Idiots Guide: 12 Deadliest Creatures in the Sea

Steven Speilberg’s 1975 film ‘Jaws’ set the standard for fear when it comes to ocean creatures, the great white shark in particular. In reality sharks are but a small minority of deadly creatures that inhabit our oceans and seas throughout the world. Many of these animals kill many of us, each year. They say that there’s a million ways to die, I dare say that they failed to include some of these strange, diabolically effective and deadly sea animals. Idiots Guide presents a look at ’12 of the Most Deadly Creatures in our Oceans’.




#12.   Stonefish


You can find a ‘Stonefish’ (Synanceia) in the warm coastal waters of the Indo-Pacific Ocean. The problem is that they are extremely dangerous and easy to mistake for a pretty reef corral shell. They are among the most venomous fish in the world and their venom can kill you, dead. Stonefish aren’t aggressive by nature, most of their victims are divers who accidentally step on them which triggers a nasty sting by it’s needle sharp dorsal fin spines loaded with neurotoxins, which again, can kill you. So Idiots Guide advises being careful where you put your feet the next time you go scuba diving in the Indio-Pacific.

#11.   Leopard Seal

Leopard Seal 2

Here’s the news… Leopard Seals have been known to hunt people down. Several explorers have been attacked where the Leopard Seal inflicted serious bites before trying to drag their bodies into the sea. This is an animal that is one of Antarctica’s top predators and they aren’t afraid of humans. They can weigh as much as 1,200 pounds and carry a serious set of canine teeth used to shred flesh, usually penguin flesh, but they aren’t adverse to using them on us, so keep your distance. The next time you’re in the Antarctic…

#10.   Lionfish

Lionfish 2

Lionfish aka (Pterois) have the look of a fish that you shouldn’t mess with and guess what? You shouldn’t mess with them. They are packing venomous spiky fin rays and the venom causes extreme pain, nausea, vomiting, fever, convulsions, dizziness, heartburn and even diarrhea. Gross, I know.  In some instances a Lionfish sting can cause paralysis, heart failure followed by death. Especially at risk of death are young children, the elderly and people with a weakened immune systems. This is a formidable invasive species that people need to stay clear of, basically at all times. Divers and fisherman throughout the Indio-Pacific and tropics have their hands full with these ugly venomous suckers.

#9.   Moray Eel

Moray Eel

Not only do Moray Eels have razor sharp teeth, they also have a second set of teeth that sit on it’s second jaw. That’s right, this animal has two jaws or a ‘pharyngeal jaw’ for the scientists among us.  Moray Eels don’t prefer to attack humans, in fact they usually do so only in either self defense or an accidental disruption of their living space. When that happens all bets are off, they react aggressively and don’t retreat.  When divers try and feed these creatures (ill-advised) they occasionally lose a finger or three as Eels have terrible eyesight and easily mistake fingers for food. An even bigger problem is that once they latch onto a human hand, they don’t let it go, even if they die, not without a pair of serious pliers to pry them off and try and save what’s left of the hand. Advise? Like all the other usual suspects on this list…stay clear if you know what’s good for you.

#8.  Flower Urchin

Flower Urchin

“Look honey, it’s a pretty flower like corral!” Actually it’s a Flower Sea Urchin and it’s mad dangerous. If you touch it you can expect to receive an extremely painful sting that usually requires immediate medical attention. It’s venom has up to three different toxins in it and none of them are good news. The kind of toxins that can result in anesthetic coma, convulsions and even death. Still want to mess with that flower? I wouldn’t. For those of you who want to admire this creature in person (hopefully, from a distance) you can find them hanging around the  Indo-West Pacific Ocean.

#7.   Barracuda


Barracuda’s look like bad-asses and they are exactly that, ferocious predators with seriously sharp, fang shaped teeth on the business end. They are not above scavenging and often will mistake a human swimmer and/or diver for prey, at that point an attack happens and it isn’t pretty. They have been known to break ribs, tear flesh away from bone and sometimes kill people. They don’t hunt human but their poor eyesight causes problems of mistaken identity. The bottom line is if you find yourself in and around the Atlantic Ocean, Red Sea and/or Caribbean Sea, be aware of the ‘Cuda and stay way clear.

#6.  Banded Sea Snake

Sea Snakes

Sometimes it seems that a person just can’t avoid snakes. You would think that the ocean would be a safe place, but alas it’s not. The Banded Sea Snake is a species of venomous snake typically found in warm, tropical Indo-Pacific Oceanic waters. Luckily, they are easy to spot as they have a distinctive black stripe pattern on their bodies. Much like their terrestrial cousins, these snakes possess serious venom that contains neurotoxins and myotoxins. The neurotoxins attack nerve cells, paralyze the respiratory system, followed by death. The myotoxins attack skeletal muscles and breathing. Double trouble. Just as avoiding snakes on land is advisable, so to is the advise with the sea snake variety.

#5.  Textile Cone Snail

Textile Cone Snail

The ‘Textile Cone Snail’ aka (Conus textile) is an extremely venomous species of sea snail. They are adept predators and have been known to sting unsuspecting humans. A sting which possesses a ‘Conotoxin’ which they inject into their victims via a ‘Radula Tooth’ which is best described as a mini harpoon which they can fire a variety of toxins in any direction, even backwards. Sweet, right? Unfortunately, people make the mistake of picking these animals up and exposing themselves to a battery of stings that can even penetrate wetsuits, when that happens victims can expect total limb numbness throughout the entire body, paralysis, paralysis of the diaphragm which prevents breathing. In severe cases, coma and death will occur. Bottom line is, that pretty shell you see might very well be the death of you if you try and pick it up.

#4.   Blue Ringed Octopus

Blue Ringed Octopus

The Blue Ringed Octopus is widely considered to be one of the world’s most venomous marine creatures. Their outwardly timid nature belies their toxic venom that contains ‘Tetrodotoxin’, which is a powerful neurotoxin that can easily kill any human being. In fact it’s potent enough to kill 26 adult human beings in the course of just several minutes. This species is easy to spot due to their characteristic blue and black ringed bodies. Victims can expect respiratory depression and paralysis, followed by immediate death. Bad news.

#3.    Salt Water Crocodile

Saltwater Crocodile 2

Confession time, I happen to despise Salt Water Crocodiles. In fact I despise basically the entire alligator, crocodile, cayman family. This isn’t just because I fear them, and I do fear them, it’s because they are flat out ugly. Sinister doesn’t quite capture their essence, the fact that they are well known man-eaters doesn’t help their cause either. This apex, ambush predator will eat just about anything it can fit in it’s mouth, and that’s a huge mouth. They don’t chew, they swallow whole. They kill hundreds of human beings around the world every year. They will kill and eat you if you give them 1/2 a chance. Experts claim that they are wary of humans, but I don’t buy it, they eat too many of us for that claim to ring true to this author. These beasts grow to 20 feet long and can easily weigh over a ton (2,000 pounds). You can find them almost anywhere there’s water, which sucks, places like mangrove swamps, estuaries, deltas, lagoons, and rivers. Nightmare animal, period.

#2.   Great White Shark


Great White Shark’s fare no better on my list of despised creatures, in fact all aggressive man-eating sharks are on my permanent sh*t list (i.e.. Tiger Shark, Bull Shark). They are hands down the apex predators of the sea and have zero problem killing and eating any mammalian that happens to be around them in the water. They don’t like how we taste but they’ll still kill the sh*t out of you. Ask any seal how they feel about these guys. They are responsible for the most fatal and unprovoked attacks on humans in the ocean. It’s true that they, just like the crocodile, are an evolutionary marvel of killing machine animal. It doesn’t change the fact that I hate them. I refuse to go where they live.

#1.    Box Jellyfish

Box Jellyfish

Box Jellyfish hold the #1 rank of nightmare sea creature. In fact it’s widely considered to be ‘The world’s most venomous creature’. It’s stings produce an extremely potent venom that if it doesn’t kill a person, will make that person wish that he/she were dead for sure. Their stings kill hundreds of innocent children every year, and many adults as well. A sting from the ‘Irukandji Jellyfish’ is considered to be the world’s most painful by far and also contributes immensely severe physical and psychological symptoms, known to the world  as ‘Irukandji Syndrome’. An absolute nightmare of a sea creature. The worst part (if possible) is that they are basically transparent, so you don’t see them coming. Sweet, right? It’s been said that it’s best to avoid them after full moons and calm water, but the fact of the matter is they can strike anywhere at virtually anytime. Good luck out there.