Low oxygen event hits Grieg in British Columbia

Grieg Seafood’s salmon farming operations in British Columbia were hit by a “low oxygen event” in May which affected fish health and led to a rise in sea lice levels, the company has reported.

Grieg said: “In May 2024, Grieg Seafood BC experienced a low dissolved oxygen event in Nootka Sound. This is a naturally occurring event which can affect the health and welfare of our salmon. At the same time as the low oxygen event, harmful plankton in the area also impacted some of our fish.

“Due to these adverse environmental conditions and in order to preserve the welfare of our salmon, we were unable to handle and perform sea lice treatments during this time, resulting in higher-than-normal sea lice counts for a short period of time.”

The company stressed that its operations have throughout the event maintained compliance with both DFO’s regulations and third-party certifier Aquaculture Standards Council (ASC) through the use of its Integrated Pest Management Strategy, which relies on AI technology to monitor and forecast oceanographic trends, treatments and sea lice mitigation tools.

The company added: “We were also able to draw upon the broader industry agreement to share mitigation resources, utilising mechanical and freshwater treatment vessels to treat multiple farms in the area as quickly as possible.”

Local news site The Coast Reporter said that officials from Canada’s Department of Fisheries and Oceans confirmed that mortalities from the event in May and June were between 4% and 26% at different farm sites.