The crabs are coming for you, Panama, and they're coming by the thousands. As the Guardian reported, the "underwater mountain" known as the Hannibal Bank Seamount was recently teeming with red crabs, also known as tuna crabs, "in a way never before recorded."
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"We just saw this cloud but had no idea what was causing it," Jesús Pineda, a scientist at the Woods Hole Oceanographic Institution and one of the divers who discovered the crab swarm off the Panamanian coast, told the Guardian. "At first, we thought they were biogenic rocks or structures. Once we saw them moving, swarming like insects, we couldn't believe it."
Pineda added that his team had "no idea why they [the crabs] might be doing this," because this is highly unusual crustacean behavior, especially for the Pleuroncodes planipes, which typically sticks to southern California and Mexico. The researchers published a paper on the matter, noting that "the crabs were patchily distributed," but that "crab density peaked in the middle of the patch, a density structure similar to that of swarming insects."
Similar, perhaps, to a plague of locusts?
According to the Guardian, the crabs convened some 1,200 feet under the waves in low-oxygen hypoxic water, possibly hiding from the predatory tuna that give the crabs one of their names. The crabs themselves are scavengers, so it makes sense that they're scuttling over the sea floor. But in such robust swarms? Spooky.
It won't be long now...