A mysterious disease is killing thousands of starfish off the coast of Vancouver — basically pulverizing them as they lie in the ocean. It’s probably due to overpopulation, but nobody really knows what the hell is going on.

Overpopulation is certainly making things messier. Sunflower sea stars have exploded in Vancouver; in places they were “stacked several stars deep,” says the Canadian Press. And when the disease struck, those stacks of starfish began “disintegrating where they sat on the ocean floor.”

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But, says the CP, it’s hard to say anything for sure:

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The aquarium has dubbed the epidemic Sea Star Wasting Syndrome.

Aquarium staff don’t know the cause because they have had trouble gathering specimens for testing, as starfish that looked healthy in the ocean turned up as goo at the lab.

It’s terrifying, and also a great idea for a horror movie. Forget global epidemics that turn you into a zombie: How much more scary is it if you catch a disease and then just slowly melt?

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