Salmon farming in crisis: 'We are
seeing a chemical arms race in the seas'
Rare only 40 years ago, farmed salmon
is now taken for granted in our kitchens. But the growth of the industry has
come at great cost
John Vidal
Saturday 1 April 2017 11.00 BST Last modified on Saturday 1
April 2017 11.15 BST
Every day, salmon farmers across the world walk into steel
cages – in the seas off Scotland or Norway or Iceland – and throw in food. Lots
of food; they must feed tens of thousands of fish before the day is over. They
must also check if there are problems, and there is one particular problem they
are coming across more and more often. Six months ago, I met one of these
salmon farmers, on the Isle of Skye. He looked at me and held out a palm – in
it was a small, ugly-looking creature, all articulated shell and tentacles: a sea
louse. He could crush it between his fingers, but said he was impressed that
this parasite, which lives by attaching itself to a fish and eating its blood
and skin, was threatening not just his own job, but could potentially wipe out
a global multibillion-dollar industry that feeds millions of people.
“For a wee creature, it is impressive. But what can we do?”
he asks. “Sometimes it seems nature is against us and we are fighting a losing
battle. They are everywhere now, and just a few can kill a fish. When I started
in fish farming 30 years ago, there were barely any. Now they are causing great
problems.”
Lepeophtheirus salmonis, or the common salmon louse, now
infests nearly half of Scotland’s salmon farms. Last year lice killed thousands
of tonnes of farmed fish, caused skin lesions and secondary infections in
millions more, and cost the Scottish industry alone around £300m in trying to
control them.
Scotland has some of the worst lice infestations in the
world, and last year saw production fall for the first time in years. But in
the past few weeks it has become clear that the lice problem is growing
worldwide and is far more resistant than the industry thought. Norway produced
60,000 tonnes less than expected last year because of lice, and Canada and a
dozen other countries were all hit badly. Together, it is estimated that
companies across the world must spend more than £1bn a year on trying to
eradicate lice, and the viruses and diseases they bring.
As a result of the lice infestations, the global price of
salmon has soared, and world production fallen. Earlier this year freedom of
information [FoI] requests of the Scottish government showed that 45 lochs had
been badly polluted by the antibiotics and pesticides used to control lice –
and that more and more toxic chemicals were being used.
The salmon-farming industry, which has grown at breakneck
speed since the 1970s, knows it has a huge problem, but insists it sees the
lice as unwelcome guests that will soon be evicted rather than permanent
residents. Rather than dwell on the lice, industry leaders point to the fact
that in just 40 years, aquaculture has gone from providing 5% of the world’s
fish to nearly 50%, and in Scotland, from a few hundred tonnes of salmon a year
to more than 177,000 tonnes in 2015. They argue that new methods to control
infestations are being developed and the chemicals being used are safe and
degrade quickly, adding that they expect to have found a solution within a few
years.
“Sea lice are a natural phenomenon,” says Scott Landsburgh,
chief executive of the Scottish salmon producers association. “All livestock on
farms, terrestrial or marine, are encountering some kind of parasite or tick,
and they’re dealt with. And that’s part of livestock farming. We are no
different to terrestrial farms. Problems come and go, depending on biology and
the environment. The louse is a hardy parasite. It’s a challenge for Chile and
Norway, too. We are spending a lot on all sorts of things.”
The global companies that dominate ownership of the farms,
buoyed by high prices and growing worldwide demand, are confident that they
will find solutions. Marine Harvest, the giant Norwegian multinational that
grows 40,000 tonnes of salmon in its many Scottish farms, said this week that it
needs to develop more effective ways to combat lice. “As a relatively young
industry, we hope that through industry collaboration, research, transparency
and sharing of knowledge, we can make the necessary changes to do better, and
keep getting better,” says Alf-Helge Aarskog, CEO. “One company alone cannot
solve all sustainability challenges.”
Meanwhile, they urge the public to celebrate the fact that
the Atlantic salmon, which used to complete an extraordinary journey across
oceans to breed in British rivers, is now taken for granted in our kitchens
and, in an act of ecological democratisation, has been transformed from
something special enjoyed by the few into the most popular fish eaten in
Britain.
‘They are everywhere now, and just a few can kill a fish’ …
the Lepeophtheirus salmonis, or the common salmon louse. Photograph: Alamy
If the nemesis of the farmed Atlantic salmon is the sea
louse, then Don Staniford, who runs the small Global Alliance Against
Industrial Aquaculture, is the industry’s persecutor-in-chief. The former
University of East Anglia scientist turned activist and investigator has spent
20 years tracking the industry, seeing it grow from a shrimp into a shark,
which, he says, is now close to destroying itself.
I last heard Staniford talk in London in 2012, when he gave
a lecture at the National Geographic Society, calling fish farms “toxic
toilets” and warning that diseases were rife, waste was out of control and the
use of chemicals was growing fast. Not only were fish farms getting bigger, he
said, they were also becoming reservoirs for infectious diseases and parasites.
It was a shocking, revealing talk. I did not know that farmed salmon were fed
partly on fishmeal and fish oil, often derived from ocean fish such as
anchovies, herring and sardines. Despite industry claims that industrial
aquaculture feeds the world’s poor, it seemed that the big farms were adding to
the pressure on the depletion of the oceans.
Staniford, a Liverpudlian who has lived in Scotland for many
years, argued that cramming carnivorous, migratory fish into crowded tanks and
releasing toxins, diseases and parasites into the surrounding waters was
inherently unsustainable. Unless the global salmon farming industry drastically
changed course, he said, it would collapse.
This week I asked Staniford what had changed since then.
Little, he replied, except that the farms had got bigger, the industry was
spending even more heavily to control the lice, more fish were dying in
appalling conditions and the pollution caused by their waste and the use of
chemicals was becoming more serious. He has spent the past five years labelled
an “eco-terrorist”, a “troublemaker”, an “exaggerator” and “a prophet of doom”.
He has been sued by the industry for defamation, lost a high-profile Canadian
high court battle, been heavily fined, been threatened many times, and been
ordered never to repeat statements such as “wild salmon don’t do drugs” and
“salmon farming spreads diseases”.
“He is an ace troublemaker. He annoys everyone … but he uses
freedom of information requests to get his data and 99 times out of 100 he is
right”, says Scottish investigative journalist Rob Edwards. “I am a trained
scientist. I use peer-reviewed science and use the industry’s own figures,”
says Staniford.
“What we are seeing now is a chemical arms race in the seas,
just like on the land farms, where the resistance of plants to chemicals is
growing. In fish farms, the parasites are increasing resistance to chemicals
and antibiotics. There has been a 10-fold increase in the use of some chemicals
in the past 18 months.” The farms are now turning to mechanical ways to delouse
the fish, he says. “They are using hydro-dousers, like huge carwashes, and
thermal lousing, which heats them up.” There is also the spectre of GM salmon,
with companies engineering GM plants for their omega-3 to feed the fish, and a
US company given permission to develop GM salmon.
“Whichever way you
look, the breeding of carnivorous fish is a nightmare. It is environmentally,
socially and economically bankrupt. It’s coming to a crisis point for the
industry. Some chemicals will be banned soon, and unless something significant
happens, the industry will have to invest very heavily.”
The use of chemicals, especially, worries him. Last month
Staniford unearthed the fact that not only was the use of the toxic drug
emamectin rising fast, but also that the industry had persuaded the Scottish
environmental protection agency to withdraw a ban planned for next year. Other
papers showed that the levels of chemicals used to kill sea lice have breached
environmental safety limits more than 100 times in the last 10 years. The
chemicals have been discharged into the waters by 70 fish farms run by seven
companies.
Support is growing for an investigation into the links
between the industry and government. Richard Luxmoore, senior nature
conservation adviser to the National Trust for Scotland, told the Daily Record
in February: “The environmental standards have been put there for a good
reason. It is highly worrying that they have been breached so many times. This
is yet more evidence that the chemical warfare waged by fish farms against sea
lice has essentially been lost, and the application of toxins to kill them is
spiralling out of control.”
Meanwhile, FoI documents obtained by Stanimore show that the
Scottish industry wants to “innovate” by building the world’s biggest salmon
farm, which would triple the size of the largest now in operation. It could
farm 2m fish at a time, and create as much waste as a city the size of Glasgow.
“It would be an ecological disaster,” says Stanimore.
The answer to the inevitable lice problems, say
environmentalists, is to move the farms further offshore into deeper, colder
waters, where lice are less able to survive, or to even put them on land, where
they could be better controlled. But this would add greatly to industry costs
and require investments of billions of pounds. In the meantime, the companies
are using mechanical ways to trim the lice from the fish. These range from
pumping the fish through water hot enough to make the lice let go of their
hosts, to churning them as if in a washing machine. Both are condemned by
animal welfare group Compassion in World Farming, and are known to be expensive
and not always effective. Last year the heating of the water on a Skye fish
farm led to the accidental slaughter of 95,000 fish. Another 20,000 died in
another incident.
“Many farmed fish are fed largely on wild fish. To produce
farmed fish such as salmon, it takes about three times the weight of
wild-caught fish. This is not only unsustainable, but adds to the serious
welfare concerns about how wild fish are caught and slaughtered,” said a
spokesman.
The smart money is now on breeding wrasse, a small fish that
eats lice. It is being widely piloted and is highly promising, says Landsburgh.
“We have about 100,000 fish and the wrasse have cut our losses enormously. We
haven’t had to use chemicals since August 2014. Most fish farms are
overcrowded, but we are not. We find lice very occasionally but 99% of the time
we are completely clean,” said Pete Robinson, a worker at the Wester Ross
salmon company in Ullapool. But even using wrasse is not a complete answer. New
scientific studies showed this week that fish farms may be depleting wild
wrasse numbers too, and to breed enough for all Scottish farms could take four
or more years, says Landsburgh. “But we have to keep at it. The louse is a
hardy parasite. We are doing our damnedest to eradicate it,” he said.
“There’s no right way to do the wrong thing,” says
Stanimore. “The simple solution is to just stop.”
Salmon: the facts
• Salmon is the biggest-selling seafood in the UK. Most UK
production is carried out by six Norwegian companies. There are about 250
salmon farms off the west coast of Scotland and its islands
• 60% of Scottish farmed salmon is sold to British
consumers. Export markets are led by the US, which bought 30,000 tonnes in
2015. UK sales are more than £700m a year
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• Farmed salmon are fed on oil and smaller fish, ground-up
feathers, GM yeast, soybeans and chicken fat
• Wild salmon get their colour from eating krill and shrimp.
The flesh of farmed salmon is grey, and is coloured by astaxanthin, a
manufactured copy of the pigment that wild salmon eat in nature
• Fish is an important part of a healthy diet, and salmon
are a good source of omega-3 fatty acids that can reduce the risk of
cardiovascular diseases
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