Planet Earth

Meet the Doomsday Fish that Strikes Fear in the Hearts of Sailors

Despite its ominous reputation and centuries of superstition, the mysterious oarfish is actually a rare and surprisingly beautiful sight for anyone lucky enough to see it.

By Stephen C. GeorgeJun 18, 2024 8:00 AM
Oarfish (Regalecus russelii) mystery animal head close up
(Credit: Pavaphon Supanantananont/Shutterstock)


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For hundreds of years, mariners and fishermen knew this sea creature as a herald of woe. Seeing one in the water or even washed up on shore was an omen, a warning of some impending disaster, typically a natural one, such as an earthquake or tsunami. In Japan, the creature was named “ryugu no tsukai,” a messenger from the palace of the sea god. Others dramatically dubbed it the Harbinger of Doom, or simply the Doomsday Fish. You may know it as the oarfish.

Then again, this might be your first time hearing the name. That’s because oarfish are fairly rare creatures to spot in the wild, even though they can be found in pretty much every ocean on the planet, with the exception of the coldest seas at the poles. Nevertheless, the creature is indeed elusive, which has no doubt helped maintain its aura of mystery down through the years. Here’s what we know about the oarfish. 

What Is an Oarfish?

(Credit: Sandstein CC BY-SA 3.0/Wikimedia Commons)

A few different species of oarfish exist in the world, but the one most people get excited about is the giant oarfish (Regalecus glesne). The name certainly fits: the giant oarfish is considered the longest bony fish in the world; lengths in the 20- and 30-foot range are not at all unheard of.

Unverified sightings and rumors claim that truly outsized specimens of the fish could grow more than 100 feet long. Guinness World Records doesn’t give those sightings any credence but has noted that, in the 1960s, scientists spotted an oarfish that they estimated to be about 50 feet in length — still a pretty respectable size.

Read More: 40-Foot-Long Giant Squids Dwarf Life on Land Because of Deep-Sea Gigantism

It doesn’t take much imagination to see how the oarfish got its name. Its pelvic fins have been said to resemble oars. And of course, the fish’s body itself is extremely flat, wider at the head but tapering towards the tail. Although it has a face that could break a camera, oarfish are still beautiful in their way. Those long, oarlike bodies typically shimmer in the light and sport colorful pink or red fins. Oarfish don’t swim so much as undulate, using the long fin on their backs to propel them through the water — something they can do both horizontally (like most fish) and vertically, swimming between lower and higher ocean depths with relative ease.

Read More: What Is the Rarest Fish in the World? The Devils Hole Pupfish

Are Oarfish Endangered?

(Credit: d3_plus/Shutterstock)

How many oarfish exist in the world? It’s a great question without a great answer, alas. Accurate population counts are hard to come by, but no oarfish species is considered endangered or threatened at present.

You could be forgiven for thinking otherwise, however, given how uncommon sightings of the fish are. The rarity of eyewitness accounts isn’t because there are few oarfish in existence, though; their habitat tends to be at ocean depths where humans seldom venture. Typically, oarfish live anywhere from about 650 feet to as much as 3,000 or more feet below the ocean’s surface, where they evolved to withstand the pressure of a deep-sea environment. If they’re seen near the surface, it’s usually a sign that the fish is sick or dying, or soon will be since, as a rule, they can’t survive long in shallow depths.

Read More: These 5 Species Were Almost Extinct, But Then Bounced Back

Are Oarfish Dangerous?

Sea serpent (Credit: Public domain/Wikimedia Commons

Oarfish don’t really pose any threat to humans. Although their gelatinous flesh is nothing you’d want to eat, they’re not poisonous. Oarfish aren’t particularly aggressive either. Even if they were, they don’t have a lot of muscle mass to thrash those long bodies around with any kind of injurious force.

Also, oarfish don’t have teeth. Instead, they possess structures known as gill rakes, which they use to filter-feed — swimming with their mouths open to catch small fish, crustaceans (such as krill), squids, and even jellyfish. If oarfish have a dangerous reputation, it’s mainly due to legends and folklore rather than any threatening physical or behavioral traits. 

Read More: 5 Of The Deadliest Animals Around The World

Why Are Oarfish Considered Harbingers of Doom?

(Credit: Fly_and_Dive)

While in times past their size and often stupendous length likely gave rise to many a sailor’s tales of sea serpents, the innocent oarfish is hardly a diabolical or supernatural creature. Nevertheless, its history as a harbinger of doom is well-documented, especially in Japanese folklore. There, in addition to its reputation as “ryugu no tsukai,” the messenger of an aquatic deity, the oarfish has also been linked to the legend of “jinja hime,” another servant of the sea god.

This underwater creature was said to have a snakelike body with a woman’s head. Both legendary creatures were purported to possess similar supernatural abilities, mainly in foretelling the future, especially when it came to issuing warnings and predicting disaster.

It almost goes without saying that science has established no credible link between the oarfish and any extranormal ability to predict future calamities. At present, it’s also considered highly unlikely that seismic or other natural precursors to earthquakes or tsunamis would affect the behavior of oarfish enough to drive them ashore or into shallow waters.

Still, make of this what you will: In 2010, several dead oarfish unexpectedly appeared on beaches in Japan, just months before the March 2011 earthquake that killed nearly 20,000 people and triggered an infamous nuclear accident at the Fukushima power plant. In 2017, dead or dying oarfish also washed ashore in the Philippines, mere days ahead of a 6.7 magnitude earthquake that struck the southern part of the island country.

Meanwhile, just a few months ago, in February, 2024, a living oarfish — this one more than 12 feet long, and distressingly mangled and bloody — alarmed fishermen when it was found on another beach in the Philippines. It died shortly after its discovery. Fortunately, no disaster or calamity has been linked to the incident.

So far.

Read More: These 12 Deep-Sea Creatures Are More Comical Than Creepy

Article Sources

Our writers at use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:

Before he became editor of Discover in 2012, Steve George spent more than 20 years as a writer and editor, specializing in health and medicine. He began his career at a scientific, technical and medical publisher, then moved to consumer-oriented publications, where his work has appeared in Men’s Health, Men’s Journal, Prevention, Outside and dozens of other magazines and web sites.

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