A group of researchers were out for a swim in San Diego recently when they encountered an oarfish, an "incredibly rare" creature whose appearance is an omen of impending disaster. Specifically, earthquakes, which are known to rattle the region frequently.

The researchers saw the dead sea serpent while they were snorkeling and kayaking at La Jolla Cove in San Diego, Lauren Fimbres Wood, a spokesperson for the Scripps Institution of Oceanography at the University of California, told USA TODAY on Friday.

They contacted the National Oceanic and Atmospheric Administration and a Scripps' Marine Vertebrate collection manager, coordinating with lifeguards at the beach to help get the "large and heavy fish" transported to a nearby NOAA facility, Fimbres Wood said. And take plenty of photos of the rare sight, of course.

The deep-sea fish has only been seen in the state 20 times since 1901, making the find especially notable for the group. And thanks to their work, scientists will be able to further study this mysterious species, Fimbres Wood said.

It's set to become part of Scripps’ marine vertebrate collection, one of the largest collections of deep-sea fish in the world, Fimbres Wood said.

Photos: Scientists document 'rare' find while out for a swim

It's not clear why the "mysterious species" was spotted above the surface, but it did provide an excellent opportunity for Emily Miller, Natalia Erazo, Alejandro Cano-Lasso Carretero, Gabriella Costa Machado da Cruz, Michael Wang and Luis Erazo to snap a couple pictures with the oarfish before it was turned over.

NOAA Southwest Fisheries Science Center and Scripps scientists worked to learn a little more about the specimen collected, conducting a necropsy on Friday to determine the cause of death. Fimbres Wood could not be reached for comment Monday afternoon to discuss the details of the necropsy.

What makes the sight of the oarfish particularly interesting is that they typically live in the deep sea, dwelling anywhere between 700 and 3,280 feet below the surface, USA TODAY reported. They rarely come up to the surface without a reason.

Hiroyuki Motomura, a professor of ichthyology at Kagoshima University, told the New York Post, that he believes the fish nicknamed "messenger from the sea god’s palace" only "rise to the surface when their physical condition is poor, rising on water currents, which is why they are so often dead when they are found."

And any connection between the fish and any impending earthquakes has yet to be scientifically proven, Motomura shared with The Post.

Here's a look at the oarfish discovery in pictures:

Contributing: James Powel; USA TODAY