This Friday Oct. 18, 2013 image provided by Mark Bussey shows an oarfish that washed up on the beach near Oceanside, Calif. This rare, snakelike oarfish measured nearly 14 feet long. According to the Catalina Island Marine Institute, oarfish can grow to more than 50 feet, making them the longest bony fish in the world. (AP Photo/Mark Bussey) MANDATORY CREDIT

LOS ANGELES, Calif. - The silvery carcasses of two giant oarfish were discovered along the Southern California coast last week, baffling scientists and gaining a growing online following who gawked at the bony, snake-like creatures.

A four-metre oarfish washed up on a beach in the San Diego County coastal city of Oceanside last Friday. Several days earlier, a snorkeller found the carcass of an 5.5-metre oarfish off Catalina Island and dragged it to shore with some help.

The rarely seen deep sea-dwelling creatures, which can grow to more than 15 metres, may be the inspiration of sea monsters found in literature and throughout history. Photos of the oarfish have circulated widely online, spurring general interest in the mysterious creature but contributing little to scientists' knowledge of the fish.

Here's a closer look at the oarfish:

HOW OFTEN DO THEY VENTURE CLOSE TO SHORE?

Oarfish beach themselves around the world. Every so often, one wanders to the Southern California coast.

In 2010, a 3.5-metre oarfish washed ashore in Malibu. The most recent stranding before last week's sightings occurred in 2011 when a four-metre oarfish was found on a beach near the Vandenberg Air Force Base, 210 kilometres northwest of Los Angeles, said Rick Feeney of the Natural History Museum of Los Angeles County.

HOW DID THE TWO OARFISH DIE?

While necropsies — the animal version of an autopsy — were done on the oarfish, the cause of death remains unknown. Scientists said the deaths may forever remain a mystery. The smaller oarfish appeared to be in good health before it died and there were no signs of shark bites.

Oarfish are thought to be poor swimmers and it's possible that the ones found last week got caught in a current that pushed them to coastal waters, marine experts said.

"If they get disoriented and into the surf zone, they'll probably have trouble manoeuvring back out to sea," said Phil Hastings, curator of the marine vertebrate collection at the Scripps Institution of Oceanography.

WHY IS SO LITTLE KNOWN ABOUT OARFISH?

Oarfish are highly evolved. They tend to remain quiet in the deep ocean, luring smaller fish toward them.

Since they're are found in tropical waters 900 metres deep, scientists don't get many opportunities to study these serpent-like creatures. The dead oarfish that float ashore don't tell the whole story. It's like trying to study deer that end up in the windshield, said Milton Love, a marine biologist at the University of California, Santa Barbara.

"You wouldn't know much about deer based on roadkill," he said.

WHAT'S NEXT?

Scientists have dissected the oarfish, preserved some tissue and organs, and planned to send samples to researchers around the world to examine.

News from © The Associated Press, 2013