12/05/2005– The increased
number of farmed salmon escaping into Norway’s
open waters puts wild salmon under greater
threat of disease, breeding difficulties and
genetic contamination, according to a new
report from WWF.
The global conservation organization’s report
shows that stocks of wild Atlantic salmon
are already depleted due to the existing threats
posed by dams and pollution.
With fish crammed tightly into cages in open
water, fish farming is an ideal breeding ground
for disease and parasites, such as sealice.
Escaped infected fish can then take these
diseases with them into the wild and infect
the non-farmed population.
Around half a million farmed fish escape
into Norwegian waters every year, meaning
one out of every four salmon or trout found
in Norway’s coastal waters are fish farm escapees.
“It’s totally unacceptable that such enormous
amounts of farmed fish have escaped from fish
farms into open waters, undermining the long-term
survival of wild salmon,” said Maren Esmark,
Marine Coordinator at WWF-Norway.
WWF’s report also shows that the up-river
migration of escaped farmed salmon late in
the spawning season physically displaces the
eggs of the already spawned wild salmon. This
effectively means that wild salmon’s reproduction
ability is being reduced.
This rise in the number of escaped salmon
has led to an increase in interbreeding between
the two varieties, which WWF says dilutes
the gene pool and threatens the survival rate
of offspring.
With 500,000 tons of farmed salmon and trout
produced per year, Norway’s fish farming business
is a cornerstone of the country’s economy.
However, according to WWF, Norwegian waters
remain home to half of the global stock of
wild Atlantic salmon.
“One third of Norway’s wild salmon stocks
are already suffering because of human activity,”
said Dr Simon Cripps, Director of WWF’s Global
Marine Programme. “Add to that the increasing
threat of escaped fish and we have to ensure
that industry and government clean up their
act and begin to act responsibly.”
WWF is also concerned about the increase
in escaped farmed cod from Norway’s expanding
cod farming industry and the effects this
can have on the already imperilled stocks
of wild cod. Escaped fish, whether they are
salmon or cod also represent an economic loss
for the industry.
The Norwegian government and the fish farming
industry have already taken some steps to
reduce the amount of escaped fish, but WWF
is urging for more to be done. These new measures
should include increased security to prevent
escapees, the individual tagging of farmed
fish, and the location of fish farms away
from vulnerable stocks of wild salmon or wild
cod.
