Despite some encouraging numbers from fish counting and test fisheries for the earlier runs of Fraser River sockeye, as well as pink salmon returns in the Campbell River area, scientists involved in a winter ocean survey are warning that the late summer sockeye run – typically the most abundant – could be well below the pre-season forecast.
Every four years, Fraser River sockeye tend to return in greater abundance, and the late summer run (notably Adams River) typically makes up 60% of total returns.
This year’s pre-season forecast for all Fraser River sockeye was 9.8 million. As of August 9, fish counts and test fisheries put Fraser River sockeye returns at 996,100.
The early Stuart population have returned in much higher numbers than expected. But the late summer run, dominated by the Adams River population, may not return in the abundance that was expected, according to preliminary findings of the 2022 Pan-Pacific Winter High Seas Expedition.
The ocean surveys have been conducted three times since 2019, with scientists catching salmon in the open North Pacific and doing a range of tests, including DNA sampling to determine where the fish originate.
The last ocean survey was larger than the previous two, with more vessels covering a wider range of the Pacific Ocean.
The most surprising finding from the 2022 winter ocean survey was the abundance of sockeye, said Dick Beamish, the Fisheries and Oceans scientist emeritus who has been a lead organizer of the surveys.
“The largest catch was sockeye salmon,” Beamish said. “It should not have been. Sockeye salmon are only 15% of the salmon in the ocean. We should not have caught so many sockeye.”
But DNA testing suggests few of the sockeye caught at sea were Adams River sockeye.
While it could be that those salmon were simply outside of the survey area at the time it was conducted, it could also suggest a comparatively poor return this year of what has traditionally been the most abundant population of sockeye in B.C. – one that typically supports a commercial fishery.
“Although these data are preliminary, the low catch rate of late-run Fraser River sockeye salmon in the winter 2022 Gulf of Alaska survey is a signal that returns of late-run sockeye salmon may be even smaller than the pre-season forecast suggest,” DFO scientists involved in the survey write in a brief to the Pacific Salmon Commission (PSC).
Adams River sockeye caught on the high seas were two to three times lower in number than would have been expected.
“It’s too early to say the science is showing us this, but I think what we’re going to see is actually a poor return of sockeye to the Fraser,” Beamish said. “The sockeye that we found were coming back to areas that are not necessarily to the Fraser.”
It is still too early to tell from test fisheries how the late run is doing. As for the summer run, so far the returns are “not encouraging,” said Brian Riddell, science advisor and former CEO of the Pacific Salmon Foundation, and co-organizer of the Pan-Pacific High Seas Expedition.
Meanwhile, there are anecdotal reports of fairly robust pink salmon returns in the Broughton Archipelago area, leading to speculation by some that the removal of open-net salmon farms from that area in 2019 and 2020 might have something to do with this year’s better returns.
“This year’s significant rebound in pink salmon returns present compelling evidence that it is the salmon lice sloughed-off from open-net salmon farms that was (and remains) the primary cause of critical declines in the returns of wild salmon,” the First Nations Wild Salmon Alliance (FNWSA) said in a press release.
Unlike other species of Pacific salmon, pink salmon live for only two years. The pinks returning now would have migrated to sea in 2020, after some salmon farms in the Broughton Archipelago had been removed.
Whereas pink salmon in that area returned in the hundreds in 2020, there is anecdotal evidence of pink salmon returning now in the thousands, said Bob Chamberlin, chairman of the FNWSA.
But 2020 is a bad yardstick to measure by. That was the year when the commercial catch for various species of salmon throughout the Northern Pacific was one of the lowest in decades. Returns this year of any species of salmon might look good in comparison to 2020.
The Department of Fisheries and Oceans’ counting of salmon in areas like the Broughton Archipelago is spotty, so it may be hard to gauge just how this year’s return of pink salmon compares to previous years.
One area where salmon are counted is the Quinsam River, which has a hatchery, in the Campbell River area, and the results so far suggest some very healthy returns of pink salmon.
“They’re indicating a very good return of pinks,” Riddell said. “In-river visual count of over 150,000, so that’s a nice message, early on, and that would bring the good returns right down into Campbell River.”
But it would be premature to ascribe this year’s pink salmon returns to the removal of salmon farms, as there are so many other variables at work that might explain either increases or decreases in returns.
“It’s quite possible that Bob’s right – that there was some additional benefit (to removing salmon farms),” Riddell said. “Would it be attributed to the whole return? Well, no. There’s never going to be a single factor. It’s not common that it’s a single factor, but it definitely could contribute.”
The trend of declining salmon abundance in B.C. has been mirrored in Japan, Beamish notes.
Generally, more southern ranges, like Japan and B.C., are seeing salmon populations collapsing, while more northern regions experience growth in abundance – 2020 being one exceptional year in which even northern regions saw declines.
“Japan is seeing the same collapse in their chum salmon as we are seeing,” Beamish said. “And it’s at about the same times.
“Their commercial catches have declined from about 240,000 metric tonnes to 57,000 metric tonnes. So they’re seeing a 70% decline, and there’s no salmon farms in Japan.”
Generally, what the ocean surveys have been telling scientists is that there has been a literal sea change that is making the traditional modelling for predicting salmon abundance less accurate.
“Almost all scientists will agree that what is happening is that the ocean eco-systems are now changing, as a result of climate change, in a way that no longer can be predicted based on past dynamics,” Beamish said.
“What it is telling science is that we need to see a bigger picture about what regulates Pacific salmon.”