the Frankenfish. They worry about the possible effect on human
health, and they're concerned that if GM salmon escape into the wild — as
conventionally farmed salmon do all the time — they might outcompete wild
salmon.
While AquaBounty has pledged to ensure that the GM salmon will
be kept sterile and produced in confinement, critics fear that something will
go wrong. (As a government scientist wrote in a leaked e-mail, "Maybe [the
FDA] should watch Jurassic Park.") "Absence of evidence does not mean evidence
of absence," says Zach Corrigan, fish-program director for Food & Water
Watch. "The regulation isn't there."
Even if GM salmon doesn't
succeed in North America, it might find a home in China or another fish-hungry
country where knee-jerk resistance to transgenic technology isn't so strong.
And newer, better GM fish are being engineered in labs right now, including a
transgenic trout that can pack on 15% to 20% more muscle than a conventional
fish. But the very fact that we can ponder these issues shows how much our
relationship with the last wild food has changed. For thousands of years,
fishermen risked the elements to bring back the bounty of the sea. Fishing is
the deadliest job in the U.S.: in 2009, 0.2% of fishermen died hauling in our
seafood, compared with 0.01% of miners who died on the job. But that danger is
also part of the allure, as the success of TV shows like The Deadliest Catch
and books like The Perfect Storm demonstrates. "Fishermen are the last
commercial hunters in the world," says Sebastian Belle, director of the Maine
Aquaculture Association, who has seen unemployed New England fishermen take up
aquaculture. "They had the excitement of never knowing what they were going to
get."
With 7 billion people, however, the planet doesn't have much
space for such freedom. It's not that commercial fishing will disappear; in
fact, sustainable fisheries like Alaska's wild-salmon industry may even
produce boutique foods, finally earning what they're worth. There's no doubt
that something will be lost in the transition to mass aquaculture, as fish —
the last true wild food — are domesticated to support human beings, in much
the same way we tamed cattle, pigs and chickens thousands of years ago. But if
we're all going to survive and thrive in a crowded world, we'll need to
cultivate the seas just as we do the land. If we do it right, aquaculture can
be one more step toward saving ourselves. And if we do it well, we may even
enjoy the taste of it.
— With reporting by Austin Ramzy / Beijing and
Robert Horn /
Bangkok