The Power of the Jellyfish

Morgan O'Rourke


November 1, 2013


In early October, in the midst of headlines about the U.S. government shutdown, a group of jellyfish initiated a shutdown of their own. In southeastern Sweden, workers were forced to close one of the reactors at the Oskarshamn nuclear power plant—which supplies 10% of the country’s power—after a massive swarm of moon jellyfish clogged the cold water intake pipes that help regulate the reactor’s temperature. Officials said that since the jellyfish had not actually gotten past the plant’s filters or into the reactor itself, there was no danger of an accident, but the reactor was shut down as a preventative measure while the blockage was cleared.

Strangely enough, this tale of jellyfish sabotage is not unique. It seems that these gelatinous creatures have a particular affinity for taking power plants offline. In fact, in 2005, a different reactor in the Oskarshamn plant had to be shut down for the same reason. Last year, it was the Diablo Canyon power plant in California that had to temporarily cease operation, just like it had to do in 2008. In 2011, plants in Florida, Scotland, Japan and Israel were victims of the jellyfish menace. More than 100 tons of jellyfish were removed from the intake filters at the plant in Hadera, Israel alone. In 2006, jellyfish took out the USS Ronald Reagan after they were sucked into the aircraft carrier’s nuclear reactor cooling system while it was docked in Brisbane, Australia. And in 1999, some 50 dump trucks’ worth of jellyfish clogged the intakes at a coal-fired power plant in the Philippines, causing a power failure that affected 40 million people.

Jellyfish plague the fishing industry as well. In 2007, jellyfish wiped out the only salmon farm in Northern Ireland when they flooded into the salmon cages and killed some 100,000 fish. In the Sea of Japan, giant Nomura’s jellyfish, measuring up to six feet in diameter and weighing 450 pounds, are regularly responsible for destroying fisherman’s nets, poisoning fish and even capsizing the occasional fishing trawler.

According to some experts, the prevalence of these swarms—known as jellyfish blooms—is cyclical, and we may simply be at a more active part of the cycle. Others believe, however, that jellyfish populations are on the rise and that humans are only making the problem worse. Changing ocean conditions, such as warmer temperatures and the overfishing of predators, have been thought to lead to an increase in jellyfish populations, while increasing ocean acidification from carbon dioxide emissions tends to have less of an effect on jellyfish than it does other sea creatures, as jellyfish require less oxygen to survive. Either way, if jellyfish numbers are on the rise, humans are going to have to devise new ways to deal with them.

Scientists are doing their best. Researchers from Japan’s Hiroshima University are trying to create a method to predict jellyfish blooms in advance, while Korean scientists have created robots known as the Jellyfish Elimination Robotic Swarm (JEROS) that seek out blooms and shred them with mounted propellers. The problem is, since virtually transparent jellyfish are so hard to detect via camera or satellite, none of these methods are foolproof. Relying on debris filters, safety protocols and sheer luck of the draw—as many power plants are forced to do—may be the only real solution.

But even if we figure out how to keep jellyfish away from our coastal power plants, we’ll still have to deal with the squirrels, birds and other animals that seem equally determined to knock out our inland power plants. A recent New York Times article reported that squirrels caused 50 power outages in 24 states over a three-month period this summer by coming into contact with transformers and power lines. And, according to reporter Jon Mooallem, these were only the incidents that made the news. Some utility companies have blamed up to 20% of their power outages on wild animals.

Evidently, regardless of whether it’s by land or by sea, if nature decides that it’s lights out, well, then it’s lights out. Since there’s no arguing with Mother Nature, we’ll just have to adapt to our new animal overlords—and hope they don’t end up ruling with an iron tentacle.

Morgan O’Rourke is editor in chief of Risk Management and director of publications for the Risk & Insurance Management Society, Inc. (RIMS)