The recent release of a study into the impacts of a fish farm in Port Mouton Bay has fishermen calling for the site to be dismantled.
It was published in the international journal Marine Ecology Progress Series on June 28.
The study looked at lobster catch rates in the bay in the last two weeks in May, every year for 11 years.
Marine biologist Inka Milewski, who oversaw the study for the last four years, explains what was found.
“What we found was during periods when the fish farm was actively raising fish, market catch across all regions, dropped by 42 per cent,”
She says the egg bearing lobster counts also dropped by an average of 52 per cent when the farm was active.
Milewski believes an odour plume from the farm may be affecting the lobsters ability to detect food and therefore they’re not finding their way into the traps.
The study also looked at other factors like temperature but found the bottom temperature in the area is not significantly different during feed and fallow years.
The low oxygen conditions and dissolved sulphides and ammonium that can be produced in large quantities as a result of the waste released from net pen fish farms are known to have behavioural and toxic effects on lobsters,” says Milewski.
Local fishermen from 15 different boats took part in the study over the years.
It was conducted during the last two weeks in May in part because that’s when lobster are known to migrate into the area and because the lobsters are not moulting at that time.
The fish farm, now owned by Ocean Trout Farms, has seen opposition from residents and fishermen for years but has been fallow and has not had fish stocked since 2015.
It lead to the creation of an advocacy group called Friends of Port Mouton Bay, protests, signage, and requests from government to remove the site.
Many argue Port Mouton Bay is too shallow to support a fish farm and does not have the flush capacity to remove waste and excess food from the protected bay.
Bob Swim has been fishing in Port Mouton Bay for around 50 years.
He was quoted in a press release announcing the study results and asked the government to ‘immediately and permanently’ decommission the site.
Swim says crews have been forced to go further and further out to sea to catch lobster since the fish farm was built in the 1990s.
Bruce Hancock, head of the aquaculture division of the Department of Fisheries and Aquaculture, says that’s a trend they’ve seen in other parts of the province, regardless of fish farms.
However, he says the department will be looking into both the concerns around the farm and the newly released study.
The province introduced new regulations around aquaculture in 2015 which tightened standards and now involves Nova Scotia Environment to tackle complaints.
Hancock says those new regulations will ensure the site can be run well, if Ocean Trout Farms chooses to restock.
“Every site before it is stocked has to get permission to stock and that’s based on their environmental monitoring results,” he says adding that sites are regulated case by case.
Hancock says that may mean the site will have to stock less fish as the level of fish has to be approved by the department.
Story by Brittany Wentzell
Twitter: @BrittWentzell
Email: wentzell.brittany@radioabl.ca
