Mowi Canada East has reported additional salmon mortalities at its operations in Newfoundland, along with mounting sea lice issues.
On 3 December, the company said an abnormal mortality event took place at its Little Burdock Cove site in Newfoundland, resulting in the deaths of more than 10 percent of the 382,113 fish being raised there.
“The suspect cause of the mortalities is a combination of sea lice pressure, treatments, and prolong rough weather at site,” Mowi subsidiary Northern Harvest Sea Farms said in a statement issued through the Newfoundland Aquaculture Industry Association. “NHSF is taking all responsible steps to address this matter under the oversight of the Newfoundland and Labrador Department of Fisheries, Forestry and Agriculture, and is following government approved policies for reporting.”
The fish at the site weighed an average of 1.1 kilograms, it said.
Sea lice have become an urgent problem for Mowi Canada East. On 4 December, it issued via required public reporting an update showing a dramatic increase in the average number of sea lice per fish at all its farm sites. In June 2021, the company averaged just 0.39 lice per fish, but the average increased to 1.73 in July 2021, 2.60 in August 2021, 4.65 in September, 7.09 in October 2021, and 14.2 in November 2021.
Mowi experienced several other mortality incidents at its Newfoundland operations in the third quarter of 2021, including a die-off that started at 93,000 and increased to 450,000 fish at a Marine Harvest Atlantic Canada site. Then, in October, farming sites in Little Bay, Chaleur Bay, and Friar Cove experienced mortalities of more than 210,000 salmon. Collectively, these issues – and the resulting “disappointing” quarter it faced financially – pushed the company to delay a planned expansion of its salmon farming in Newfoundland.
Making matters worse, Northern Harvest Sea Farms announced it detected infectious pancreatic necrosis (PIN) at one of its salmon at its Harvey Hill East marine site on 4 October, 2021.
“Strains of IPN virus that are endemic to Newfoundland and Labrador do not have a record of causing clinical signs of disease in Atlantic salmon raised on sea sites in Newfoundland. There has not been any increased mortality due to IPNv on any of Northern Harvest Sea Farms sites. IPNv does not infect humans and is not a risk to food safety,” the company said in a press release.
Mowi rival Cooke Aquaculture, which operates its Cold Ocean Salmon division in Newfoundland, reported much lower sea lice levels. Across all its sites in the province, the company never reported average sea lice levels higher than 0.09 per fish.
However, Cold Ocean Salmon confirmed it discovered infectious salmon anaemia (ISA) in one cage at its North West Cove site in Hermitage Bay. As a precautionary measure, all the salmon in the cage – "around 47,000" in all – are being harvested.
"Infectious salmon anemia virus (ISAv) is a naturally occurring virus in the ocean and is not a human health issue or a food safety issue,” Cold Ocean Salmon said in a release. “The company is taking all the responsible steps under the oversight of the Newfoundland and Labrador Department of Fisheries, Forestry and Agriculture and is following government approved policies for reporting.”
In 2020, Cold Ocean Salmon detected ISA at several additional marine cage sites in Newfoundland, including incidents at its Grip Cove, North of Killbuck Cove, Hood Cove, and Seal Cove sites, resulting in more than one million fish being harvested on an earlier-than-expected timetable.
Photo courtesy of Newfoundland Aquaculture Industry Association
