“Low oxygen availability” killed Northern Harvest salmon

Newfoundland Canada’s chief aquaculture veterinarian says warm water led to low oxygen levels causing mass mortalities at Mowi-owned salmon farmer, of which the number is still unknown.

CBC reports that despite union members saying that sea lice killed off a load of salmon in Newfoundland, Canada, in reality, warmer conditions that created low oxygen did.

The mortality was reported in late September and large numbers have been speculated but not confirmed.

Province veterinarian Daryl Whelan told the publication: “We’ve done the diagnostics and really, what’s occurred is not an infectious process that led them to the mortality. What’s led them to the mortality is the really low oxygen availability to them.”

Northern Harvest Sea Farms spokesperson Jason Card said that the event is causing them to look at redesigning its salmon cages.

“We have to act as though this temperature spike is not an isolated incident. We have to accept it as a new normal so that we are ready to deal with it,” Card said.

“So deeper cages, aeration systems, these are different ways that we can keep the water oxygenated, keep the fish cool and keep a good product going.”

Statistics are still being collected as the mortalities continue to be removed.