Umibōzu: The Tentacled Sea MONSTER GHOST that PREYS on Japanese Sailors 

Japan is known for many yokai-cryptid types. One such cryptid is a terrifying sea phantom that’s said to emerge from the depths of calm waters on moonlit nights. This dark, shadowy presence is said to bring upon torrential downpours, rocky waters, and stormy nights as it towers over unsuspecting sailors. Legend has it that the Umibōzu is said to ask one simple question just before attacking sailors and capsizing their ships—answer the riddle incorrectly, and the ocean might become your early grave.

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For centuries, pirates, sailors, and fishermen alike have all charted the open seas, having long relied on stars and maps to guide them to their destination. Be it searching for buried treasure, exploring new worlds, or coming back home to their families, there are many reasons why men have been drawn to the oceanic voyage. The truth is that the ocean promises adventure. And with so much opportunity on the horizon, it was hard not to contain one’s excitement. But, with the sea’svast, unpredictable waters, sometimes this adventure came with a price. Historically speaking, sailing is a risky business. Which is why navigation tools weren’t the only things men at sea relied on. 

Superstitions of the Sea

Following superstitions and heeding age-old warnings passed through generations is often what kept them alive. Some of these superstitions were simple commands like, “When rats leave a ship, follow them,” – meaning that if rats aren’t willing to stay on board, maybe that’s a sign you should jump ship too. 

There were also special requests made by captains like, “No bananas on board” – because, at the time, bananas were thought to be bad omens. In fact, sailors often feared that bananas would hide venomous spiders or snakes that would bring about misfortune while they were stranded in the middle of the ocean. 

And then there’s the more popular adage that you have probably heard before that goes: “Red sky at night, sailors delight, red sky in the morning, sailor’s warning,” that served as a constant reminder for sailors to keep an eye out on weather patterns,

No matter the catchy phrase or even seemingly strange rules, following these guidelines was imperative to their health and well-being. These men took these sayings seriously. Because no matter how skilled a sailor might be, the open sea abides by her own set of rules. And if you choose to ignore them? The depths of the ocean might just swallow you whole, which is exactly what happened to a small crew of Japanese fishermen in the 1600s. 

Beware the Umibozu

It was the early days of Japan’s Edo period. 

During this time, merchant ships sailing from port to port, carrying goods like rice and silk were quite common. Among these seafarers, fishermen held a special place in society. As they navigated uncharted territory, keeping lurking dangers at bay, fighting off treacherous thieves, and not to mention surviving the ocean’s ever-changing temperament, these men were well-respected for their craft. 

But for one small crew of Japanese fishermen? No amount of fishing skills or fending off pirates could have prepared them for their most dangerous journey.

Just as the ship started to set sail, an older woman came barreling through the crowd, waving her hands back and forth, trying to get their attention. As the captain slowly approached the woman, he asked her why she was so desperate to share with the others. After gaining her composure, she looked up right at him and said, “Beware the Umibozu, for he rises when the waters are calm and sinks ships when least expected.” 

Respectfully, the captain thanked the woman for sharing her insight and promised that he would consider her warning and share it with his crew mates. However, as he turned around and climbed aboard his ship, he silently chuckled to himself because although there were very real dangers out at sea, to him, the Umibozu was nothing more than a myth.

Legendary Tales of Dark Water Spirits

I mean, out of all the years he had been out at sea, he had never encountered such a beast. While stories had definitely been passed around of a mysterious, giant, dark harbinger of death roaming the seas, vying for the lives of fishermen, he hadn’t known anyone who actually encountered it. There had even been hushed whispers of a water demon who would torment sailors by bobbing around their ship late at night where they would nudge their ship back and forth as a way to instill fear in them, or worse, completely capsize the whole vessel. But in all his years out on the water, he had never seen even a glimpse of such a thing. He didn’t believe in Japanese Yokai or make-believe. 

But what he did believe in was mother nature. The captain knew there were dangerous things to be mindful of and that Mother Nature had a mind of her own. He knew the risks of being out on the ocean, with many of the dangers including unpredictable weather patterns, looting pirates, and unknown creatures lurking below. But this tall tale was not one of them. 

And when the other men aboard the ship asked what the older woman had said to him? He replied, “It’s just the ramblings of a superstitious elder.” With this, the men laughed alongside him and quickly got to work as they set sail.

And honestly? 

The weather couldn’t have been more perfect. The waters were clear blue, and the skies had been without a rainy cloud in sight. The men had been out for several days now and had all but forgotten the elder’s warning. And there was no sign of any real danger. This journey had been smooth sailing. In fact, this had been the captain’s most successful trip. He had never caught so many fish before and knew that by the time they got back, it would be the most lucrative trip for all of them. And in just a few days, they’d head back to the mainland with all their fish in tow. All was calm and right with the world around them. 

An Umibozu Approaches

That is, until that following evening, when a thick fog crept in without warning. There had been no signs of birds flying overhead. And the water had become eerily still over the last hour. 

Trying not to jump to conclusions, the captain suddenly remembered what the older woman had told him just a couple of weeks before. 

“Impossible,” he thought to himself. It’s just weird weather patterns; it’ll all blow over soon enough. “ 

But he couldn’t have been any more wrong. 

When the two youngest sailors had been taking watch, they noticed something dark and ominous slowly approaching their ship. As the whole crew gathered at the ship’s edge, trying to make out what was heading towards them, that’s when they saw it. 

At first, they thought it was two torches glowing through the fog from a nearby ship, but as the dark figure got closer, they realized these weren’t torches after all. No, these were two large, glowing eyes.

Standing there, with their hearts pounding in fear but standing nervously still, the water around them began to churn, and their ship violently began rocking back and forth. With its large, black torso that appeared to be made out of storm clouds and it’s serpentine limbs reaching out, that’s when the crew realized that this wasn’t a random storm, this was the Umibozu coming for them. 

The captain began frantically shouting commands to his men to take cover, but his voice was drowned out by the thunderous crashing of the waves surrounding them. Terrified of this creature, he called out, asking, “What do you want from us?” 

A Game of Riddles

With a throaty chuckle, the Umibozu’s booming voice said, “Your lives… or your vessel”. All the men on board feared for the worst. But, thinking quickly on his feet, the captain suddenly remembered one of the old beliefs about the Umibozu  – apparently, these oceanic yokai tricksters love a battle of wits. Think “The Hobbit, “where Bilbo Baggins and Gollum play the game of riddles. 

According to different variations of the Umibozu lore, it is said that they will demand either their lives directly or a barrel from the crew. With the barrel, it’s said that the Umibozu will fill the barrel with water onto the deck over and over to eventually sink the ship and drown those aboard. 

However, it’s also said that if a captain is smart enough, he can outthink his way out of the dark spirit’s clutches by offering an empty barrel with the bottom removed to preoccupy the Umibozu with just enough time for the sailors to make their lucky escape. And fortunately, that’s exactly what this captain had accomplished. He offered up an empty barrel just like the tales foretold, and Umibozu seemed pleased with this offer. 

With this, the captain and his crew decided to cut their fishing trip short and head back to the mainland, vowing never to dismiss another warning, no matter how bizarre a tale, again. 

Skeptic Beliefs, Speculations, and Supernatural Beliefs

So, what do we make of this creature? This, by far, isn’t the first aquatic cryptid we’ve covered on the show, nor will it be the last aquatic cryptid we speak of. Up until this particular story, many of these encounters have been well documented. Or, at least, more recently researched.

Remember the Flathead Lake Monster we covered just a few episodes ago? There were almost too many sightings to count. Or, if you go back to one of our very first episodes, the Iliamna Lake Monster, where the Alaska Army National Guard got involved in researching the unknown creature, there have been countless stories of water legends lurking about. But, many of these stories, skeptics believe, are just really big fish that had been misidentified or even a trick of the light casting an odd shadow. And, sure, many of these stories could be easily explained away with those theories.

But how do you explain the supernatural aura around the Umibozu? I mean, if a large, dark spirit is looming over your ship out at sea, trying to cause you to capsize, there’s no way a trick of the light or large sturgeon could shift the weather patterns and make for random torrential downpours. 

Well, some people believe that the Umibozu is a legitimate supernatural entity. One such theory is that the “Umibozu are the spirits of drowned priests, cast into the sea by angry villagers, where the priests were then transformed into ghosts due to the horrible nature of their death.”

Which side note: if you do a quick Google translation of the term Umi—meaning “sea” or ocean” in Japanese—and Bozu—meaning “monk,” the name literally translates to “Buddhist monk from the sea.”

Alternatively, others believe that the Umibozu actually consists of several different entities and is just a blanket team for“sea monsters” made up of a variety of aquatic yokai. Additionally, other legends include that the Umibozu are the spirits of the dead whose graves were not visited or cared for; thus, their spirits moved out of their graves and drifted into the sea. 

Another version of the Umibozu dates back to December 26th, 1888, when the Miyako Shinbun, Japan’s first daily newspaper, reported seeing an Umibozo that was described as, and I quote, “a monkey about 8ft tall, weighing up to 580 pounds, with brown hair and orange eyes.” Oh yeah, and it also had “the mouth of a crocodile, the torso of a fish, the tail of a lobster, and the cry of a bull.” 

I know this description may sound strange at first, but stick with me here. Due to the various animal body parts I just shared, some speculate that the Umibozu are actually shapeshifters and can turn into any type of creature they want. With this, there have also been theories that they can shapeshifter into “beautiful women,” also known as mermaids or sirens, that were known to lure men into the depths of the ocean, never to be seen again.

However, those who don’t believe in the supernatural suggest that this strange dark cloud is literally just that—a concoction of “cumulonimbus clouds and really big waves” and that the Umibozu is nothing more than mother nature simply drumming up a large storm. 

And then, of course, you have the belief that the creature really exists – but more so in a natural form. The descriptions still describe a large creature with a smooth, round head and serpentine-like arms, with up to five appendages that resemble a large hand. But to them, this is no water spirit – this is actually just an octopus.

One depiction suggests that the Umibozu is a hybrid of a dog, a human, and an octopus, with its hands ending in tentacles and fins on its spine. 

But then, with this theory, one could argue that it may not be an Umibozu after all but simply another colossal sea monster many sailors have also long known to fear—the Kraken. 

The Fear of the Kraken

For centuries, Norway, Greenland, and Iceland have all shared their own versions of the Kraken. Many sightings were popularized in the 1700s, but according to paleontologist Rodrigo Brincalepe Salvador, tales of the Kraken have been speculated to have first been spotted by King Sverre of Norway’s manuscript, dating back to 1180. 

Depictions of this sea monster include the body of your average squid or octopus, except maybe 10x its normal size – in fact, the Kraken is probably one of the largest, if not the largest, cryptids that have ever existed. As he writes, Rodrigo Salvador describes the Kraken as “perhaps the largest monster ever imagined by mankind.” 

And while you may have never heard of the Umibozu, it’s quite likely you’ve heard of the Kraken, as it’s often depicted in popular movies like Clash of the Titans, Leviathan, or Pirates of the Caribbean. Although these may be fictionalized works of art, I’d like to think the description of the Kraken from Pirates of the Caribbean may actually resemble what so many seafarers have known to fear. For in the quote where one of the characters from the movie describes the Kraken as “a fearsome creature with giant tentacles that’ll suction your face clean off, and drag an entire ship down to the crushing darkness… with the reeking odor of a thousand rotting corpses. If you believe such things.” 

While many of these stories often overly dramatize colossal squids for entertainment, that doesn’t mean these things don’t exist. Previously, much of what we knew about large squid, or any large oceanic creature for that matter, had been from studying them as they washed up on the beach or dragged from the depths by fishing gear. In fact, it wasn’t until 2012 that we were able to film these giant squid in their natural deep-sea habitats. But, even with documentation of large squid, their large size is still an anomaly to many, as some of these giant creatures can reach lengths up to 66 feet. 

Large Body of… Land?

Then again, even though large squid does, in fact, exist, that doesn’t mean every large thing sailors encountered out at sea had been the Kraken or even the Umibozu, for that matter. 

Without proof of these creatures, especially from century-old tales, we don’t really know what it is they claimed to have seen. Some even speculate that the large bodies many sailors saw were simply islands off in the distance. But, you may ask, how would they confuse dry land with aquatic beasts? Well, there are a variety of reasons they may have believed what they saw to be true. Some suggest it really was the trick of the light or the way fog set in on the water that it was hard to distinguish. 

Others claim it was due to their exhaustion from being on water for extended periods of time. Because of this exhaustion, seeing a mirage of something large could be a variety of things. And if you’ve seen Pirates of the Caribbean or know much about pirate lore, then you know rum was a common drink of choice. 

Of course, much of this rum acted as a preservative for their drinking water, preventing algae from contaminating their casks, which could have very much interfered with what they thought was real or not real if they happened to drink too much of it. 

And then there are others who suggest the sailors may have misidentified the Kraken with a whale. I don’t know about you, but the select few whales I’ve seen don’t have long, serpentine-like limbs that can wrap around large objects. But with many of these cryptid stories, I’m often left surprised by some of these findings. 

An Ocean of Possibilities

When it comes down to it, both the Umibozu and the Kraken are creatures born from the fear of the unknown. And when climbing aboard a ship, whether you’re a fisherman casting your nets to feed your community, a pirate looking for adventure out at sea, or simply vacationing on a cruise to travel new countries, the ocean is vast and mysterious and mother nature certainly has a mind of her own. 

And with these cryptid encounters and sailor’s warnings passed down from generation to generation, it’s hard not to wonder what’s really out there. But perhaps some of these things are meant to remain a mystery. As far as the Umibozu – a ghastly cryptid looking to capsize ships who also happens to have a penchant for riddles or the Kraken – a large squid that’s looking to devour entire ships whole for fun goes,  maybe these cryptids simply serve as a reminder that no matter how much we think we know, there are ways more beyond the horizon. 

And to end this story with yet another popular sailor’s adage, “Dead men tell no tales,” – may this remind us that sometimes the ocean’s darkest secrets are destined to remain just that, which may be the most thrilling part of all.

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