Researchers are puzzled by an increase in salmon shark sightings near Kodiak, with unclear links to king salmon declines and insufficient data on shark populations and movements.

An increase in chum salmon in the Canadian Arctic, potentially linked to climate change, may be the same fish missing from Western Alaska, raising ecological concerns.

Experts decided that during the fishing season, red fish in the water area of the Anadyr estuary can be caught only two days a week. It was decided to introduce a large number of passing days to preserve the chum salmon population spawning in this basin.

Recent surveys reveal that chum salmon face challenges during winter in the Gulf of Alaska, with conditions like marine heatwaves affecting their diet and survival, leading to increased mortality rates.

In the much-higher water temperatures that lingered in the 2014-19 period, juvenile chum salmon metabolism was super-charged, meaning they needed more food, said the study, by scientists with the National Oceanic and Atmospheric Administration and the Alaska Department of Fish and Game. But the food that was available was of low quality — things like jellyfish instead of the fatpacked krill and other prey they normally eat, the study said.

Scientists from the University of Alaska Fairbanks have observed an increase in chum salmon spawning in North Slope rivers, potentially indicating a shift in their population and a signal of climate change. Elizabeth Lindley, a Ph.D. student working on the project, says that while evidence of spawning in a new region may be a positive for salmon, the impact on important subsistence resources including Arctic char and Dolly Varden is uncertain.

Potential new limits on the accidental catch of chum salmon by pollock trawlers are still years away from being implemented.

The Kuskokwim River king salmon run does not look particularly strong this year, but chum numbers look even worse. Historically, around 60% of the salmon in the river at this point in the season would be chum or sockeye, but right now Bethel Test Fishery numbers show that just over 20% of the salmon are.

About 189,000 fall chum had entered the Yukon River as of Sept. 7. At least 300,000 fish must enter the river before either Alaska or Yukon fishers can begin harvesting.

Usually Aug. 7 is the midpoint of the coho run, but this year it was not until Aug. 8 that numbers at the Bethel test fishery increased, and then only modestly.

Chum salmon die-off in the Kobuk River.