Climbing Ocean Temperature Forces Snow Crabs into Starvation: NOAA Reveals Alarming Trend

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The mysterious disappearance of billions of snow crabs from Alaska’s maritime waters has been perceived as a grave environmental enigma until recently, when scientists delivered a disheartening revelation. Attributing the disappearance to the elevation in oceanic temperatures, researchers claim the heat likely induced the crabs into a state of starvation.

This distressing discovery has arrived on the heels of the Alaska Department of Fish and Game’s cancellation of the snow crab harvest season for the successive year. The decision was impelled by the alarmingly low count of crabs braving the chilling and formidable waters of the Bering Sea, a traditional habitat for the species.


In a study released on Thursday by the National Oceanic and Atmospheric Administration’s (NOAA) scientific community, compelling evidence pointed towards a correlation between marine heat waves recently hitting the eastern Bering Sea and the abrupt vanishing of snow crabs. The worrying trend caught the researchers’ attention through surveys held in 2021.

Cody Szuwalski, NOAA’s lead author and fishery biologist for this study, recalled his disbelief on first analyzing the 2021 data. Expectations hovered around a miscalculation in the survey or the possibility of recovery in the subsequent year’s data. The data in 2022, however, only solidified the unfortunate reality of the lengthy battle that lay ahead for the snow crab population’s revival.

OOMarked by the first-ever year of closure for the US snow crab fishery in Alaska, 2022 signaled a sense of desolation within the catching community. Although overfishing was initially suspected, the term, in its technical sense, only initiated conservation measures yet fell short of being the root cause behind the collapse.

The comprehensive study aimed to determine the factors triggering the snow crab’s disappearance beginning in 2020. It simmered down to two possibilities – the snow crabs had either relocated or had perished. As researchers looked towards the deeper recesses of the ocean, the northern extremities of the Bering Sea, or even westwards towards Russian waters, they ultimately dismissed the possibility of relocation. Instead, a mortality event driven by changing temperature and population density emerged as the primary cause of the population drop.

Snow crabs, essentially cold-water dwellers, function optimally in waters maintaining temperatures below 2 degrees Celsius. The harsh reality of the climate crisis has seen temperatures around the Arctic region escalating quadruple times faster than the rest of the planet, inciting a rapid reduction in sea ice. Particularly in Alaska’s Bering Sea, this development has intensified global warming. Add to this the drastic increase in the metabolic rates of the snow crabs, creating insatiable hunger due to warming of oceanic waters.

The year 2018 signaled the onset of a two-year marine heat wave in the region. This period witnessed the snow crabs’ food-requiring energy potentially quadrupling from the previous year due to the consequent disturbance in the Bering Sea’s food chain. With their caloric intake demands exceeding their foraging capabilities, snow crabs bore the brunt of the crisis.

As the heat wave broke natural barriers, other marine species like the Pacific cod exploited the opportunity to prey upon the struggling crab population. However, as the heat wave rescinded, the ecological system somewhat regained its balance. But with losses far exceeding their rate of recovery, snow crabs continue to face their long journey to survival on a precipitous path.

The calamity befalling Alaska’s crabs provides stark evidence of the rapidly ascending climate crisis and its impact on livelihoods. Szuwalski claimed the writing was always on the wall, though the drastic change accelerated well beyond anticipation. While a northward movement is expected for the snow crab population facilitated by the receding ice, the eastern Bering Sea is unlikely to serve as their home going forward, forecasted Szuwalski.