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May 2006, the New Brunswick government approved the 97th
salmon aquaculture site in the lower Bay of Fundy. These 97 submerged
Crown land leases now stretch from the New Brunswick - Maine border
including Campobello, Grand Manan and Deer Island, to just above Chance
Harbour (the latest approval, Haley’s Cove, is the easternmost site).
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(photo: Image Express)
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From
the small scale cottage industry of its origins (circa 1980), finfish
aquaculture, primarily salmon but now including cod and haddock, has
grown into an agri-food industry which sells its product on the world
market and competes with low-wage, sparsely regulated operations in
Chile and gigantic producers in Norway and Great Britain.
As
it has grown, most independent producers have been driven out of
business as product price plummeted and disease and parasite problems
plagued the densely packed fish farms.
Through consolidations and buy-outs, Cooke Aquaculture, a St.
George-based company, has emerged at the top of the pack, now owning
about 60 of the 97sites (including the new approval at Haley’s Cove).
The
industry’s troubles are the hallmark of all industrial agriculture
operations that sell into the world market. It is no place for the small
or the faint of heart. In
New Brunswick, even the mighty have fallen.
Heritage Salmon, a subsidiary of Weston Foods, and Stolt Sea
Farm, a Norwegian salmon aquaculture giant recently merged with Nutreco,
the world’s largest, both sold their east coast operations to Cooke
Aquaculture. Because Cooke
is a private company, it is not obvious who is financing their
phenomenal expansion, but all bets are on overseas money.
Besides
brutal economic rationalization imposed by a commodity market,
industrial production of finfish (as opposed to shellfish), like that of
hogs or other livestock, brings with it serious environmental and food
quality issues. The two
drivers of these impacts are scale and technology.
First,
scale. When this industry
began in the early 1980s, a large salmon farm was 30,000 fish.
Today, one cage on a multi-cage farm can contain this many fish.
As with most human activity, Mother Nature can absorb and recycle
waste products at a certain scale. However,
the bigger the scale, the more difficult such recycling becomes.
Eventually, Nature’s so-called carrying capacity is outstripped
and the environment becomes degraded, habitat is lost, and biodiversity
and productivity follow. That
is what has happened in the lower Bay of Fundy.
Second,
technology. Salmon and other
marine finfish are grown in nets suspended from floating frames, usually
plastic, in coastal waters. This
is referred to as open net pen systems.
Anyone wandering along the shore in the lower Bay of Fundy will
have seen the ubiquitous plastic piping of all sizes, either as whole
cages or in remnants, strewn about, sometimes hauled up for storage,
sometimes abandoned as industrial debris.
A salmon farm is made up of several so-called cages each holding
20,000 or 30,000 fish. Farms
range in size from a few hundred thousand fish to a million fish or
more.
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(photo: CBC)
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The
problem with open net pen technology is that all the waste from these
industrial operations is discharged directly - untreated and
undiminished – into the coastal waters. This waste is made up
primarily of fish faeces and urine, and waste feed.
This is not an unsubstantial waste stream.
For every tonne of salmon raised, 200 kg of solid waste is
produced, most of which is faeces. Liquid
waste is completely unaccounted for.
Total annual production in New Brunswick has ranged in recent
years between 30,000 and 40,000 tonnes, which in turn generates between
6,000 and 8,000 tonnes of solid waste discharged directly into little
coves and bays along the lower Fundy coast.
This
waste creates several problems. The
organic material settles out on the bottom, and where currents don’t
keep it scoured, builds up forming bacterial mats which deplete oxygen
and kills the little critters that live on and in the bottom sediments -
the base of the marine food chain. This
bacteria creates the conditions under which hydrogen sulfide gas, which
is toxic to fish, forms and off-gasses into the water column.
Further,
solid and liquid waste from fish farms contains high levels of nitrogen
compounds. Like phosphorus in fresh water, nitrogen fertilizers the
marine environment, creating algal blooms in the water.
When these blooms die, the decomposition process uses up oxygen,
robbing it from marine species that need it. This so-called
eutrophication process results first in species changes and then species
loss as the nitrogen loading continues. DFO research has revealed that
the Bliss Harbour - Lime Kiln Bay area near L’Etete, where salmon
aquaculture sites are most dense, is eutrophied and has suffered a
measurable loss of biodiversity.
Other
signs of eutrophication in fish farming areas include the loss of the
red species of seaweed and the presence of bright green mats of
enteromorpha, a nitrogen-fed fast growing annual algae that wreaks havoc
on the intertidal zone and beaches. A recently published study has also
demonstrated that under eutrophic conditions, elemental mercury which is
relatively inert, changes to methyl mercury which is quickly absorbed by
animals, creating mercury accumulation in the marine food chain.
This process has been found in Passamaquoddy Bay in particular.
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(photo: Boris Worm)
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DFO
research has also revealed the presence of antibiotic resistant bacteria
in the vicinity of salmon farms. This is the result of antibiotics which
have been administered to control salmon diseases being excreted by the
salmon and discharged into the water column. Sea lice, a parasite which
flourishes in a fish farm situation, is generally treated with systemic
drugs of the ivermectin-avamectin-emamectin family which are also
excreted into the environment with the potential to harm marine life.
Scientists
have also found that only 10 percent of all solid waste discharged from
salmon farms actually remains within the farm site.
The vast majority drifts offsite.
Yet environmental regulations only require fish farmers to
monitor bottom conditions on the farm site itself.
Most of the impact remains unmonitored and therefore unquantified.
Even
so, the annual monitoring program which measures oxygen and sulfide gas
levels under the cage sites, routinely finds about one-third of all
sites to be hypoxic or anoxic. These
are levels at which 60 to 90 percent of the different species found in
the sediments are wiped out.
Salmon
aquaculture is only viable economically as long as companies can
discharge waste untreated directly to the ocean.
While the cost is externalized to the industry, there is a steep
price to pay – polluted water, loss of marine biodiversity, coastal
dead zones, and a contaminated marine food chain.
