California -- El Diablo's Nuclear Jellyfish

In April of 2012, an unprecedented invasion of jellyfish-like sea creatures forced a nuclear reactor on the California coast to shut down. A mysterious swarm of the gelatinous organisms, called salp, had so completely clogged screens used to filter the plant's cooling seawater, the utility company had to turn off its so-called El Diablo reactor. Salps are usually found farther out to sea, so why the creatures chose to attack the plant's filtration system en masse remains unknown.