Forces profound and alarming are reshaping the upper reaches of the North Pacific and Arctic oceans, breaking the food chain that supports billions of creatures and one of the world’s most important fisheries. (via latimes)
In the last five years, scientists have observed animal die-offs of unprecedented size, scope and duration in the waters of the Beaufort, Chukchi and northern Bering seas, while recording the displacement and disappearance of entire species of fish and ocean-dwelling invertebrates. The ecosystem is critical for resident seals, walruses and bears, as well as migratory gray whales, birds, sea lions and numerous other animals.
A team from the Los Angeles Times traveled to Alaska and spoke with dozens of scientists conducting field research in the Bering Sea and high Arctic to better understand these dramatic changes. Their findings suggest that this vast, near-polar ecosystem — stable for thousands for years and resilient to brief but dramatic swings in temperature — is undergoing an irreversible transition.
Whether the warming has diminished these super-cold-water species or forced them to migrate elsewhere — farther north or west, across the U.S.-Russia border, where American scientists can no longer observe them — remains unclear. But scientists say animals seem to be suffering in these more distant polar regions too, according to sporadic reports from the area.
The dramatic shifts that Giles, Boveng and others are observing have ramifications that stretch far beyond the Arctic. The Bering Sea is one of the planet’s major fishing grounds — the eastern Bering Sea, for instance, supplies more than 40% of the annual U.S. catch of fish and shellfish — and is a crucial food source for thousands of Russians and Indigenous Alaskans who rely on fish, birds’ eggs, walrus and seal for protein.
Flying along the southeastern coastline of Kodiak Island, Matthew Van Daele — wearing a safety harness tethered to the inside a U.S. Coast Guard MH-60T Jayhawk — leaned out the helicopter door, scanning the beaches below for dead whales and seals. According to Van Daele, the whale had been dead several weeks; her body was in poor shape, with little fat.
Matthew Van Daele, left, natural resources director for the Sun'aq tribe, documents the death of a gray whale with NOAA enforcement officer Joe Sekerak, right, who provides protection from bears, Sept. 2, 2021. Matthew Van Daele conducts aerial surveys of gray whales and seal lions from the U.S. Coast Guard base on Kodiak, Alaska.
In September, an emaciated young male gray whale was seen off a beach near Kodiak, behaving as though it were trying to feed, scooping material from the shallow shore bottom and filtering it through his baleen, a system many leviathans use to separate food from sand and water. While it’s always possible the current stanza is temporary and the ecosystem could reset itself, “that is unlikely,” said Rick Thoman, an Alaska climate specialist at the University of Alaska Fairbanks.Due to atmospheric warming, the world’s oceans hold so much excess heat that it’s improbable the Chukchi Sea will ever be covered again with thick, multiyear ice, he said. Nor will we see many more years where the spring ice extends across the Bering, he said.
“When we started out, we couldn’t get north into the Bering Strait area because of ice until mid-June,” said Kathy Kuletz, a bird biologist with the U.S. Fish and Wildlife Service, who has been researching the northern Bering Sea and high Arctic since 2006 and studying Alaska birds since 1978. “Even then, it wasn’t until late June that you could get into the Chukchi. And that’s certainly not been the issue ... since, let’s see, about 2015 or so.
A 2020 study published in the journal Science documented a reduction in ice extent unlike any other in the last 5,500 years: Its extent in 2018 and 2019 was 60% to 70% lower than the historical average. In an Arctic report card released just this week, federal scientists called the region’s changes “alarming and undeniable.”
Data from a Bering Sea mooring shows the average temperature throughout the water column has risen markedly in the last several years: in 2018, water temperatures were 9 degrees above the historical average.Fish processing plants line the marina in Kodiak, Sept. 4, 2021. “So we don’t fully understand all the implications of why the fish are moving in the directions and patterns that they are,” he said. But in some places — particularly the places that once harbored cold-loving fish such as Arctic cod and capelin — they are just gone.
Ice is also essential habitat for some Arctic mammals. As with gray whales, several types of ice seals — which include ringed, spotted and bearded seals — started showing up skinny or dead around the Chukchi and Bering seas in 2018, spurring a federal investigation. These Arctic-dwelling species rely on sea ice to pup, nurse and molt. Without it, they spend more time in the cold water, where they expend too much energy.
The culprit was avian cholera, a disease not previously detected in these high latitudes, and one that elsewhere rarely fells seabirds such as thick-billed murres, auklets, common eiders, northern fulmars and gulls.
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