10 Deadly Ocean Creatures

The ocean is our favorite hangout, colorfully decorated and home to some of the most fascinating characters, some of which are potentially dangerous. To stay safe, you need to watch your step, keep your hands to yourself, respect the residents, and steer clear of some of the more dangerous denizens. In this article, we introduce you to nine sea creatures (in no particular order) to appreciate from a distance and the deadliest creature on land or sea.

Our goal is to inspire awe and respect, not fear. Every creature mentioned has adapted to survive and thrive in the ocean ecosystem. Some are large and fast with powerful jaws and big teeth, others use camouflage to their advantage, some are really smart, some carry toxins, and others pack a weapon, but we love them all and hope you do, too.

Note: We want to give a special shout out to our dear friend and a person with a super cool job, Prof Jamie Seymour, PhD, at James Cook University. As a leading toxicologist/venomologist, he works with many of these deadly animals every day. Talk about brave.

Saltwater Crocodiles

Saltwater crocs can grow in excess of 20 feet and 2,000 pounds They have big teeth, powerful jaws, can run about 15 miles per hour (in short sprints) and swim about 20 miles an hour. You may be able to outrun one, but you can’t outswim one.

Three characteristics make them particularly deadly. First, they’re aggressive. You don’t need to poke ‘em with a stick to make ‘em mad. All you need to do is invade their personal space. Second, they ambush their prey. They hang out very still at the water’s edge, sometimes half buried, until an unsuspecting monkey, boar, water buffalo, or other animal drops by for a drink—then bam! They clamp down and won’t let go. Third, immediately after clamping down, they do a death roll to drown and dismember the body, so if the initial attack doesn’t kill you, you’ll soon wish it would have.

Saltwater crocs have even been known to attack and eat sharks. We’re guessing the winner would come down to size and to who surprised whom.

Fugu Fish

Fugu fish, a type of pufferfish or blowfish, are considered by some to be a delicacy. However, if not prepared properly, this fish could be the last one you ever eat. When threatened, the pufferfish can blow itself up to several times its normal size, and some are covered with spines. If the predator doesn’t take the hint and ends up eating the pufferfish, it’s in for a rude surprise—the pufferfish contains a toxin that makes them taste horrible and is potentially deadly. In fact, this cute little puff of joy carries enough toxin to kill up to 30 adult humans, and it has no known antidote.

Eating fugu is like playing Russian Roulette with your dinner. Tetrodotoxin, stored in the liver, ovaries, and other parts of this fish, may be more toxic than cyanide. A small dose of tetrodotoxin could result in numbness in your mouth, vomiting, paralysis and possibly death. We recommend crossing it off your menu.

The pufferfish is poisonous, not venomous. What’s the difference? A poisonous animal is toxic but doesn’t actively deliver the toxin — you have to touch it or eat it. In contrast, venom is delivered intentionally; for example, through a bite or sting. Some animals, such as a spitting cobra, are toxungen, meaning they spit, spray, or fling their toxins.

Killer Whales

Their name says it all. Killer whales (orcas) are one of the few mammals that kill for fun. In fact, they hunt in packs and teach their calves how to hunt from an early age. They’re also big, powerful, and smart, making them one of the most formidable ocean predators. In a meet up between a killer whale and a great white shark, the killer whale would likely prevail. They’ve even developed a special technique for dealing with sharks—biting the shark and turning it on its back to put the shark in a coma-like state called tonic immobility. Told you they were smart.

While orcas in captivity have fatally wounded people (another reason to #EmptyTheTanks), none has ever been reported to have killed a human in the wild.

Blue-Ringed Octopus

Beautiful and deadly, the blue-ringed octopus is named after the vibrant blue circles it shows when feeling threatened. Though docile, their bite contains the powerful neurotoxin called tetrodotoxin (the same toxin carried by the fugu pufferfish). The octopus uses the venom to immobilize its prey for an easier meal that doesn’t wiggle around. Fortunately for the octopus eating this tainted meal, it’s immune to its own venom, but you most certainly are not!

Sea Snake

While snake enthusiasts can’t agree on the most venomous snake, they do agree that sea snakes are super venomous But, venomous and deadly are two different things. Sea snakes are very docile, and they don’t have huge front fangs like those of cobras, so they’re not likely to bite you. Even if they do, they may not deliver enough venom to kill you. However, if you were to get a good dose of it, good luck. It’s highly concentrated.

Stone Fish

The stone fish holds the title for most venomous fish in the world, but you may not even notice them, because they look like rocks. Well, you may not notice until you step on one. Then, holy fugu fish, do they ever pack a lethal punch! The first sign of trouble is that your foot becomes impaled on the spikes of their dorsal fins (exceedingly painful). Then, the toxin enters the bloodstream causing swelling around the wound, difficulty breathing, irregular or no heartbeat, nausea, vomiting, delirium, and even death.

The good news is that as long as you don’t step on one, or accidently grab it, you have little to fear.

Sharks (But Not All of Them)

Many sharks are apex predators that play a key role in maintaining a healthy ocean. These predators are big, strong, and fast and are equipped with big, sharp teeth and strong jaws. But some sharks pose a greater threat than others. Some of the deadliest (to humans) sharks include the following:

• Great white shark
• Tiger shark
• Bull shark
• Oceanic whitetip shark
• Blue shark
• Shortfin mako shark

However, the vast majority of sharks are relatively harmless to humans, including the following:

• Whale shark
• Nurse shark (as long as it’s not harassed)
• Basking shark
• Leopard shark
• Angel shark
• Bamboo shark

Even predatory sharks pose a nearly negligible risk to humans.

Cone Snails

Yep, this beautiful little snail is a vicious predator. Experts hypothesize that a single cone snail contains enough venom to kill 700 adult humans. Like other snails, the cone snail is slow, so it uses a harpoon-like tooth to inject venom into its prey, quickly immobilizing the prey so the snail can eat it. If you’re on the receiving end of one of the snail’s venom-tipped harpoons, head to the hospital; death can occur within one to five hours in severe cases.

While there is no anti-venom, on the bright side, scientists have used the venom to create better, non-addictive painkillers and insulin.

Box Jellyfish

While people tend to fear sharks the most, if they’re going to be afraid of anything in the ocean, it should be the box jellyfish. They’re translucent, so you can barely see them in the water. They’re much better swimmers than most jellies. They have lots of eyes (24 to be precise). They deliver their venom on contact, and a sting from the most venomous of the group can result in paralysis, cardiac arrest, or even death in a matter of two to five minutes. Yikes.

Humans

Even with all these deadly creatures in the sea, from tiny cone snails to giant predators much larger than people, humans are the most dangerous creature out there. Over the past 40 years, thanks to humans, 50 percent of the biodiversity on earth has disappeared and over 1,000 species go extinct each year. Every year, humans are responsible for killing hundreds of millions of sharks; billions of pounds of fishing bycatch; and more than 300,000 small whales, dolphins, and porpoises (due to fishing line entanglement), not to mention the fact that every year humans murder about 450,000 other humans. Man, we really are the deadliest species on the planet.