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Fishermen and scientists were horrified when billions of crabs disappeared from the Bering Sea near Alaska in 2022. Scientists explained that it wasn't overfishing — it was likely the shockingly warm waters that put the crabs' metabolism into overdrive. starve them to death.
But they A horrible death This appears to be just one effect of a massive shift taking place in the region, scientists reported in a new study released Wednesday: Parts of the Bering Sea are literally becoming less polar.
Research by the National Oceanic and Atmospheric Administration has found that warmer, ice-free conditions in the southeastern Bering Sea — the kind of conditions found in subarctic regions — are now about 200 times more likely than they were before humans began burning greenhouse-gas-burning fossil fuels.
“The study highlights how much the Bering Sea ecosystem has already changed from what it was even during the lifetime of the snow crab hunter,” said Michael Letzo, lead author of the study and director of NOAA’s Kodiak Laboratory in Alaska.
He also points out that “we should expect more [very warm] “True Arctic conditions — cold, icy and treacherous — will be few and far between,” he said.
Snow crabs, a species of cold-water Arctic crab, thrive most in areas where water temperatures are below 2°C, although they can physically operate in waters as low as 12°C.
The marine heatwave of 2018 and 2019 was particularly deadly for the crabs. The warmer waters caused the crabs’ metabolism to increase, but there wasn’t enough food to keep up.
Billions of cancers eventually He died of hungerdevastating the Alaskan fishing industry in the years that followed.
Snow crabs are a highly commercially valuable species, worth $227 million a year, according to the study published Wednesday. The industry needs to adapt, and fast, Litzo said.
“How are we going to do business differently as this process worsens for the snow crab fishery?” he said, noting that while he was “optimistic” about a short-term recovery, as the area had been cold so far and new baby snow crabs had spawned, he cautioned that “the odds are that the conditions will continue to be bad” for years to come.
The decline of the Alaskan snow crab points to a broader shift in the Arctic ecosystem, as oceans warm and sea ice disappear. The ocean around Alaska is now inhospitable to many marine species, including red king crab and Black seaAs the experts say.
The warming Bering Sea is also opening the door to new species, threatening those that have long survived in its treacherously cold waters, such as the snow crab.
Normally, there is a thermal barrier in the ocean that prevents species like Pacific cod from reaching the crabs’ cold habitat. But during the heatwave of 2018 and 2019, Pacific cod were able to go to these warmer-than-usual waters and eat some of what was left of the snow crab population.
“We've seen shifts in species distribution and mismatches between prey and predators, which have contributed to declines in some species like Pacific cod in the Gulf of Alaska,” Robert Foy, director of the Alaska Fisheries Science Center, told CNN.
These massive ecosystem changes pose “new challenges and opportunities for fisheries science and management,” said Foy, who was not involved in the study, noting that fisheries managers are now working to integrate new technologies such as drones and artificial intelligence “to more quickly detect and respond to environmental changes and ecological responses.”
The Arctic region has It heats up four times faster. Scientists have reported that the Bering Sea is warmer than the rest of the planet. Letzo described what is happening in the Bering Sea as a “harbinger” of what is to come.
“We all need to be aware of the impacts of climate change,” he said. “We care about this issue for good reason – because people’s livelihoods depend on it.”
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