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By
Kenneth R. Weiss
Like cattle pens,
the salmon operations bring product to market cheaply. But
harm to ocean life and possibly human health has experts worried.
If you bought a
salmon filet in the supermarket recently or ordered one in
a restaurant, chances are it was born in a plastic tray here,
or in a place just like it.
Instead of streaking
through the ocean or leaping up rocky streams, it spent three
years like a marine couch potato, circling lazily in pens,
fattening up on pellets of salmon chow.
It was vaccinated
as a small fry to survive the diseases that race through these
oceanic feedlots, acres of net-covered pens tethered offshore.
It was likely dosed with antibiotics to ward off infection
or fed pesticides to shed a beard of bloodsucking sea lice.
For
that rich, pink hue, the fish was given a steady diet of synthetic
pigment. Without it, the flesh of these caged salmon would
be an unappetizing, pale gray.
While many chefs
and seafood lovers snub the feedlot variety as inferior to
wild salmon, fish farming is booming. What was once a seasonal
delicacy now is sometimes as cheap as chicken and available
year-round. Now, the hidden costs of mass-producing these
once wild fish are coming into focus.
Begun in Norway
in the late 1960s, salmon farming has spread rapidly to cold-water
inlets around the globe. Ninety-one salmon farms now operate
in British Columbian waters. The number is expected to reach
200 or more in the next decade.
Industrial
fish farming raises many of the same concerns about chemicals
and pollutants that are associated with feedlot cattle and
factory chicken farms. So
far, however, government scientists worry less about the effects
of antibiotics, pesticides and artificial dyes on human health
than they do about damage to the marine environment.
"They're like
floating pig farms," said Daniel Pauly, professor of
fisheries at the University of British Columbia in Vancouver.
"They consume a tremendous amount of highly concentrated
protein pellets and they make a terrific mess."
Fish wastes and
uneaten feed smother the sea floor beneath these farms, generating
bacteria that consume oxygen vital to shellfish and other
bottom-dwelling sea creatures.
Disease and parasites,
which would normally exist in relatively low levels in fish
scattered around the oceans, can run rampant in densely packed
fish farms.
Pesticides fed
to the fish and toxic copper sulfate used to keep nets free
of algae are building up in sea-floor sediments. Antibiotics
have created resistant strains of disease that infect both
wild and domesticated fish.
Clouds of sea lice,
incubated by captive fish on farms, swarm wild salmon as they
swim past on their migration to the ocean.
Of all the concerns,
the biggest turns out to be a problem fish farms were supposed
to help alleviate: the depletion of marine life from over-fishing.
These fish farms
contribute to the problem because the captive salmon must
be fed. Salmon are carnivores and, unlike vegetarian catfish
that are fed grain on farms, they need to eat fish to bulk
up fast and remain healthy.
It takes about
2.4 pounds of wild fish to produce one pound of farmed salmon,
according to Rosamond L. Naylor, an agricultural economist
at Stanford's Center for Environmental Science and Policy.
That means grinding
up a lot of sardines, anchovies, mackerel, herring and other
fish to produce the oil and meal compressed into pellets of
salmon chow.
"We are not
taking strain off wild fisheries. We are adding to it,"
Naylor said. "This cannot be sustained forever."
In British Columbia,
the industry, under pressure from environmentalists, marine
scientists and local newspapers, is taking steps to mitigate
some of the ecological problems.
"We have made
some mistakes in the past and we acknowledge them," said
Mary Ellen Walling, executive director of the British Columbia
Salmon Farmers Assn. "We feel the industry is sustainable,
if well-managed, and we have a code of practices that is followed
by all of our member companies."
Nearly 30 farms
are preparing to move to less ecologically fragile areas,
under orders from Canadian authorities.
Some farms have
installed underwater video cameras to detect when fish quit
feeding, so workers can stop scattering food pellets. Many
farms are switching to sturdier nets to stop fish from escaping
and keep out marauding sea lions, which are shot if they penetrate
the perimeter.
The industry now
recognizes that it will soon be pushing the limits of the
ocean.
"There will
come a time when our industry will use more of the fish oil
and fish meal than is available," said Odd Grydeland,
an executive at Heritage Salmon in British Columbia. "Our
biggest challenge is to find substitute grains for fish meal
and fish oil."
Farm-raised salmon
now dominates West Coast markets, arriving daily from Canada
and Chile. About 80 percent of the salmon grown in British
Columbia goes to markets from Seattle to Los Angeles.
The salmon industry
took off so fast in British Columbia in the 1980s that the
provincial government, worried about the environmental toll,
imposed a ban in 1995 on any new farms.
The industry responded
by stuffing, on average, twice as many fish into each farm.
Today, farms typically put 50,000
to 90,000 fish in a pen 100 feet by 100 feet. A
single farm can grow 400,000 fish. Others raise a million
or more.
The moratorium
on new farms was lifted in September by the provincial government
after voters elected a pro-business slate of lawmakers and
administrators. As a result, 10 to 15 farms are expected to
open each year over the next decade.
Five international
companies -- three of them based in Norway -- control most
of the existing farms. Nearly all are situated around Vancouver
Island, which begins outside Seattle's Puget Sound and extends
up the coast for 300 miles.
It's a lightly
populated place of stunning beauty. Cedar, hemlock and Douglas
fir grow right down to the high-water mark.
Massive tides flush
rich blue-green waters through the archipelago of islands,
straits, bays and inlets, nurturing five types of wild salmon.
These, in turn, attract seals, sea lions, white-sided dolphins
and the world's best-known pods of killer whales.
Residents rely
on boats and seaplanes to reach surrounding islands that host
many of the farms. Each farm is a cluster of pens, often interconnected
by metal walkways and tethered offshore by a lattice of steel
cables, floats and weights.
In the midst of
this idyllic setting, signs of strain on the marine environment
are bubbling to the surface much the way diseases and parasites,
incubated in European salmon farms, fouled the fiords of Norway
and the lochs of Scotland.
In Norway, parasites
have so devastated wild fish that the government poisoned
all aquatic life in dozens of rivers and streams in an effort
to re-boot the ecological system.
"The Norwegian
companies are transferring the same operations here that have
been used in Europe," said Pauly, the fisheries professor.
"So we can infer that every mistake that has been done
in Norway and Scotland will be replicated here."
Dale Blackburn,
vice president of West Coast operations for Norwegian-based
Stolt Sea Farm, said his staff works very closely with its
counterparts in Norway. But, he said, "It's ridiculous
to think we don't learn from our mistakes and transfer technology
blindly."
Still, more than
a dozen farms in British Columbia have been stricken by infectious
hematopoietic necrosis, a virus that attacks the kidneys and
spleen of fish.
Jeanine Siemens,
manager of a Stolt farm, said, "It was really hard for
me and the crew" to oversee the killing of 900,000 young
salmon last August because of a viral outbreak.
"We had a
boat pumping dead fish every day," she said. "It
took a couple of weeks. But it was the best decision. You
are at risk of infecting other farms."
Farms are typically
required to bury the dead in landfills to protect wild marine
life and the environment. But Grieg Seafood recently got an
emergency permit from the Canadian government to dump in the
Pacific 900 tons of salmon killed by a toxic algae bloom.
The emergency? The weight of the dead fish threatened to sink
the entire farm.
About 1 million
live Atlantic salmon -- favored by farmers because they grow
fast and can be packed in tight quarters -- have escaped through
holes in nets and storm-wrecked farms in the Pacific Northwest.
Biologists fear
these invaders will out-compete Pacific salmon and trout for
food and territory, hastening the demise of the native fish.
An Atlantic salmon takeover could knock nature's balance out
of whack and turn a healthy, diverse marine habitat into one
dominated by a single invasive species.
Preserving diversity
is essential, biologists say, because multiple species of
salmon have a better chance of surviving than just one.
John Volpe, a fisheries
ecologist at the University of Alberta, has been swimming
rivers with snorkel and mask to document the spread of Atlantic
salmon and their offspring.
"In the majority
of rivers, I find Atlantic salmon," Volpe said. "We
know they are out there; we just don't know how many, or what
to do about them."
His research focuses
on how Atlantic salmon can colonize, if given a chance. It
has terrified the U.S. neighbors to the north. Alaskan officials
banned fish farms in 1990 to protect their wild fishery. So
they don't take kindly to British Columbian farms creeping
toward their southern border.
Although native
Pacific salmon are rare and endangered in the Lower 48, Alaska's
salmon fisheries are so healthy they have earned the Marine
Stewardship Council's eco-label as "sustainable."
The council's labels are designed to guide consumers to species
that are not being over-harvested.
Recently, the prospect
of genetically modified salmon that can grow six times faster
than normal fish has heightened anxiety. Aqua Bounty Farms
Inc., of Waltham, Mass., is seeking U.S. and Canadian approval
to alter genes to produce a growth hormone that could shave
a year off the usual 2.5 to three years it takes to raise
a market-size fish.
Commercial fishermen
and other critics fear that these "frankenfish"
will escape and pose an even greater danger to native species
than do the Atlantic salmon.
"Nobody can
predict just what that means for our wild salmon," Alaska
Gov. Tony Knowles said. "We do see it as a threat."
Canadian commercial
fishermen, initially supportive of salmon farms, have grown
increasingly hostile. They were stunned in August when their
nets came up nearly empty during the first day of the wild
pink salmon season in the Broughton Archipelago at the northeast
end of Vancouver Island.
"There should
have been millions of pinks, but there were fewer than anyone
can remember," said Calvin Siider, a salmon gill-netter.
"We can't prove that sea lice caused it. But common sense
tells you something, if they are covered by sea lice as babies,
and they don't come back as adults."
Alexandra Morton,
an independent biologist and critic of salmon farms, began
examining sea lice in 2001 when a fishermen brought her two
baby pink salmon covered with them.
Collecting more
than 700 baby pink salmon around farms, she found that 78
percent were covered with a fatal load of sea lice, which
burrow into fish and feed on skin, mucous and blood. Juvenile
salmon she netted farther from the farms were largely lice-free.
Bud Graham, British
Columbia's assistant deputy minister of agriculture, food
and fisheries, called this a "unique phenomenon."
"We have not
seen that before. We really don't understand it," he
said. "We've not had sea lice problems in our waters,
compared to Scotland and Ireland."
Salmon farmers
point out that the sea louse exists in the wild. Their captive
fish are unlikely hosts, the farmers say, because at the first
sign of an outbreak, they add the pesticide emamectin benzoate
to the feed.
Under Canadian
rules, farmers must halt the use of pesticides 25 days before
harvest to make sure all residues are flushed from the fish.
If that's done, officials said, pesticides should pose no
danger to consumers.
European health
officials have debated whether there is any human health risk
from synthetic pigment added to the feed to give farmed salmon
their pink hue.
In the wild, salmon
absorb carotenoid from eating pink krill. On the farm, they
get canthaxanthin manufactured by Hoffman-La Roche. The pharmaceutical
company distributes its trademarked SalmoFan, similar to paint
store swatches, so fish farmers can choose among various shades.
Europeans are suspicious
of canthaxanthin, which was linked to retinal damage in people
when taken as a sunless tanning pill. The British banned its
use as a tanning agent, but it's still available in the United
States.
As for its use
in animal feed, the European Commission scientific committee
on animal nutrition issued a warning about the pigment and
urged the industry to find an alternative. But in response,
the British Food Standards Agency took the position that normal
consumption of salmon poses no health risk. No government
has banned the pigment from animal feed.
Scientists in the
United States are far more concerned about a pair of preliminary
studies -- one in British Columbia and one in Great Britain
-- that showed farmed salmon accumulate more cancer-causing
PCBs and toxic dioxins than wild salmon.
Scientists in the
U.S. are trying to determine the extent of the contamination
in salmon and what levels are safe for human consumption.
The culprit appears
to be the salmon feed, which contains higher concentrations
of fish oil -- extracted from sardines, anchovies and other
ground-up fish -- than wild salmon normally consume. Man-made
contaminants, PCBs and dioxins make their way into the ocean
and are absorbed by marine life.
The pollutants
accumulate in fat that is distilled into the concentrated
fish oil, which, in turn, is a prime ingredient of the salmon
feed.
Farmed
salmon are far fattier than their wild cousins, although they
do not contain as much of the beneficial omega-3 fatty acids.
The industry complains
that environmental activists have misinterpreted the contaminant
studies, needlessly frightening consumers.
"The concern
is that people will stop eating fish," said Walling,
of the British Columbia Salmon Farmers Assn. "Salmon
is a healthy food choice. Our Canadian government says this
is a safe food."
Environmentalists
in British Columbia and Scotland recently launched campaigns
urging consumers to boycott farmed salmon until the industry
changes many of its practices.
At the least, they
want the farms to switch to solid-walled pens with catch basins
to isolate farmed fish -- and their diseases, pests and waste
-- from the environment. The ideal solution, they say, is
to have the farmed stock raised in landlocked tanks.
Protests notwithstanding,
the industry is expected to get a lot bigger. Demand for seafood
is rising and will double by 2040, according to the U.N.'s
Food and Agriculture Organization. Nearly half the world's
wild fisheries are exhausted from over-fishing, thus much
of the supply will likely come from farmed seafood.
"Aquaculture
is here to stay," said Rebecca Goldburg, a biologist
who co-authored a report on the industry for the Pew Oceans
Commission. "The challenge is to ensure that this young
industry grows in a sustainable manner and does not cause
serious ecological damage."
L.A.
Times Dec. 9, 2002
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