March 22, 2019

No impact on lobsters from salmon farm operations

Eight-year study of lobsters below a salmon farm show no impact from the aquaculture operations on the crustaceans’ abundance, size or growth.

By SeaWestNews

An in-depth
eight-year study of lobsters living below a salmon farm off New Brunswick’s
Grand Manan Island has found that the aquaculture operations have had no impact
on the crustaceans.

The peer-reviewed,
industry-funded study was published this month in the Canadian Journal of
Fisheries and Aquatic Sciences.

It concluded that the
aquaculture operation had no impact on the crustaceans’ abundance, size or
growth in the area.

“There isn’t
anything like this. Any surveys that have been done have been sort of
cursory,” said Jon Grant, the study’s lead author and a Dalhousie
University oceanographer, according to a CBC report.

The study involved
divers visiting a sample area under the Benson Aquaculture salmon farm at
Cheney Head, off Grand Manan, in 2008, and returning every August and
September.

To establish a
baseline, surveying started before the fish farm opened. The study covered two
production cycles at the farm, which uses pesticides to control sea lice and
has been opposed by lobster fishermen.

It also included a
fallow period and a farm expansion to 336,000 fish from 10,000 during the
second production cycle.

An identical
survey was conducted about a kilometre outside the farm, reported CBC.

By the time the
project ended in 2015, divers had counted 1,255 lobsters inside the farm and
1,171 outside.

“In both
cases, whether it was on the farm or off the farm, over those eight years the
abundance of lobsters went up. A lot. By 100 per cent or more. And there was no
difference in those lobsters in any way — in their size, in their sex or their
abundance, whether on or off the fish farm,” Grant told CBC News.

“We don’t
detect any evidence that the fish farm affected behaviour, growth or abundance
of those lobsters.”

He said the study
proved one hypothesis: the population inside or adjacent to the farm matched
growth seen elsewhere in lobster fishing areas.

“It reflects
the fact that the fishery is ongoing and it’s thriving and that fish farming
does not seem to have impacted it, at least in eastern New Brunswick,”
said Grant, who is funded by New Brunswick-based Cooke Seafoods and holds the
NSERC-Cooke industrial research chair in sustainable aquaculture.

The surveys were a
requirement of the federal Department of Fisheries and Oceans and the New
Brunswick government. The Atlantic Canada Fish Farmers Association funded the
study.

The field work was
carried out by SIMCorp, a New Brunswick-based marine environmental consulting
firm that works for the aquaculture industry in Atlantic Canada and Maine.

Melanie Sonnenberg
of the Grand Manan Fishermen’s Association says a long-term study like this was
overdue and the results are good news.

But, she said it’s
just one location and more studies are needed.

“We still
need more information about the impact of medicated feeds and pesticides
especially in juvenile lobster,” Sonnenberg told CBC News.

(Image courtesy of Tourism New Brunswick)

Aquaculture, a key driver for global food revolution –
Lancet