columbia river
The Multnomah Waterfalls, in the Columbia River Gorge National Scenic Area in Multnomah Falls, Oregon on September 26, 2014. Getty Images

Thousands of rare gelatinous creatures known as pyrosomes appeared in waters from Southern California to the Gulf of Alaska this year, as reported by National Geographic.

These sea creatures were discovered to be part of a colony multi-celled animals known as zooids. Although they were identified as gelatinous, they have no relation to jellyfish. The bioluminescent creatures derive their name from the word “Pyrosoma” — Greek for “fire body.” They ranged from one to two feet and in some rare occasions, these ‘sea pickles’ grow over thirty feet in length. They are covered in small bumps and when touched they ooze pus.

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Little has been discovered about their location in the food chain except that they filter phytoplankton. Phytoplankton was reported to be the main component of the diet of shrimp-like krill. Shrimp-like krill were identified as the main component of the diet of some species of fish, whales and seabirds. Researchers also revealed pyrosomes reproduce asexually.

Some scientists identified warmer ocean climates as a driving factor in recent mass pyrosome appearances. Their presence in West Coast waters has been unusual because they are usually concentrated in the waters of the Ivory Coast, Australia, the Mediterranean Sea or Florida.

According to the National Oceanic and Atmospheric Administration (NOAA), pyrosomes reached mass oceanic status this spring.

“It’s really weird. I’ve never seen anything like it,” said Jennifer Fisher, a faculty research assistant at Oregon State University’s Hatfield Marine Science Center.

Researchers said pyrosomes pose no immediate threat to humans, but they jeopardize the fishing industry in Oregon and Alaska. Fishermen in Oregon reported pyrosomes have clogged their fishing gear and washed ashore. It took scientists five minutes to collect 60,000 pyrosomes from the Columbia River.

“It gets to a point where they’re so abundant, you can’t even fish out there,” Nancy Fitzpatrick, executive director of the Oregon Salmon Commission, said Monday. “You have to pick up your gear and move elsewhere,” she said, as reported by Reuters Tuesday.

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In southeastern Alaska, pyrosome concentration caused some fishermen to put their expeditions on pause. Sitka (Alaska) fishermen stopped fishing for salmon due to pyrosome density in Alaskan waters, according to the Smithsonian.

“We just don’t know what the long-term implications are,” said NOAA scientist Keith Sakuma.

Researchers expressed uncertainty at the rate of pyrosome reproduction and how they could disturb the aquatic food distribution in the future. They have shown concern that the increasing rates of pyrosomes may be using oxygen that other ocean marine life needs to survive.

“They just got here and have been flourishing — just super abundant. But that’s the weird thing: Why here? Why now?” said Fisher.