Despite The Nation magazine this month suggesting Alaska salmon in peril, the Alaska Department of Fish and Game says consumers need not worry about eating wild-caught fish from the 49th state.
Salmon runs in Alaska remain large, healthy and professionally managed, according to the state agency, and they are certified sustainable by the Marine Stewardship Council, a global fisheries monitoring group.
The Nation in a cover story suggested Alaska is down to “The Last Salmon” and declared that “Bristol Bay is one of Alaska’s few healthy salmon habitats.”
Alaska Commissioner of Fish and Game Doug Vincent-Lang pushed back against the latter claim in particular on Thursday.
“Alaska abounds in healthy habitat, which is evident from our abundance of numerous fish stocks and wildlife populations,” he said in a statement. “This the result of a robust and adaptive regulatory program that Alaska has in place that ensures sustainability of our fish and wildlife.
“As a result, on a sustained yield basis, we’re producing and harvesting more fish and game than ever before and are constitutionally mandated to keep that going for all future generations of Alaskans. The state’s right to manage was hard fought for at Statehood and it has paid off for all Alaskans.”
Aside from modern fish and wildlife management, there is no doubt the state’s fish and wildlife resources have also benefitted from a small human population and almost no development. The state has no major dams, less than half of a percent of the landmass tied up in agriculture, and a tiny timber industry. Those are the main activities blamed for degrading freshwater salmon habitat in British Columbia, Canada; Washington state, Oregon and California.
Real salmon struggles
Salmon runs in the former three areas, and especially in Canada’s Fraser River, are this year struggling but California is seeing an unusual bounty of the fish. “California Is Overflowing with Salmon,” the Wall Street Journal reported at the end of August.
The California situation would appear to lend some credence to a paper written by a group of Canadian scientists suggesting the real issue with salmon survival is in the ocean where the fish spend most of their lives. That paper, which challenges some long-held views on salmon production, has been tied up in peer review for more than a year.
The Nation story parrots the view that freshwater habitat changes make salmon vulnerable to climate change along the West Coast, although there is no evidence to indicate Alaska habitat has been “increasingly challenged by climate change” as the Nation story asserts.
To date, if climate change has done anything to Alaska salmon, it has boosted the fish. Alaska salmon numbers have steadily increased as the North Pacific Ocean has warmed. More than 203 million salmon were harvested in Alaska this year, according to preliminary numbers from Fish and Game.
That ranks the harvest as the eighth largest in an Alaska fishing history that dates back more than 120 years. The largest harvest on record was more than 280 million in 2013. Four of the eight largest harvests in history have come this decade, and all harvests over 200 million have come in the last 25 years.
Most telling are the increases in average, annual harvests in the decades since the end of the cold water years in the North Pacific Ocean in the 1970s. From a ’70s era harvest of 48.3 million salmon per year on average, Alaska catches have risen to:
- 122.4 million per year on average in the ’80s.
- 157.5 million per year on average in the ’90s
- 167.4 million per year on average in the 2000s.
- And approximately 180 million per year on average for the 2010s.
Fisheries scientists fear that as the planet continues to warm salmon production in the North Pacific could begin to decline. Even barring climate change, some say, it is unrealistic to believe annual harvests can continue to increase at the current pace, and it is obvious the rate of increase has been slowing from more than 150 percent in the 1980s to about 8 percent between this decade and the previous.
Climate models predict Alaska could warm anywhere from two degrees to 20 degrees by 2100, according to the National Oceanic an Atmospheric Administration. The maximum warming would boost the average temperature in southern Alaska into the mid-60s. That is near the temperature of California today.
The models, however, predict increases in precipitation, which could help to buffer any warming effects on salmon. But the picture is complex. Many Alaska salmon rivers are glacially influenced and the disappearance of glaciers would significantly affect instream flows.
Almost anything could happen in the future, but in the here and now, there is no sign of downturns in Alaska salmon runs. The north Pacific, according to a widely accepted study by scientists Greg Ruggerone and James Irvive, today holds more salmon than ever.
The Nation story hinted that the change in this trend might have begun with the unusually hot, dry summer of 2019 and the death of some salmon from heat stress in warm water. But such dieoffs have happened in unusually warm, dry summers for decades.
Risks of salmon deaths go up any time returns are large, as they were this year, and stream flows are low. The heat reduces the amount of oxygen water can hold, and if there are too many fish competing for air in oxygen-short water some fish suffocate.
“During the summer drought in the Southeastern part of Alaska,” the U.S. Geological Survey reported in 1991, “25,000 salmon died in eight streams due to low flows, warm water and lack of oxygen. Six of the eight fish kills were reported on Prince of Wales Island near Ketchikan.”
Lack of oxygen is the usual killer, but The Nation, echoing other media reports, pointed to a new form of death in observing that “hundreds of salmon perished in the lower Kuskokwim River, where water temperatures reached the 70s, before they’d had a chance to spawn. Scientists theorized the fish died from heart attacks caused by the heat.”
There is no evidence hundreds of salmon died from heart attacks, and there are no “scientists” (plural) theorizing deaths due to heart attacks. There was one state fisheries biologist who says his comments about salmon deaths were mischaracterized, and “it just never went away after the first misquote,” Fish and Game spokesman Rick Green said Thursday.
“I’ve been throwing water on that fire all year after the 8o, dead, prespawn chum in 160 river-miles started being characterized as a ‘massive die-off.'”
Scientists don’t know positively what killed those fish or others in the Koyukuk River, but the belief is lower oxygen levels in the water played a role.
“The biologist from Bethel regrets those remarks regarding heart attacks,” Ted Meyers, the state’s chief fishery pathologist said in an email. “Our and other scientists agreed that the fish mortalities were indeed caused by high water temperatures causing low dissolved oxygen when so many fish were present in low water flows. This scenario played out in several different watersheds.”
The salmon might have suffocated after they used up all the oxygen in the water, or they might have already been compromised by parasites or illnesses that weakened them enough that they could not survive the heat stress and low though not normally fatal oxygen declines.
Fish suffocating is an old story that goes back decades not only in Alaska but all across North America. After the drought of the 1930s, the U.S. Bureau of Fisheries declared, “eight states report a very serious situation with a loss of fish reaching disastrous proportions….
“There is a very general agreement that in addition to the loss of fish by stranding and suffocation, an additional drain will arise from the vulnerability of the fish in restricted pools and lowered lakes….”
Almost 90 years later, however, in the age of global warming, one summer’s drought leads to a declaration Alaska is down to its “last salmon.”