Billions of Crabs Suddenly Vanished, Likely Due to Climate Change, Study Says
Alaska’s snow crab industry faced an unexpected and devastating halt in 2022 as billions of crabs seemingly disappeared. New research from the National Oceanic and Atmospheric Administration (NOAA) attributes this alarming phenomenon primarily to human-induced climate change, which has led to a significant shift in the ecological balance of the region.
The Rapid Disappearance of Snow Crabs
The study highlights that a process called “borealization,” which involves a transition from Arctic to sub-Arctic ecosystem conditions, is 98% likely driven by human activities. This shift resulted in the abrupt disappearance of nearly 10 billion crabs between 2018 and 2021, causing the industry’s value to plummet from $227 million to zero. A particularly concerning factor was the heatwave in the Bering Sea, which raised water temperatures. This increase accelerated the crabs’ metabolisms, leading to a higher demand for food that the ecosystem could not supply, ultimately resulting in mass starvation.
Mike Litzow, the lead author of the study and director of the Alaska Fisheries Science Center’s Kodiak Lab, warned that the conditions in the southeastern Bering Sea favorable for snow crabs are likely to continue declining. This presents a grim outlook for the crabbing industry if no significant actions are taken.
Impact on the Ecosystem and Industry
The sudden decline in snow crab populations has puzzled both scientists and fishermen. Previously abundant, the crabs’ rapid decrease caught everyone off guard. Between 2018 and 2019, a combination of rising water temperatures and loss of sea ice created inhospitable conditions for the crabs. Although the temperature changes did not directly harm the crabs, they led to a scarcity of food, which was detrimental to their survival.
To understand these changes, researchers examined various factors, including ice cover, ocean bottom temperatures, algal blooms, and the composition of Arctic marine communities over a 50-year period. Their findings revealed that boreal conditions are now about 200 times more likely than before the industrial revolution due to global warming caused by human activities.
Future Prospects for the Crabbing Industry
The Alaska Department of Fish and Game faced a difficult decision in 2022, choosing to close the snow crab fishery for the season. With minimal signs of recovery, the closure extended into the following year. Alaska Governor Mike Dunleavy has since sought federal assistance, requesting U.S. Secretary of Commerce Gina Raimondo to declare a fishery resource disaster for the Bering Sea snow crab fishery for the 2023-24 season.
Although the situation remains challenging, the study published in the journal Nature offers some hope. Cooler temperatures returned in 2022, more closely resembling historical conditions, providing a glimmer of hope for the snow crab population.
Adapting to a Changing Environment
The study underscores the urgent need for the fishing industry to brace for the potential “complete loss of Arctic characteristics in traditional fishing grounds.” The rapid changes observed emphasize the necessity for proactive measures in adapting to a warming climate.
As Litzow stated, “It’s really important that fishermen, scientists, communities, and resource managers recognize that one of the most productive marine ecosystems in the world is changing – faster than anyone expected. The time to act is now to think about how we are all going to adapt.”
The study serves as a crucial reminder that the impacts of climate change are not just theoretical predictions for the future but are occurring now, affecting livelihoods, economies, and ecosystems. Immediate action and adaptation strategies are essential to mitigate further damage and ensure the sustainability of vital marine resources.
