Why the Yukon River salmon surge isn’t a clear sign of recovery

Since the fall run began in mid‑July, Fisheries and Oceans Canada estimates that about one million chum salmon have entered the Yukon River from the Bering Sea – roughly three times the usual flow.

Even with the surge, only about 12 % of the returning fish are of Canadian origin, far below the typical 20‑30 % share recorded in previous years.

Researchers note that chum salmon numbers fell sharply in 2020, and they still do not know why the population dropped then rose again this year.

"It’s very worrying, and not least because we don’t really know why the numbers have gone down, just like we don’t know why the numbers came back up this year," said Sebastian Jones, wildlife analyst at the Yukon Conservation Society.

Jones added that the situation shows how little control or understanding we have of some of these ecosystems.

The long‑term goal is to see 150,000‑250,000 chum salmon entering the Yukon each season, but current estimates remain far below that target.

Scientists point to rising water temperatures and increased industrial trawl fishing in the Bering Sea as possible influences, though they admit the exact impacts on salmon are not fully understood.

Stephanie Peacock, a scientist with the Pacific Salmon Foundation, explained that chum salmon provide an important nutrient source later in the fall, and she cautioned that the overall decline of both chum and chinook salmon remains a serious concern.

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