Climate Change Decimated Alaska's Snow Crab Population

A few years ago, scientists and fisherman alike noticed something peculiar and disquieting in the waters off the coast of Alaska: there were far fewer snow crabs there than what was expected. Initial reports, as The Guardian‘s Erum Salam noted, ascribed the change to overfishing. Given that snow crabs are very tasty, this explanation seemed plausible — even as the lack of crabs in Alaska led to the 2022 snow crab season there being canceled.

Now, a group of scientists affiliated with the National Oceanic and Atmospheric Administration have come up with a different explanation, and it’s one that’s all too familiar in 2023: namely, climate change. The paper, titled “The collapse of eastern Bering Sea snow crab,” explores the disappearance of — no, this number is not a typo — 10 billion snow crabs from the Bering Sea between 2018 and 2021.

The paper makes a convincing case that the substantial drop in snow crab population was not due to, in the words of its authors, “indices of trawling, predation, cannibalism, or disease.”

Instead, as the paper’s authors write, their explanation “[links] this collapse to a marine heatwave in the eastern Bering Sea during 2018 and 2019.” The ensuing deaths of snow crabs, they continue, were “one of the largest reported losses of motile marine macrofauna to marine heatwaves globally.”

Why Aren’t We Talking More About Flooding in Alaska?

Floods recently destroyed several buildings in Juneau

As the scientists note, there is some precedent for this kind of event: a similar decline in the cod population around 2016 was also due to warmer water temperatures. Their conclusions this time around are sobering, with the observation that “starvation likely played a role in the disappearance of more than 10 billion snow crab.” And it begs the question: what will be the next species of marine wildlife to be decimated by rising temperatures?