Chum salmon A species that has been unable to reproduce in the Interior Alaska river systems, are now reproducing further to the north in a few North Slope rivers, researchers have found.
The University of Alaska Fairbanks team in the month of April discovered about 100 Chum salmon which were either reproducing or had just flown into the Anaktuvuk and Itkillik rivers. These rivers are tributaries of the Colville River, which flows into the Arctic Ocean.
Its discovery that salmon is located far to the north was no surprise, as the five types of Alaska salmon have been seen in the Arctic said Peter Westley, an associate professor at the UAF’s College of Fisheries and Ocean Sciences and head in the study.
However, the discovery of the abundance of spawning chum that are found within the Colville tributaries was satisfying and confirms scientists’ theory that salmon are moving their range towards the northern part of their range as global warming heats their habitat to the south the scientist said.
“I was really thrilled to see everything become a reality,” said Westley, who studies the shifts in salmon populations. “It seemed as if we were trying to find a needle within the Haystack.”
The results confirm local reports of Chum salmon swimming around North Slope rivers. Additionally, the UAF research follows on from a prior discovery of the existence of a single juvenile Chum salmon in the Beaufort Sea lagoon, an earlier indication that the species is beginning to reproduce in that altitude.
To be determined, he added is the outcome of the chum-spawning chum that his team has discovered. The issue is whether the salmon that were found along the North Slope are occasional strays or the result of a longer-lasting change. He said: “Are they now a permanent fixture in the ecology or are they there for a few years but not all the time?”
The team is carrying out follow-up to monitor the findings. It includes genetic and chemical analysis, as well as measurements from thermometers put at the locations where the spawning chums were located, he added.
If water in the form of liquid remains all year round it is possible to have the possibility of a longer-lasting Chum salmon presence according to him. “If they are frozen solid then it’s basically the end of the line,” he said. “Salmon eggs aren’t able to survive in the event that they freeze.”
To date it has been pink salmon that have been the species that is most often observed at higher altitudes, Westley said. Pink salmon live in short cycles that are only 2 years long, which allows for faster population changes to be more likely according to researchers.
Chum salmon, even though they are a long time resident on the seas, share an attribute in common with pinks which may help make a shift to northwards easier to achieve, Westley said. As with pinks, but unlike coho, sockeye or Chinook salmon, chum salmon are able to spend much period in freshwater. “They typically only use rivers to spawn,” he said.
The catalyst for the spawning salmon initiative came from the Arctic salmon workshop that was held in conjunction with the Alaska Sea Grant program in Anchorage in December.
A North Slope resident who participated in the workshop, Robert Thompson of Kaktovik confirmed the increasing existence of salmon in the North Slope.
“When I first moved here, if anyone caught the chance to catch a salmon, they were the talk of town,” Thompson said. Thompson who started living for a short time at Kaktovik around the time of his 70s, and made the move permanent in 1988. Today, Thompson said that salmon are being caught frequently however, in smaller quantities.
“I’ve caught fish of every species -the king, silvers pinks, reds, chum and chum,” he said, by using alternative name of Chinook, coho and sockeye.
The appearance from salmon in the North Slope is similar to another shift in the waters that local people can harvest whitefish, Thompson said. “We’ve an animal species that is entering the waters, the cod saffron,” Thompson said.
Research conducted by U.S. Geological Survey found that saffron cod, which is a more southern-facing fish species that Arctic cod, has grown by 19-fold over the last thirty years within Beaufort Sea lagoons near Kaktovik.
There’s a worry that saffron cod could overtake other species of fish that local residents depend on, Thompson said.
“They could be, when there is only a limited amount of food,” he said.
There are divergent opinions about whether the shift to the north is beneficial or not.
In Nome and throughout the Western part of the Alaska’s Norton Sound region, commercial fishermen are taking advantage of the rising pink salmon populations. In the past year, in Norton Sound, more pinks were taken for commercial use in comparison to other species of salmon as per the Alaska Department of Fish and Game. This was in the wake of an astonishingly huge red salmon harvest in 2021..
In Norway the pink salmon is considered to be an invading species. The pink salmon in Norway battle for food with more sought-after Atlantic salmon. Additionally, the rotting carcasses of pink salmon after their spawning are considered as a source of pollution.
For those on the North Slope, the presence of salmon may have a positive effect, Thompson said. Thompson is planning to utilize the large mesh net next year to attempt to capture the most of them he added.
“It is nice they were established here, since they’re leaving in other areas,” he said.
Thompson mentioned declines in salmon further south, including the Yukon and Kuskokwim river system, as well as in other areas, and blamed climate change for the decline.
“I believe that the majority of people aren’t considering climate change enough,” he said. “When there’s the entire Yukon River shut down and fishermen have been fishing for many thousands of years, it’s very serious.”
