Billions of Snow Crabs Disappeared from the Bering Sea, Alaska, in 2022 Due to Warming Waters Leading to Starvation.
In 2022, fishermen and scientists were deeply concerned as billions of snow crabs vanished from the Bering Sea, Alaska. This tragedy appears to be just one of the consequences of a significant transformation occurring in the region, according to a newly published study by the National Oceanic and Atmospheric Administration (NOAA) on August 21.
Shells and carcasses of snow crabs on a table at the Alaska Fisheries Science Center in Kodiak, Alaska. (Photo: CNN/Joshua A. Bickel).
The study indicates that warming waters and lack of ice in the southeastern Bering Sea—conditions typically seen in the sub-Arctic region—are occurring at rates approximately 200 times higher than before humans began burning fossil fuels to heat the planet.
The changes in the Bering Sea ecosystem have even occurred within a single human lifetime, according to the study’s lead author, Michael Litzow, director of NOAA’s Kodiak Laboratory in Alaska. He noted that there will be more very warm years ahead, while conditions typical of the Arctic—such as freezing temperatures and abundant ice—will become increasingly rare.
Snow crabs (Chionoecetes opilio) thrive in cold Arctic waters, particularly in areas where water temperatures are below 2 degrees Celsius, although they can survive in warmer waters up to about 12 degrees Celsius. A marine heatwave that occurred from 2018 to 2019 was particularly devastating for them. Warmer waters accelerated the crabs’ metabolism, but there was not enough food available to sustain them. As a result, billions of crabs starved, causing significant damage to Alaska’s seafood industry in the following years. The snow crab industry has a substantial commercial value, reaching up to $227 million annually.
The decline of Alaska’s snow crabs signals a greater shift in the Arctic ecosystem, as the ocean warms and sea ice disappears. The waters around Alaska are becoming less hospitable for various marine species, including red king crabs and sea lions.
Warmer waters in the Bering Sea also introduce new species that threaten those that have long existed in the cold waters, such as snow crabs. Typically, the ocean has a “thermal barrier” preventing species like Pacific cod from accessing the extremely cold habitats of crabs. However, during the heatwave of 2018-2019, Pacific cod entered these unusually warm waters and preyed on snow crabs.
The Arctic region is warming four times faster than the rest of the planet. Litzow described the current situation in the Bering Sea as a harbinger of what is to come. “We all need to recognize the impacts of climate change. We pay a lot of attention to this for good reason—people’s livelihoods depend on it,” he said.
