Canada's lucrative snow crab fishery in the southern Gulf of St. Lawrence has had its certification as an environmentally sustainable fishery suspended.

The London-based Marine Stewardship Council (MSC) announced Tuesday it was suspending the certification — a stamp of approval for consumers — because the fishery has been linked to North Atlantic right whale deaths.

Twelve of the critically endangered whales died in the Gulf St. Lawrence last year, with necropsies performed on six.

MSC said two of the deaths in the area were attributable to snow crab gear. One whale was entangled in at least two sets of commercial snow crab fishing gear from Crab Fishing Area 12, the council said.

Another was found dead in fishing gear, including an older snow crab trap that the Department of Fisheries and Oceans said had not been in use for eight to 10 years.

Several other deaths were caused by ship strikes.

The fishery, which landed $129 million in snow crab in 2016 and employs hundreds of people, was first certified by the stewardship council in 2012.

MSC offers an easy way for consumers to spot sustainably caught seafood; products that are approved following a rigorous audit can display the blue MSC label — and typically sell at a premium price.

Audit findings

In January, federal Fisheries Minister Dominic LeBlanc announced new whale-protection measures for the Gulf of St. Lawrence, including reducing the amount of fishing rope floating on the surface and mandatory reporting of all lost gear — rules he said would be enforced aggressively. The department is expected to announce further measures soon.

The stewardship council suspension comes just months after the agency had given the Gulf of St. Lawrence snow crab fishery a five-year certification in October 2017.

Seafood products that are approved by the London-based Marine Stewardship Council following a rigorous audit can display this blue label. They typically sell at a premium price. (Eric Woolliscroft/CBC)

MSC said the whale deaths constituted "a major change in relation to the circumstances of the fishery." It launched an expedited audit last fall that concluded the fishery was no longer environmentally sustainable.

On Tuesday, auditor SAI Global concluded the "Gulf of St. Lawrence snow crab trap fishery no longer conforms with the MSC standard for sustainable fishing."

A notice of suspension specifying the date at which the suspension is effective and implications for the certificate holder will be posted on the MSC website.

90 days to come up with an action plan

The MSC client for the southern Gulf of St. Lawrence snow crab fishery certification is the Affiliation of Seafood Producers Association of Nova Scotia, which represents processors.

Seafood association executive director Peter Norsworthy told CBC News the industry has 90 days to develop and implement a corrective-action program. The fishery will be re-audited in the fall.

"It was the right decision. They followed their standard and measured it against what the Canadian government had stated in their own legislation under the Species at Risk Act. There is a zero-take limit on right whales," he said.

Environmentalist Shannon Arnold of the Halifax-based Ecology Action Centre said the 2017 right whale deaths were a wake-up call.

"The fleet has been really proactive, the government has stepped up to help them putting in measures," she said.

The suspension will affect fisheries in Area 12, which covers much of the southern Gulf of St. Lawrence, and the smaller Area 19 off western Cape Breton.

It does not affect the snow crab fishery on the Atlantic side of Nova Scotia.

The independent certifier SAI Global is expected to release a separate review of the Scotian Shelf snow crab fishery within weeks.