Fraser River to see record-breaking run of pink salmon

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British Columbia’s Fraser River is on track to see a massive run of pink salmon this year, possibly the greatest since recordkeeping began.

Around August and September, some 27 million pinks will be swimming upstream, almost doubling the last run’s numbers, according to Fisheries and Oceans scientist Kaitlyn Dionne.

Flying over the Barrière River, a tributary of the Fraser, Ms. Dionne said last year’s run looked “like a carpet of pink salmon from one end of the river to the other.”

While this surge of fish will be largely welcomed by a coast that has long seen crashing salmon stocks, it is not a straightforward gain. By competing with other, more commercially important species of salmon, the rising pink tide could have profound consequences for the ocean and the people who rely on it, according to Fisheries and Oceans scientist Brendan Connors.

Despite continuing declines in other salmon stocks across B.C., pink salmon populations have been growing rapidly, a trend seen across the North Pacific. In fact, there are more salmon in the Pacific Ocean now than at any time in the past century.

One driver of the increase is climate change, which is creating better conditions for salmon farther north while harming the B.C. populations in the south, Mr. Connors explained.

But “having more [pink] salmon in the North Pacific is not a net positive for British Columbia,” he said. “It means that those salmon from B.C. that do migrate far north have to compete with more mouths that are all looking for the same amount of food.”

Known for their rosy hue and pronounced humpback, pink salmon hatch in the streams of B.C. and Yukon before migrating out to sea, like all Pacific salmon. In the open ocean, salmon from all along the coast spend their adult lives mingling in the North Pacific, where they take advantage of the abundant food the Arctic waters provide.

When they get to the ocean, pinks grow fast, eating anything and everything. This speedy growth helps them dominate the ecosystem. By one estimate, pinks currently comprise almost 70 per cent of all the salmon in the Pacific.

This leaves little food for the rest of the salmon, compromising their growth, survival and populations. For sockeye in the Fraser, this competition for food has been even more impactful than climate change and is thought to be a factor in that species’ crashing stocks, Mr. Connors said.

And the competition doesn’t just affect other salmon species; it hits every level of the food chain, from plankton to humpback whales.

It hasn’t always been this way.

Around the 1970s, pink salmon populations started to tick upward. This coincided with Russian and Alaskan efforts to ramp up pink salmon hatcheries, which today produce an estimated 16 per cent of the species. (A negligible amount comes from Canadian hatcheries.)

Taking advantage of a warming Arctic and aided by those Russian hatcheries, pinks have expanded across Northern Russia and into Scandinavia, establishing themselves in waters far beyond their native range and threatening to replace the native Atlantic salmon. Already, there have been reports of pinks reaching the Canadian Arctic.

“Climate change is generally creating more favourable marine conditions at northern latitudes,” Mr. Connors said. “And that‘s allowed pink salmon to really explode. But that doesn’t explain what‘s happening in the Fraser.”

The Fraser runs past Vancouver and into lower B.C., near the southern extent of pink salmon’s range. Here, there is no climate-change-induced habitat expansion and little hatchery support, yet this summer‘s run is expected to beat any on record, according to Ms. Dionne.

This comes after a string of lucky breaks for Fraser River salmon that have led to improving returns of other species too, according to a report by the Pacific Salmon Foundation.

Coho and chinook salmon runs are also on the rise, yet their expected returns of 109,000 and 425,000, respectively, pale next to the pinks’ forecast run.

The past few years have seen less fishing pressure on the stock, not that it is high anyway. Pinks are not especially sought-after. Most of the commercial catch goes to canned salmon, a market dominated by Russia’s and Alaska’s hatchery-raised pinks, which often flood the market early in the season.

Two years ago, this brought Canadian pinks’ value “so low that it wasn’t worth the gas to catch them for the commercial fisheries,” Ms. Dionne said.

Other factors, including good weather and improved spawning habitat, have also helped Fraser River stocks.

“Fraser River pink salmon are an example of how resilient salmon are,” Mr. Connors said. When given a chance, “you can have a lot of salmon coming back.”

Even with their major comeback, the Fraser pinks may still be below historic levels. Before 1915, when a landslide cut off much of the upper Fraser, pinks were thought to come back in the order of 48 million per year, ­­according to one paper – almost twice this year’s expected run.

Pinks have long been a part of life for the First Nations up the coast.

According to Nathan Lustig, a fisheries biologist with the Scw’exmx Tribal Council, these large runs are “incredibly important to the bears and the eagles and everything that makes use of the salmon as they come home to spawn,” including people.

“ It gives us an opportunity for people to go fishing,” he added, an integral part of the community’s traditions.

For those who depend on the river for a living, enormous runs of pinks can be a boon.

Dean Werk, an Indigenous sport fishing guide in Chilliwack, says that while pinks have long been undervalued for fishing, their rise and simultaneous fall of other species mean they are becoming increasingly important.

He hopes that if pinks continue to come back like this, it will draw in anglers from abroad, the way sockeye runs used to do.

“If we take care of this, we’re gonna have a great run for generations to come,” Mr. Werk said. “It could be our salmon of the future.”