Four of the plant’s reactors shut down after swarms of jellyfish clogged its pumping stations. It isn’t the first time the creatures have thwarted nuclear plants.

Four reactors at France’s Gravelines nuclear power plant were shut down late Sunday due to a swarm of jellyfish in the cooling systems, operator EDF said on Monday, likely due to rising water temperatures because of global warming.

Jellyfish swarms forced a shutdown of France's largest nuclear facility at Gravelines, impacting 900-megawatt reactors but posing no safety risks to staff.