Fisheries and Oceans Canada’s decision to cancel underwater surveys of the declining herring population near Haida Gwaii is raising alarm among those concerned for the survival of the species.
Pacific herring stocks have declined an estimated 60 per cent over the past four years, according to biomass surveys done by Fisheries and Oceans Canada (DFO), which is responsible for monitoring the health of the species and setting quotas for fishing licences.
Due to COVID-19 safety concerns, dive surveys, in which divers count the number of eggs in an area to estimate the number of fish that will spawn, are being replaced with surface measurements to make biomass forecasts.
Surface surveys involve mapping and measuring herring spawn from the land, boats or, at times, airplanes.
Ian McAllister, executive director of conservation group Pacific Wild, said surface measurements don’t paint an accurate portrait of the spring herring spawn, which is used to determine responsible harvest quotas.
“If they’re not actually going down and looking at the survivorship of eggs, the thickness of the eggs and the distribution and abundance of them, which can only be done underwater, then it puts the forecast in significant question,” he said.
Each spring herring bring a unique spawning ritual to the B.C. coast. Thousands of tonnes of herring migrate to the shoreline to fill the water with eggs, usually deposited on seaweed and other plantlife, and milt, which turns the water a milky white for stretches that can be kilometres long.
The white waters are a telltale sign of the herring spawn, but only so much can be seen from the surface, said McAllister, who is working on a herring conservation campaign with Pacific Wild that aims to close the last herring commercial fishery in the Strait of Georgia.
Predators can consume an enormous amount of the eggs, which can also be dislodged by storms, he said.
“All that’s unknown unless you’re down below.”
Fisheries and Oceans Canada did not respond to The Narwhal’s request for comment after 11 days. It’s unknown whether dive surveys will return next year.
‘What is the harm of leaving too much in the ocean?’
Herring stock surveys — and the harvest quotas based upon them — have been a subject of roiling controversy in recent years.
In the Strait of Georgia, home to B.C.’s last commercial herring fishery, harvest quotas are based on a 20 per cent take of the estimated biomass.
In 2019, the quota was set based on a predicted return of 122,000 tonnes of herring, but fewer than 86,000 tonnes returned. As a result, an estimated 15 per cent of the season’s biomass was harvested.
Since then, calls have resounded for Fisheries and Oceans Canada to close the Strait of Georgia fishery.
Andrew Trites, a professor and director of the marine mammal research unit at the University of British Columbia, warns that without herring in our waters, there will be bigger problems.
“In B.C., herring is one of the most important species — it’s key prey for seabirds and for humpback whales, dolphins, harbor seals, for salmon and other fish,” he said, referring to herring as the “butter sticks of the sea.”
“They’re just full of fat. The key to life if you’re living in the ocean is having lots of fat in your diet, so the more calories, the better your chances are of surviving.”
Because many at-risk species depend on herring, including endangered chinook salmon and, in turn, orcas, Trites said careful stock assessments are crucial to ensure there’s an abundance to justify harvest.
“If you’re only looking at half a page of information … you have to be [cautious] of being too confident that you got it right,” he said.
“And what is the harm of leaving too much in the ocean?”
Herring, unlike salmon, are able to spawn for years throughout their lifespan. Female fish are harvested for their roe, while the male fish are ground up for pet food and are used in slurry to feed farmed salmon.
“They’re the last of the buffalo … the foundation of our whole coast,” McAllister said.
“And we’re just harvesting them to be grounded up into fish farm feed and garden fertilizer — that’s the real tragedy.”
Lack of data going forward a concern
McAllister said a dive survey could have easily been conducted within the bounds of social distancing protocols.
When herring fisheries initially shut down, Fisheries and Oceans Canada started conducting dive surveys to help with their recovery. He added he is concerned the absence of data will have negative effects going forward.
“Once they start eliminating all of these research projects and assessment projects, they rarely ever come back.”
“I think that having no information is powerful for DFO. … If the public no longer has access to that data and we have no way of assessing the health of these stocks, that’s in the DFO’s best interest because they just continue to deny that there’s a problem,” McAllister explained.
McAllister said he is worried Fisheries and Oceans Canada is “giving up on what once was one of the most productive herring locations on the B.C. coasts” if it permanently cancels the dive survey.
“Instead of the DFO being embarrassed every year for mismanaging the stock, they probably prefer to walk away from it.”