Baffled beachgoers have stumbled upon millions of mysterious sea creatures that have washed up on Oregon shores in recent days.
The bumpy, slimy and translucent marine invertebrates commonly known as “sea pickles” have taken over beaches.
The pickle-shaped creatures, which are not edible, are actually called pyrosomes and are made up of millions of individual organisms.
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The asexual organisms clone themselves to create massive colonies, with some individual formations reaching up to 18 metres in length.
Pyrosomes typically live in deeper tropical waters, which has scientists concerned by their sudden appearance in the U.S. northwest.
“They’re normally in warmer waters, but our waters here on the coast have warmed up quite a bit,” Jim Young, a retired marine biologist from the Pacific Northwest National Laboratory, told KGW-TV.
“Sea pickles” stranded on land are relatively harmless, but massive concentrations of the organisms under water can have a greater impact.
“If there’s enough of these and they sink to the bottom, it could maybe cause a dead zone,” Young said.
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If these colonies experience a mass die off, their decomposing cells can suck oxygen from the water, killing other organisms living on the ocean’s floor.
Colonies of pyrosomes caused issues off the Pacific coast last summer, as fishermen as far north as Alaska reported tens of thousands of the organisms becoming caught in nets and on hooks.
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In October, researchers at Oregon State University reported one of these dead zones was responsible for the mass killing of crabs off the Oregon coast.
“It’s one of the worst that we’ve seen,” OSU marine ecologist Francis Chan told KGW.
According to Chan, the lack of oxygen suffocated the crabs and forced fish into areas they don’t normally live in.
Researchers are hoping choppier seas caused by winter storms will be enough to disperse any remaining dead zones but are concerned the issues may become more common as ocean temperatures rise.