The swamp has eyes…and teeth

There are about, 40 too many alligators in that water. But the thing about alligators is that they’re more afraid of you than you are of them, right?

Well, not really. These prehistoric reptiles don’t mess around. They can swim up to 20 mph and their jaws clamp down at 2,125 lbs. per square inch.

creepy, alligator eyes, spooky
Biosample via Reddit

Once they take hold of their prey, they typically drag it underwater and commence the “death roll,” which is just as terrifying as it sounds. Basically, it’s designed to tire out and drown their prey — as well as tear off a few bite-size chunks. Sometimes they’ll wait for their food to rot before consuming the rest. Lovely.

Parasitic eels in a frenzy

Around 880 meters below the surface, these parasitic eels feast on some bait. The way they group together and wriggle around makes them look a bit like one creature with many slimy arms. Without the light provided by the camera, this scene would be pitch black.

eels feeding, underwater, New Zealand
Museum of New Zealand Te Papa Tongarewa via Youtube

Parasitic eels have no jaws, but disk-shaped mouths with sharp teeth they use to latch onto their victims and suck their blood. If that doesn’t scare you, take a closeup look at their mouths. Just don’t expect to sleep well later.

What sharks see when circling beneath you

The grey reef sharks pictured below are amidst a feeding frenzy and I can’t think of a place I’d want to be less. Grey reef sharks are found primarily in the Indo-Pacific — anywhere between South Africa and Easter Island. They’re not known to attack humans unless provoked, so don’t provoke them.

sharks circling, looking up, scary
Reinhard Dirscherl\ullstein bild via Getty Images

Naturally curious, these predators are known to approach divers, but seldom bite humans. In fact, there have only been eight documented cases of grey reef shark attacks on people and only one of them was fatal. The grey shark displays a clear threat behavior when threatened or cornered, arching its back and swaying back and forth as a warning.

Octopuses leave no food on the table

By the look of it, this whale has been dead for quite awhile. This group of octopuses and other scavengers aren’t willing to let that good eating go to waste, though. Even though octopuses are primarily predators, the clever cephalopods are known to be opportunists as well.

whale carcass, skeleton, octopus eating
vdub319 via Reddit

The skeleton of a whale is creepy enough without all these creatures tearing the last remnants of flesh off the bones but in the ocean, nothing is wasted.

Something wicked this way comes

Imagine you’re out on a peaceful kayak trip and a giant fin pops up, speeding toward you from a distance. What do you do? Do turn and attempt to paddle away from the creature, or do you stay frozen in fear and hope it narrowly avoids you at the last minute?

orca, killer whale approach, oncoming
SeaLionBones via Reddit

Fortunately, this particular creature is a Killer Whale and, despite the name, these marine mammals have yet to kill a person. At least, not in the wild. That being said, there’s a first time for everything…

Open wide!

The basking shark is supposedly harmless to humans, but we wouldn’t want to take my chances near anything with a mouth that size. Fortunately, there have been no documented incidents of anyone being swallowed alive by a basking shark.

So if they don’t eat large prey, what’s the point of having such a big mouth?

Basking shark, scary creature, filter feeder
Chris Gotschalk via Wikimedia Commons

Basking sharks are filter feeders, meaning they feed on zooplankton by rushing forward and sucking in large quantities of water. The water is then filtered out through the gills as the prey is digested. This massive fish needs to take in a lot of water (and food) at once, so it needs a big mouth to get the job done. There is still much we don’t know about these gentle sea monsters.

Where thalassophobia meets claustrophobia

Part of what makes the ocean so terrifying is its profound vastness — but some areas are disturbing for the exact opposite reason. Take, for example, this scuba diver swimming through a tight cave. Imagine what you might come face to face with in the darkness and how impossible it would be to escape.

tight spot, cavediving, creepy
Imgur

It may be unlikely that you come upon an unidentified sea monster when cave-diving, but there are still many plausible ways you can meet your end if you’re not careful. Speaking of which…

He Who Dwells Beneath the Waves

This bronze statue of Jesus Christ was made by Guido Galletti and placed in the Mediterranean Sea off the coast of Italy. Titled “Christ of the Abyss,” the statue was first placed in 1954, but it was removed and restored in 2003 before being returned.

christ underwater, christ of the abyss, creepy
mjb_1911 via Reddit

The statue is a popular tourist attraction, and various other casts have been made and placed in other locations all over the world. It’s meant to depict Christ offering a benediction of peace, but many visitors find the statue more than a little bit haunting.

Cthulhu, is that you?

This is a picture of the first time a giant squid has ever been spotted in US waters. Researchers Dr. Nathan Robinson and Dr. Edie Widder dropped a deep-sea camera, called the Medusa, leagues beneath the sea in the Gulf of Mexico.

giant squid, deep water, rare creature
OceanX via Youtube

While reviewing the more than 20 hours of footage captured, the scientists began to worry that the mission had been uneventful. Then, all of a sudden, they noticed something very, very large come into the frame. Despite their humongous size, giant squid sightings are extremely rare, because the ocean is extremely deep, vast and terrifying.

Better hope he don’t want none

This gigantic anaconda has floated to the surface to take a peek at this submerged train. In case you forgot, these massive monsters are fully capable of swimming, sorry to remind you. But don’t worry, they don’t bite — at least not until after they’ve constricted and suffocated their prey.

anaconda, scary snake, underwater creature
via Imgur

The anaconda’s eyes are located on the top of its head, which allows it to keep its giant body hidden beneath the water until it’s time to strike. Fortunately, there are very few documented incidents of anacondas attacking and consuming humans.

Can ghosts swim?

There’s not much to find in Antarctica besides ice, death, and profound isolation. This boat sank while Brazilian journalist João Lara Mesquita and his crew struck the ice when filming a documentary. Luckily, the Chilean Navy was able to rescue the crew as the ship was sinking.

shipwreck, sunken ship, beneath
rose_thoro via Reddit

Waiting to be rescued must have seemed like days, as the boat slowly receded into its icy, watery grave. One year later, the crew returned to recover the ship. They were able to drag it from the depths but, by then, the water and cold had taken their toll, leaving it was beyond repair.

The first underwater photograph?

There’s some debate as to whether or not this is really the first underwater photo ever taken — but it’s well accepted that it’s likely the first portrait ever taken underwater. There are lots of fascinating rumors surrounding the picture, though it’s hard to sort out what’s true.

portrait, deepwater, underwater
Louis Boutan via Imgur

We do know that the man in the photo is oceanographer Emil Racovitza and that the photo was taken by Louis Boutan in South France, probably in 1899.

Rumor has it, Boutan and Rocovitza captured the photo at an astounding 164-foot depth and the exposure had to be set to 30 minutes to let in enough light to capture the image. Boutan allegedly suffered from Nitrogen narcosis as a result.

The deeper you go, the darker it gets

Unlike many of the other photos on this list, there aren’t any monsters, swimming or slithering about. At least not that we can see. Still, emptiness is terrifying in its own right — and cave diving is extremely dangerous for other reasons, especially when freediving like the gentleman pictured below.

cave diving, freediving, underwater
josiahwg via Bunnyport

In the dark, it’s easy to get lost in the caverns. If you run out of air and need to resurface for a breath and look up to find only solid rock above you, the cave will likely become your tomb. Personally, we’d rather leave the exploring to the professional photographers and their subjects.

Hope that ice is thick

No one knows how deep this hole is — estimates range from 300 to 1,000 feet — or what’s at the bottom of it. All that covers the void is a sheet of ice. Stand on it if you dare.

deep hole, long way down, ice sheet
Import via Reddit

In truth, it’s probably not as dangerous as it looks. The hole is full of water, so you’re not likely to plunge to your death down the bottomless pit. However, it would be incredibly cold — and who knows what’s down there.

Close to shore

I should be safe if I don’t swim out to far, right? Hmm, maybe not. It’s unclear why this shark is swimming so close to the shore, but it’s unlikely it’s to go sunbathing. Shark attacks on humans are uncommon but, when it happens, tiger sharks are often to blame.

shark close up, dangerous, close to shore
tornAtoe via Reddit

Unfortunately for us humans, tiger sharks are often found in the places we like to visit: They prefer warm water, so they’re often found in places like the Bahamas, Brazil, and Hawaii.

Davy Jones’ locker

Deep Discoverer, the National Oceanic and Atmospheric Administration’s remote-operated vehicle used to explore and collect samples from depths up to 3.7 miles below the surface, came upon this unknown ship at the bottom of the Gulf of Mexico during a routine exploration.

deep water wreck, depths, old ship
NOAA Ocean Exploration & Research via Flickr

The Deep Discoverer, or D2, took lots of photos, which were used to generate a 3D mosaic survey of the shipwreck. Based on the organisms observed and the style of ship, researchers believe it was a merchant vessel that has been there since around 1830. Do we even want to know what brought it down?

Surfer had no clue

One day, surfer and musician Brad Coder paddled out in El Porto Beach, Calif. with his GoPro to capture some footage for a new music video. When he sifted through the footage later, he noticed this — proof he wasn’t as alone, as he thought he was.

shark circling, underwater, close call
gabriellorden via Imgur

If that was us, we’d be fine not noticing it at the time — and be happy that the shark wasn’t hungry enough to try a bite. Judging by its size, it’s most likely a juvenile great white. Luckily, these sharks prefer to feast on fish and stingrays. When they get older and bigger, they’ll start going after seals, and you don’t want to be around that.

That’s one big blob

This Nomura’s jellyfish doesn’t just look scary, it really is dangerous. These invasive species have been wreaking havoc on Japanese fisheries for the last 20 years. The sting from their tentacles is extremely painful and, in rare cases, potentially fatal. Of course, the fact that they’re larger than the average man doesn’t help matters either.

giant jellyfish, Nomura's jellyfish, big jellyfish
YourFellaThere via Reddit

The cause of the recent population boom of these terrifying cnidarians is unclear, but it’s dire enough to cause researchers to scramble for solutions, like grinding them up to turn into fertilizer or using them to make ice cream. One thing’s for sure, you’re more likely than ever to run into one of these things if you go diving in China or Japan.

The Mariana Trench is dark and full of terrors

This is a dumbo octopus. While it’s considerably less cute than its namesake, you can see how its earlike fins lent this cephalopod its name. According to National Oceanic and Atmospheric Administration Ocean Exploration & Research, this is the first time this creature has been observed coiling its arms this way.

Side note: Octopuses don’t have tentacles, they have arms.

dumbo octopus, mariana trench, scary creatures
NOAA Ocean Exploration & Research via Flickr

If you’re scared of this guy, don’t worry. You won’t run into one less than 13,100 feet below the surface. The Mariana Trench is about 7 miles deep, and it’s only been within the last seven years since man has been able to reach the bottom. James Cameron (yes, the filmmaker) is the only person to date to make the journey.

The edge of the earth?

This may not be what it looks like, but it’s still pretty freaky. This is actually an optical illusion caused by currents moving the sediment at the bottom of the ocean. While this may not be water falling off the edge of the world, the truth behind the illusion is terrifying in its own right.

underwater waterfall, island, deep
Flying-Pup via Reddit

The effect is caused by a sudden drop off the coast of the island of Mauritius in the Indian Ocean — it’s the edge of the shelf where the ocean floor suddenly drops from 150 meters below sea level to 4,000 meters. Aerial photographs like this one show us what it looks like when currents carry sand off the edge into the deep abyss.

Underwater plane wreck

This Japanese warplane went down during the Operation Hailstone attack — it was one of 250 planes that were destroyed by Allied forces, dealing a crucial blow to the Imperial Japanese Navy and clearing the path for an Allied invasion of Japan.

plane wreck WWI, underwater, scary
Yanu ari via Youtube

Three quarters of a century later, many of the destroyed warplanes remain at the bottom of Truk Lagoon. Above, a diver gets a closeup of one such plane, covered in coral — a sight that is both beautiful and unsettling.

Big wave

Sometimes. there doesn’t need to be a creepy creature or shipwreck to make the ocean terrifying. Sometimes, just water is enough — in this case, lots of water moving incredibly fast. Nazaré, Portugal is unique in that its coast is so exposed and, unlike other big wave spots, the ocean bottom there is sand, not rock.

big wave, nazare, portugal
Luis Ascenso via Flickr

This means there’s virtually nothing to stop or slow the massive swells as they approach the coastline. Surfers from all around the world flock to Nazaré to ride the massive waves, and numerous world records have been set there.

Portuguese Man of War

This blob can kill you or, at the very least, ruin your day. The Portuguese Man of War has tentacles that can stretch up to 165 feet. These tentacles are covered in nematocysts that deliver a barbed thread filled with venom that gets under the skin, causing partial paralysis, difficulty breathing, low blood pressure, and excruciating pain.

Portuguese Man of War, jellyfish, dangerous
Jon Seekford via Flickr

It’s rare the Portuguese Man of War will take a human’s life, but it’s not unheard of. When you consider a long distance swimmer far from shore coming in contact with a string of tentacles, it’s easy to grasp why they pose a major threat. Oh yeah, they can sting you even when they’re dead, too. 

Help wanted: Must know your way around a broom

These reptiles are deadly efficient at what they do. Crocodylomorphs evolved on land around 200 million years ago and, since then, they have only become more adept at killing. Sadly, they have never evolved the ability to scratch their own backs.

back scratch, crocodile, reptile, scary
monalistic via Imgur

We’re looking for a hardworking, self-motivated person to fill the position of crocodile backscratcher. Must be hygienic, a great communicator and, above all, fearless. We’d like to fill this position immediately because our last guy, uh… quit unexpectedly. Apply online.

Welcome sign

We’re not sure we’d need this sign to keep us out, but perhaps there are braver souls out there that need to be reminded of their mortality. This lovely sign is located near the entrance of a cave in Vortex Spring, a popular recreational diving area for experts and novices alike.

sign, scary sign, cavedive, creepy
Greg Grimes via Wikimedia Commons

After 13 inexperienced divers perished in the cave in the 1990s, a certification program was instituted to make divers undergo specific training to be allowed access to caves like this one. In 2010, an uncertified diver snuck into the cave never to return. His body was never recovered.

Nightmare fish

According to Deep Sea News, this is some kind of goby, probably from the genus Taenioides. Whatever it is, it’s pretty ugly, and more than a little terrifying too. This thing is likely from muddy, brackish waters, since its small eyes suggest it doesn’t need to see too well — in case you needed another reason to be scared of what you can’t see in the dark.

terrifying fish, goby, scary fish
Distort303 via Youtube

Perhaps this creature is just misunderstood and doesn’t mean us any harm. All we know is that it’s hard to look at this fish for more than a few seconds without our flesh crawling. Anyway, that’s enough of this thing, let’s move on…

Capsized cruise ship

Cruise ships are supposed to be fun. When you’re four cocktails deep and on your third trip to the buffet, the worst fear that crosses your mind is whether or not seasickness will finally hit you during shuffleboard. It’s easy to forget you’re out at sea, miles away from land and safety.

capsized ship, cruise ship, ship went down
Tullio M. Puglia via Getty Images

This particular ship didn’t even have to sail out that far for disaster to strike. Unfortunately, the Costa Concordia struck a submerged rock, which caused it to take on water and sink slowly. Failure to hastily evacuate the ship led to dozens of casualties and the captain was brought up on criminal charges.

What lies beneath?

We don’t want to know, but clearly this baby is unbothered by the pitch-black abyss less than a foot beneath his tiny feet.

Do you think ignorance is bliss, or is this infant just a lot more courageous than us?

baby above the black, scary water
kevinttan via Reddit

Even still water can feel incredibly ominous. It’s hard not to imagine what could be lurking beneath in the pitch-black darkness. Sharks? Alligators? Snakes? Giant squid? Cthulhu? Perhaps we’re better off not knowing…

Nope

This may look like a grotesque version of a pill bug, but it’s actually a giant isopod, or Bathynomus giganteus if you prefer. This handsome guy was caught in a fish trap set by Bob Carney. Giant isopods are typically found in cold climates, where it’s nice and deep. They’re considered another example of “deep-sea gigantism,” which essentially means the deeper the environment, the bigger the creature. 

giant isopod, water bug, creepy, ugly
NOAA Ocean Exploration & Research via Flickr

They don’t really pose any threat to humans, but they still give us the creeps. Apparently, they taste a bit like shrimp or crab. If you’re not sufficiently creeped out, check out this video of them consuming an alligator carcass, for science!

Absolute unit

These people must have gotten more than they bargained for while sailing in Papua West, when this gigantic whale shark popped up next to the boat to say hello. The giant mouthed creatures are a rare sight — they’re currently endangered — but like the open water in warmer parts of the ocean.

whale shark, filter feeder, large shark, big fish
onomonopizza via Reddit

While their enormous size is more than enough to inspire terror, the whale shark actually poses almost no threat to humans. Their big mouths are designed to feed on plankton, not the flesh and bone of innocent swimmers. They usually pay humans little to no mind when they come in contact with them.