Nova Scotia-based firm Kelly Cove Salmon, whose parent company is Cooke Aquaculture, has scooped 10,000 dead Atlantic salmon from its fish farm near Liverpool on Nova Scotia's South Shore.
Although official sources revealed that the fish had died due to cold temperatures in their ocean pens, Joel Richardson, spokesperson for Cooke Aquaculture, said that technically the die-off is not classified as a "superchill" event because the water temperature did not fall to the required threshold of –0.7 C. Superchill occurs when the water temperature drops to the level that fish blood freezes, CBC News reported.
However, the ocean temperature at the site did, however, fall to –0.6 C last week.
Richardson said the die-off is a concern to the company, but losses due to cold water happen every five years or so.
"We obviously take a lot of care and pride in farming fish and the sea farming environment," he said. "But working with livestock and agricultural production, when you're growing fish and any other type of animals, there are occurrences that … do cause problems," the spokesperson told CBC News.
The last time a Cooke Aquaculture site in Nova Scotia had a case of superchill was in 2015.
The Coffin Island site consists of 14 cages that usually contain a total of about 400,000 fish, so the die-off last week represents about 2.5 per cent of the stock. The fish were removed and taken to a rendering plant in the province to be composted.
Cooke reported the incident to the municipality, the provincial Fisheries and Aquaculture Department and the federal Department of Fisheries and Oceans.
A spokesperson for the province said samples of the fish were analyzed by the department's veterinarians and early results indicate the deaths were due to "cumulative weather events."