EventIn the Yukon River, Ichthyophonus infections surged during warmer water conditions, reaching up to 49% of Chinook salmon in 2022. The parasite causes white spots, mushy texture and a sour‑watermelon smell, and is linked to an ~80 % drop in returns that year. As a result, Canadian fisheries along the river are closed entirely through 2030 under the 2024 Alaska‑Canada agreement.
Scientists report that Ichthyophonus infection has surged in Yukon River Chinook salmon during warmer conditions, contributing to a steep decline in returns and prompting fishery closures on the Canadian side until 2030.
A warm‑condition thriving parasite is worsening salmon disease in the Yukon River, jeopardizing fish populations that span Alaska and Canada.
Scientists confirm the parasite Ichthyophonus is a major driver behind the sharp decline of Yukon River Chinook salmon. High infection rates—up to 49% in some sites—and warmer waters have linked the disease to an estimated 35 % rise in mortality at the Canadian border, contributing to fishing closures and jeopardizing subsistence food security.
