text: Huge and unexplained bloom has fishers racing to save their nets, and scientists hurrying to study the rare animal 
   
   A rare, tiny marine creature known as the “unicorn of the sea” has swarmed in its millions on the west coast of America, ruining fishermen’s nets and baffling scientists who are scrambling to find out more about them. 
   
   Fishers along the west coast have told researchers that in some places they are unable to catch anything because the pyrosome clusters are so dense and tightly packed. Their hooks, when pulled from the ocean, wriggle with the odd-looking creatures, which are sometimes referred to as “sea pickles” or “fire bodies”. 
   
   The distinctive animals – which are only a few millimetres long but gather in huge colonies – have washed up on popular beaches, bemusing local residents. 
   
   
   
   Olivia Blondheim, a graduate student at the University of Oregon who is part of a new research team set up to study the bloom, said: “Right now we are scrambling to learn as much as possible while we have the opportunity. 
   
   “If we continue to see this many, what impact will it have on the ecosystems here, and what economic impact on the fisheries? There are so many unknowns at this point, it really is a remarkable bloom.” 
   
   Ocean Networks 🇨🇦 (@Ocean_Networks) Typically found in the tropics, we're seeing huge numbers of #pyrosomes in the eastern Pacific. Read more https://t.co/pZ8aQHhc2A #ONCabyss pic.twitter.com/18RnlIJWmW 
   
   Pyrosomes are tubular, gelatinous creatures that are actually moving colonies of tiny organisms. Asexual creatures which reproduce by cloning themselves, they have long fascinated seafarers, who have been pictured swimming through the middle of pyrosomes up to 30 metres long. 
   
   Blondheim said no one knows how much surface area the pyrosome bloom covers, except that they have gathered right along the west coast in mammoth clusters. She said every time she or fisherman had seen them the swarm stretched “as far as the eye can see”. 
   
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   Usually found in warm, tropical seas far from the coastline, researchers have been astounded by the unexpected influx of pyrosomes along the west coast of America. It began in Oregon and gradually swept north up the coast, with reports of pyrosomes spotted as far north as Sitca, Alaska. 
   
   “There were reports of some pyrosomoes in 2014, and a few more in 2015 but this year there has been an unprecedented, insane amount,” says Blondheim. 
   
   This summer was the first time she saw a real-life pyrosome in her many years of marine study. Her mentor, Rick Brodeur, a research biologist at the National Oceanic and Atmospheric Administration’s north-west fisheries science center in Oregon, saw his first pyrosome only a couple of years ago, after a 30-year career in marine science. 
   
   “On one of our cruises we saw 60,000 in five minutes and they were ripping apart our nets,” said Blondheim. “They were glowing and floating on the surface, completely covering the sea” 
   
   Few marine scientists have seen pyrosomes in the flesh because during the day they stay in the depths, sometimes up to 700 metres under the surface and usually in the open sea. 
   
   
   
   Dr Lisa-ann Gershwin, a marine biology expert, said “gargantuan” blooms of traditionally tropical pyrosomes had occurred in unlikely places before, including in the sub-Antarctic. 
   
   “Because they aren’t wanted, and people really aren’t used to seeing them – they really do impact fisheries and catch a lot of attention,” she said. “In the case of these pyrosomes, I don’t think anyone is quite sure what has led to this bloom ... it is unusual. There is every possibility it is a natural phenomenon, but an abundance this gobsmackingly big also suggests there may be something behind it that is not natural in origin.” 
   
   Gershwin and Blondheim agreed it was worth exploring if the pyrosomes were expanding more quickly due to warming sea temperatures caused by climate change, but other options for the bloom included the animals’ diet changing or unusual sea currents. 
   
   “One of the things we are figuring out is have these guys been off the coast and we haven’t seen them? Are they moving inshore for a different reason?” said Blondheim. 
   
   
   
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   This feature is not available right now. Please try again later. ||||| Hilarie Sorensen/University of Oregon 
   
   Millions of tubular sea creatures called pyrosomes have taken over the Pacific Ocean in an unprecedented bloom that has scientists baffled. 
   
   These bumpy, translucent organisms look like sea cucumbers that range in size from six inches to more than two feet long. But they’re actually made up of hundreds of tiny animals knit together with tissue into a filter-feeding cylinder. 
   
   Hilarie Sorensen/University of Oregon 
   
   And they’re everywhere, filling the waters off the West Coast all the way up to Alaska, and washing up on beaches. 
   
   One research boat caught 60,000 of them in five minutes. They’re so thick in Alaska that fishermen gave up on fishing because their hooks were coming up full of pyrosomes instead of salmon. 
   
   Jennifer Fisher, a research assistant with Oregon State University’s Hatfield Marine Science Center in Newport, makes regular research trips to monitor ocean conditions. She started seeing pyrosomes in her research net in February, and a GoPro camera on the net revealed an eerie underwater habitat filled with the pickle-shaped creatures. 
   
   “Basically as far as the eye can see: pyrosomes,” she said. “We were dumbfounded.” 
   
   Pyrosomes are common in the tropics, where they can reach a length of 30 feet and often glow in the dark. That likely explains their name, which in Greek translates to “fire body.” According to Fisher, they do show up in the ocean off the Northwest from time to time – but never in these numbers. 
   
   “Why they’re here now is unknown at this point,” Fisher said. “We’ve had warm ocean conditions over the past couple years, and something has brought them here. They’re just flourishing. It’s just very unusual to find them so close to shore, so evenly distributed, and so abundant.” 
   
   It’s strange, researchers say, because the warm ocean water that has been hanging out off the West Coast since 2014 has dissipated this year. And the Pacific has had plenty of warm water events in the past without seeing massive blooms of pyrosomes. 
   
   No one knows what the effects of the bloom will be, but scientists worry that if all the creatures die off at once they could sink to the seafloor and suck up all the oxygen as they’re decomposing, creating a dead zone for marine life. 
   
   Courtesy of National Oceanic and Atmospheric Administration 
   
   Richard Brodeur, a research biologist with the National Oceanic and Atmospheric Administration, is leading an effort to collect live pyrosomes to study in his lab in Newport, Oregon. 
   
   “We’re trying to learn as much as we can about these guys,” he said. “I’ve been working for a long time, and I’ve never seen one until now. So, we’re kind of catching up. … It’s really a mystery to us why this is happening.” 
   
   He wants to look at how they feed, how they orient themselves vertically in the water, and their swimming speed. 
   
   “They’re usually in the tropics farther off-shore,” he said. “People haven’t done anything experimentally with these guys.” 
   
   Brodeur said the pyrosomes might be a lingering effect of the warm water “blob” that in 2015-16 brought in unusual marine life including a tropical sea snake and red crabs. Though water temperatures have dropped from previous years, he said, “they’re still way above normal, and we’re still getting unusual things going on.” 
   
   Fisher will continue to monitor for the pyrosomes, and she’s interested to see how long they stick around. 
   
   “They often bloom in large numbers and then conditions become unfavorable for them and they go away,” she said. “I think that’s when we might learn more about why they’re here is when they leave looking at what conditions caused them to go.”
target: – They are called "unicorns of the sea" and they are infesting the Pacific Coast, destroying fishing nets and puzzling scientists, the Guardian reports. The tiny blob-like creatures are infesting some stretches of the West Coast as far north as Alaska so badly that fishermen can't catch anything. The translucent tubular invaders are pyrosomes, and while they generally range in size from a few inches to 2 feet, they band together in huge colonies. (See video.) They rip nets and clog hooks, and wash up on beaches to the consternation of the locals. One researcher began spotting the "sea pickles" in nets in February and since then, the numbers have exploded, per Oregon Public Broadcasting. One research boat captured 60,000 within minutes. "They were glowing and floating on the surface, completely covering the sea," says University of Oregon researcher Hilarie Sorensen. The creatures—their Greek name means "fire bodies"—prefer the tropics, but even there, they haven't been seen in the "insane" numbers of this year's bloom, says Sorensen. The impact of the little cucumbers is unknown, but there is concern their massive presence could foul ecosystems. While the bloom could be a natural phenomenon, Dr. Lisa-ann Gershwin says "an abundance this gobsmackingly big" indicates something fishy may be going on. Warming seas could be a possible explainer, or perhaps changes in the marine food supply or shifting currents. (Killer whales are also tormenting Alaskan fishermen.)