A federal Department of Fisheries and Oceans assessment earlier this month has revealed an increase in natural mortality in cod stocks off Newfoundland's south coast, and the stock will remain in the "critical zone" through the beginning of 2024.
In a presentation of the assessment's findings on Friday, stock assessment biologist Karen Dwyer said cod born in 2011 have been supporting the 3PS stock — between southern Newfoundland and St-Pierre-Miquelon — and the fishery over the last few years.
She said "recruitment" — fish younger than two years old — have dropped to historically low levels. Very few fish have been born in any one year since 2011, she said.
While some fish harvesters have indicated bountiful catches in the 3Ps zone, Dwyer said it's not proof of a rebounding stock.
"Our concern is that there's nothing coming behind that," she said.
The presentation noted the actual fishing mortality rate is the lowest it has been since the cod moratorium from 1994 to 1996.
In 2020-21 the reported catch was 1,780 tonnes, compared with 3,500 tonnes in 2019-20.
"While projections indicate there is a moderate-to-high likelihood that the stock will show modest growth in the short term, it's unlikely the stock will grow significantly in the near future," Dwyer said.
Dwyer said there have been "very slight improvements," but nothing that would indicate there was a huge improvement due to any one source.
"In fact, all our indicators are showing that the stock continues to be in poor condition," she said.
Some factors affecting the health of the cod stock could be the changes in the ecosystem, said Dwyer.
Ocean warming continues in 3Ps, she said, and early signs indicate that 2021 is on track to be one of the warmest years of the last half-century across the Newfoundland and Labrador shelves.
With warming waters the zone has seen an increased dominance of warm water fish, such as the highly predatory silver hake, and changes in the composition of the fish ecosystem..
"Different animals [are] moving into the area based on temperature. We are seeing more warm water fish such as silver hake," said Dwyer.
"A lot of fishermen will tell you they're seeing more Atlantic halibut. We don't know how this affects cod yet, but definitely seeing some changes in the fish structural community there."
What about seals?
Meanwhile, the debate over whether seals are among the biggest reasons for the deterioration of the cod stock in 3Ps is far from over.
"We already know that seals are eating a large amount of cod, but DFO needs their scientists to prove it first," Fish, Food & Allied Workers president Keith Sullivan said in a media release during Friday's presentation. "Yet several years into this and we've made very little headway."
Dwyer said the information from a survey of groups of seals in the area is still unavailable.
"We don't have the information to say there's a direct impact on cod stocks," she said.
"Until we have that information, we can't [say] that they're having a direct impact. We do have lots of info to show that prey availability is having an impact, so that's where we'd like to focus, but we are looking at seals."
Dwyer said DFO will continued to research stock dynamics and look at a stock-rebuilding plan.
The stock is co-managed by Canada and France, and DFO officials will consider advice from scientists and input from stakeholders in developing a mandate to negotiate future management actions of the stock with the French government in winter 2022.