A nuclear power plant in California had to be closed down after an invasion of jellyfish-like marine organisms called salp.
Workers at the Diablo Canyon plant discovered hoards of the salp clinging to the structure, clogging the traveling screens in the intake structure, which are meant to keep marine life out and to keep the unit cool.
There are two units at the plant. Unit 1 had already been shut down due to refueling and maintenance work, which is expected to take several weeks. Now that the salps have caused Unit 2 to also shut down, the plant has had to cease all production until the creatures move on and the filters are clear.
Salps are similar in appearance to jellyfish, due to their simple body form and planktonic behaviour, but they are structurally most closely related to vertebrates. They feed on phytoplankton.
Salps are common in equatorial, temperate and cold seas where they can be seen at the surface, sometimes in long, stringy colonies, like those shown in the picture above.
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