No signs of herring stocks rebounding 2 years into moratorium, DFO says

Two years into a moratorium on the East Coast's spring herring fishery, biologists say the stock isn't improving.

Fisheries and Oceans Canada put a moratorium on fishing for herring in the Gulf of St. Lawrence, and on the mackerel fishery in Atlantic Canada and Quebec, on March 30, 2022.

At the time, the department said urgent action had to be taken to give the stocks a chance to recover and to ensure the long-term sustainability and prosperity of East Coast fisheries.

DFO biologist Laurie Maynard said that over the last two years of evaluation, the herring stock has plateaued at around 30,000 tonnes, but isn't showing signs of growth.

"The conditions that allow the fish to be able to rebuild are not there, and we don't expect them to be there," Maynard said.

"To be in the healthy zone, we would need a lot of young fish that survive to the age of maturity, and a little lower mortality in adult fish. For that to happen, it would require specifically lower temperature of [the] water."

Herring and mackerel play a vital role in both the fishing industry and ocean ecosystems. They are an important food source for other species, including tuna and Atlantic cod.

They are also a traditional source of bait in many commercial fisheries, including lobster, snow crab and halibut.

Fishermen across the region have expressed concern about the moratorium, but DFO says stocks have been in the "critical zone" for two decades now.

A marine heat wave in East Coast waters in 2023 didn't help things either.

Surface temperatures reached record highs throughout the region that summer, including a huge weeklong spike off Newfoundland that averaged 6.7 Cabove normal.

Norebound expected any time soon

Maynard said warmer water affects herring size, the ability of young fish to survive and the adults' ability to reproduce.

While she said she couldn't comment on when the moratorium might be lifted, Maynard said she doesn't expect the herring stock to rebound in either the short or long term because of those water temperatures.

"The biomass is so low that it has a lot of difficulty to rebuild to historical values."