Conservation Workers Discover 13-Foot Oarfish Washed Up on Beach

— -- A walk on the beach turned into a surprising discovery for two conservation staffers in California.

A “fairly rare” 13-foot oarfish washed up on the shores of Catalina Island on Monday where staffers from the Catalina Island Conservancy stumbled upon it, the organization said.

Oarfish usually live in the open ocean anywhere from 500 to 3,000 feet deep, which makes seeing them a relatively rare occurrence, Matt McClain, the conservancy's director of marketing and communication, told ABC News today.

Most of what scientists know about the fish, McClain said, comes from the ones that wash up on beaches around the world.

“Researchers have found some washed ashore in San Diego and New Zealand, too,” said McClain. “They’re definitely not common to see but also not super-duper rare."

Monday’s discovery comes just 18 months after Catalina Island had an 18-foot long oarfish wash onto its shores.

The conservation staffers found the fish near Emerald Bay while out surveying bird breeding.

The fish was turned over to researchers, who performed a necropsy –- the animal version of an autopsy -- and sent the remains to be further researched at Cal State Fullerton, McClain said. The scientists want to check whether other factors were involved in the fish's death, he added.

The conservancy said ancient mariners sometimes mistook oarfish for sea serpents because of their “long, slender, silvery bodies.”

And Samuel Taylor Coleridge, in his 1834 poem "The Rime of the Ancient Mariner," wrote of "water-snakes" whose beauty spurred the Ancient Mariner to pray -- thus causing the albatross to slip from his neck.