• The verdict is in on that sea monster video: It's a jellyfish

    Experts say the "Cascade Creature" is a jellyfish that's been turned inside-out.

    By Alan Boyle, Science Editor, NBC News




    Marine biologists say the spooky "Cascade Creature" seen drifting through the deep sea in a viral video isn't a whale placenta, a parachute, a plastic bag or an alien visitor: It's a type of jellyfish known as a Deepstaria enigmatica.

    The video, which was apparently captured by a remotely operated vehicle near an underwater drilling site, caused a bit of a stir over the past couple of weeks among weird-science fans. Now it looks as if the truth is out there, thanks to assessments from experts such as Steven Haddock at the Monterey Bay Aquarium Research Institute and Craig McClain at the National Evolutionary Synthesis Center.

    "This bag-like jelly is not that rare, but is large, so rarely seen intact," Haddock and his colleagues write on the JellyWatch Facebook page. "In the video, the swirling from the sub makes the medusa appear to undulate, and it even turns inside-out." They provide a helpful picture of a more typical specimen.

    McClain is even more helpful in his posting at Deep Sea News. He provides citations on previous sightings of the beast, including explanations for the jellyfish's weirdly collapsed shape. And he shows through photographs and drawings that the strange appendage and whitish lumps seen in the video are D. enigmatica's gonads. TMI, Craig ... TMI.

    For a third opinion, look no further than Australia's Nine News, which quotes Daniel Bucher, a marine biologist at Southern Cross University, as saying that the gonads were the giveaway.

    Now that we've settled that, bring on the next sea monster.

    More sea monsters:

    Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

  • Diablo Canyon nuclear plant in California knocked offline by jellyfish-like creature called salp

    Diablo Canyon Power Plant / AP

    This photo provided by the Diablo Canyon Power Plant on Friday shows salp, a gelatinous sea creature, at a nuclear reactor intake structure.

    By James Eng, NBC News

    In Japan, it was a monstrous earthquake and tsunami that brought down the Fukushima nuclear plant. In California, it’s a tiny, jellyfish-like sea creature called salp that’s causing problems at the Diablo Canyon atomic plant.

    An invasion of salp has prompted Pacific Gas and Electric Co. to temporarily shut down a nuclear reactor at Diablo Canyon, in Avila Beach, San Luisa Obispo County, on the central California coast.

    A giant swarm of the transluscent barrel-shaped organisms this week clogged intake screens that are used to keep marine life out of the seawater that is used as a coolant for the nuclear plant.


    On Wednesday, PG&E officials reduced power output at the Unit 2 reactor, then decided to shut it down altogether “until conditions improve at the intake structure.” The plant’s other reactor, Unit 1, had already been shut down earlier in the week for a planned refueling and maintenance outage.

    “Safety being the number one priority, there was such an influx of salp and you need ocean water to cool the reactors,” PG&E spokesman Tom Cuddy told msnbc.com on Friday. “At that point we made a conservative decision to safely shut down the unit.”

    PG&E owns and operates the Diablo Canyon Power Plant, whose two reactors together produce approximately 2,300 net megawatts of electricity – enough to serve nearly 3 million northern and central California homes.

    Cuddy said he wasn’t sure when the Unit 1 reactor would come back online.

    “We’ll turn the unit on to full power when it’s safe to do so – when the salps leave,” he said. “The bottom line is we’re taking a methodical and conservative approach.”

    Lara Uselding, a spokeswoman for the Nuclear Regulatory Commission, the federal agency that oversees reactor safety and security, said the plant is not in any danger.

    “It’s not a normal operation condition, but the plant is safe and all the systems operated as designed,” she said.

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    Salps are tiny, gelatinous organisms that move by contracting, thus pumping water throughout their bodies. They can reproduce and multiply quickly.

    Though salps look a bit like jellyfish, they are actually more closely related to organisms that have backbones. They typically grow to 1 or 2 inches long and usually do not appear at the coast, says Larry Madin, a salp expert and research director at Woods Hole Oceanographic Institution in Massachusetts.

    “They’re typically more of an offshore living organism," Madin says. He surmises that the swarm at Diablo may have been carried in on currents blown by wind.

    But Steve Haddock, a scientist with the Monterey Bay Aquarium Research Institute in Moss Landing, Calif., said salps have been blooming in high numbers along the California coast since at least December. Several sightings have been reported to JellyWatch, a website Haddock runs to track sightings of jellyfish and other marine organisms.

    Other than clogging the cooling system filters of a nuclear plant, the organisms pose no danger, says Bruce Robison, senior scientist at the Monterey Bay Aquarium Research Institute. They don’t sting, they don’t have teeth and they’re not poisonous.

    Salps passively feed off tiny organic particles in the water and can reproduce sexually or asexually. “They can have their population size expand tremendously within a short period of time, which makes them very abundant. In a small space, they can take up all the space,” Robison says.

    Madin said the slimy swarm at Diablo would probably go away in a few days, carried off by currents. Or, says Robison, they’ll quickly die off when their food supply runs out.

    So the best bet, experts say, is for nuclear officials to just wait it out in the short term. "Long term, perhaps if their intakes were a bit deeper, it would not be a problem," Haddock said.

    Despite the reactor outage, California is not expected to experience any electricity shortages because it has ample reserves, said Stephanie McCorkle, spokeswoman California ISO, which operates the state's power grid and wholesale markets.

    It’s not the first time that sea creatures have interfered with nuclear plant activity.

    In 2008, a swarm of jellyfish led to a sharp decrease in power generation at Diablo Canyon, according to the Los Angeles Times.  Similar jellyfish problems have cropped up at nuclear plants in the U.S., Japan, Israel and Scotland over the years, the newspaper said.

    “It happens. It’s something you would expect along the coast,” Uselding said.

    Madin said this is the first time he’s heard of salps interfering with the operation of a nuclear plant.

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