A fat pink salmon atop a multi-species harvest in Utqiagvik last year/Craig George photo

The Alaska Arctic appears to be home to global-warming winner familiar to almost everyone in the 49th state: pink salmon.

Impossible to miss for those fishing in the “Top of the World” outpost of Utqiagvik (formerly Barrow) last year, the salmon most Alaskans call a “humpy” has now caught the attention of scientists with the National Oceanic and Atmospheric Administration (NOAA).

“As temperatures rise and sea ice melts, some species will do better than others,” the federal agency reported in a story on its website Monday. “A new study suggests that pink salmon may be one of those species.”

The story highlights one of the least discussed aspects of climate change, the possibility of positive changes or what humans might view as potentially positive changes in some places around the planet.

Against the backdrop of doom associated with most climate-change reporting, the headline on the NOAA story borders on shocking: “Pink Salmon May Benefit as Pacific Arctic Warms.”

The results of research conducted by scientists from the U.S. and Canada “supports the hypothesis that warming air temperatures in this region (as
a proxy for river and stream temperatures) may be improving freshwater
production leading to higher numbers of juvenile pink salmon in the
northern Bering Sea region during summer months,” the study itself says.

Improving freshwater production due to warming has previously been linked to the boom in sockeye salmon at the southern edge of the Bering Sea, which is now witnessing Bristol Bay returns so large fishermen and processors sometimes can’t keep up with harvest goals. 

These studies come on the heels of another that concluded there are now more salmon than ever in the Pacific Ocean, most of them pinks, and a global examination of phytoplankton production that led Swiss scientists to conclude ocean warming is making the marine environment more productive.

In the ocean as on land, plants are at the base of the food pyramid. They provide the energy consumed by omnivores and herbivores, like cattle, eaten by carnivores, like humans. More plants in the ocean would be expected to support more animals – in this case, pink salmon.

Table fare

Middle-tasting fish, pinks are not exactly Alaska’s culinary favorite. More flavor-filled sockeye (red), king (Chinook), silver (coho), and “keto” or chum (dog) salmon are generally preferred.

But there is something to the idea that any salmon is better than no salmon.

“In the past on the North Slope, salmon have been used for dog food and even considered nuisance fish when interfering with preferred species such as aanaakliq or broad whitefish in the inland rivers,” the NOAA story quotes North Slope Borough biologist Todd Sformo observing. “(But) recently, there seems to be a change both qualitatively and quantitatively in the use of salmon as a main dish and for smoking.”

Pink salmon are certainly edible.

“…Many fishermen believe the pink is good for nothing but canning or halibut bait,” San Fransisco journalist Alastair Bland wrote in Smithsonian Magazine. “Others – like this writer – have found sea-bright pinks to be excellent when wrapped in foil, seasoned and grilled.”

Pinks are unlikely to be used for halibut bait in an Alaska Arctic with no established halibut fishery, though that too could change. Russian scientists last year reported finding significant halibut stocks in the central Arctic Ocean.

Those researchers have come to believe “the climate changes of the past decade have swept away the borders between Arctic, Atlantic and Pacific water masses, including the respective characteristics of these waters, and lead to the shift in marine life in the oceans,” The Independent Barents Observer later reported.

The Norway-based publication went on to suggest that the marine resources identified during a Russian-sponsored trans-Arctic expedition in 2019 are “likely to soon lead to the start of commercial fisheries in the area.”

Alaska’s Arctic fishery

Alaska already has an Arctic salmon fishery in Kotzebue Sound about 30 miles north of the Arctic Circle, but there have been continuing problems in finding buyers for pinks in the region. Processors find it hard to compete with massive pink salmon fisheries operating at an industrial level in Prince William Sound, Southeast Alaska, and on Kodiak Island.

Thus the growing Arctic population of pinks looks to continue as a food source used mainly to feed local residents around the Arctic rim.

East of the U.S. border in the Canadian arctic, locals have been reported to be taking advantage of not only a pink boom but an increase in chum salmon as waters warm. Some sockeye are now also reported to be showing up.

“The salmon frenzy that started in the western Arctic earlier this year has gone on to reach a historic high,” the CBC reported last year. “Karen Dunmall, a biologist with Fisheries and Oceans Canada, said they got more salmon from harvesters in the western Arctic and Nunavut this year than in the last 20 years combined.

“Starting in 2004, pink salmon started showing up in the even amount of years … (and) more recently in 2016 and ’17, sockeye appeared,” Dunmall told the Canadian news agency.

Even-year pink salmon are genetically distinct from odd-year pink salmon. Canadian biologist James Irvine and colleagues have suggested this is due to a prehistorically “more southerly glacial refugium for odd-year than for even-year pink salmon and temperature-related survival differences between these broodlines.”

Even-year and odd-year pink salmon broodlines do not overlap due to the short lifespan of the species. Spawned in late summer in streams along the U.S. West Coast and the Russian East Coast, pink salmon eggs hatch over the winter and the young fish go to sea in the early spring.

They spend only about 18 months in the ocean before returning to spawn as 3.5 to 4-pound adults. The odd-year spawned pinks are far at sea fattening up while the even-year pinks are arriving back at their spawning waters and vice versa.

Too much

Irvine is among the scientists now starting to wonder if the bounty of pinks might actually be too much of an otherwise good thing.

Scientists from the University of Alaska Fairbanks, the University of California, Canada’s McGill and Simon Fraser universities, Virginia Polytechnic Institute and State University, the Washington Department of Fish and Wildlife, the Alaska Department of Fish and Game, and GKV & Sons, an independent consultancy, last month implicated pinks in a decade’s long decline in the size of king, red, silver and chum salmon.

In a peer-reviewed study published in Nature Communications, they reported examining a dozen possible reasons for the shrinkage that found plenty of environmental determinants from year to year but “the only consistently negative effect across all species was that of Alaskan pink salmon abundance, although this effect was weak in most species.

“(But) intriguingly, the shared acceleration of size declines post-2000 occurred during a period of unusually high (though variable) pink salmon abundance in Alaska, suggesting high pink salmon abundances could be accelerating or exacerbating size declines. Our results provide further evidence that wild and hatchery-enhanced pink salmon abundance in the North Pacific has reached such high levels that they appear to be exerting an influence on ecosystem structure and function.”

The suggestion that Alaska hatchery production of large volumes of low-value pinks could be affecting the size of high-value king, red and silver salmon and possibly the volume is highly controversial.

Hatcheries have built a robust fishery in Prince William Sound and are now considered vital to the economy of that region of the state. Alaska has long prided itself on avoiding salmon farming with its associated environmental issues in favor of what is called “ranching.”

Ranching involves artificially inseminating eggs, hatching them in environmentally controlled facilities, and then raising the little fish to the absolute best size for maximizing their chances of survival in the ocean.

Adult fish produced in this way are then harvested when they return and marketed as “wild caught.” The hatcheries in the Sound and on Kodiak Island have at times accounted for nearly half of the huge pink salmon catches that have kept the decadal average harvests of Alaska salmon growing since the 1980s.

Sound harvests that averaged 3 million per year from 1951 to 1979, now average about 45 million pinks per year, a 15-fold increase over the historic catch, according to the Alaska Department of Fish and Game (ADF&G). The catch hit a record high of 92.6 million in 2013.

Statewide harvests of all species were often below that in the 1970s.

By producing so many fish, the hatcheries have become a cornerstone of a nearly $300 million to $730 million business, according to the McDowell Group, an economic consultancy. The variation in value is based on whether the harvest is measured by what fishermen are paid or what processors bring in on their sales of the fish.

The hatchery success has not gone unnoticed elsewhere. The Norton Sound Economic Development Corporation in Northwest Alaska considered a hatchery for that area early last decade but eventually abandoned the idea.

Plenty of pinks were reported to be showing up in Norton Sound this year anyway, but there was no buyer. That could, however, always change if the supply of fish continues to grow and the bounty becomes more predictable.