19 Most Dangerous Sea Creatures

Edited by Kathy McGraw, Maria Quinney

The oceans and seas of the world are deep, dark, and mysterious, and the creatures that live there are no less so. From the deadly beauty of a great white shark cruising the currents near the surface to the seemingly benign flowers protruding from the flower urchin, danger lurks in many forms. The following 19 sea creatures are some of the most dangerous in the world.

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    Great White Shark. The deadly Great White Shark is one of the apex predators of the deep. Growing to over 20 feet in length, this shark has rows of serrated teeth and a powerful bite that can mean bad news for any swimmer that it mistakes for its normal prey of sea lions, seals, and small cetaceans. It is found in all of the oceans of the world, mostly in coastal waters, and it is considered to be a vulnerable species due to being trapped in fishing nets and overzealous sports fishing.
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    Tiger Shark. With its cosmopolitan diet that ranges from fish to sea mammals, the Tiger Shark is a wide-ranging fish that frequents reefs and other coastal areas where people are likely to swim. While it does not seek out humans as prey, it is opportunistic enough to take a bite out of you if it thinks you resemble something tasty.
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    Box Jellyfish. Floating in the waters of the Pacific and Indian Oceans are this alien-appearing, yet seemingly harmless looking creatures. However, don't be fooled: they are extremely poisonous to humans. The National Science Foundation states that as many as 20 to 40 people die every year in the Philippines from stings by box jellyfish.
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    Faint-Banded Sea Snake. Also known of Belcher's sea snake, this colorful sea serpent is native to the Indian and Pacific oceans. While it generally won't bother you if you don't bother it, its venom is so poisonous that just one drop can kill up to 1,800 people. It's best to just leave this beautiful sea snake alone.
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    Stonefish. Aptly named, the Stonefish lies on the bottom of the sea floor. Its markings make it look like a harmless rock, but if you step on it, you're in for a world of hurt. It is one of the most venomous fish in the sea, capable of putting you in the hospital or even killing you if you don't get treated quickly enough.
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    Flower Urchin. This beautiful sea urchin has a unique defense mechanism: it is covered with what appear to be flowers, but they are actually little pincers that deliver a virulent poison capable of killing a human.
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    Titan Triggerfish. Titan triggerfish are large fish that live in the Indian and Pacific oceans. They have powerful jaws and sharp teeth and will defend their territory against foreign incursions, which means SCUBA divers should beware if any of these dangerous creatures are nearby.
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    Olive Sea Snake. Found in the waters of the Indian and Pacific oceans, the Olive Sea Snake is quite poisonous, with a venom that is stronger than that of a cobra. However, if you leave it alone, it is unlikely to bother you.
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    Barracuda. Growing up to 7 feet in length, barracuda have vicious teeth, powerful jaws, and a whip-like body that can deliver a powerful punch to anyone unlucky enough to get on the wrong side of one of these fish. While attacks on humans are not common, and most barracuda would rather swim away from trouble than confront it, attacks can and do happen from time to time.
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    Textile Cone Snail. This sea snail is native to the coral reef areas of Australia. It is poisonous and secretes a unique venom that is powerful enough to fell, 20 humans. The type of venom is called a conotoxin, which affects specific nerves in the body. It can kill you within minutes, and it won't feel too good while it's doing it, either.
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    Saltwater Crocodile. This large reptile lives in brackish rivers close to where the river water meets the oceans. They are highly opportunistic feeders who may decide that you look like lunch, and with a bite force that is 10 times as strong as the bite of a great white shark, that's very bad news for you.
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    Blue Ring Octopus. This colorful cephalopod is one of the most venomous creatures on the planet. Its venom is capable of killing 26 grown men very quickly. Since there is no antidote for blue octopus venom, it's best not to get near this little guy.
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    Stingray. Stingrays are normally shy creatures that would just as soon as avoid you as interact with you. That said, they bury themselves in the sea bottom in shallow water areas, which puts people at risk for stepping on one and getting stung or injured by its long barbed tail. It was a stingray's tail that caused the death of noted crocodile hunter, Steve Irwin in 2006. A stingray's tail pierced his heart and killed him.
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    Lionfish. Popular fish for home aquarium aficionados, the Lionfish has a venom that, while not fatal to humans, will make you wish you were dead for an hour or two after you are stung. According to the National Oceanic and Atmospheric Administration (NOAA), a sting from a lionfish can cause a headache, nausea, vomiting, and a tingling sensation in the extremities.
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    Indonesian Needlefish. In the waters of Indonesia swims this peculiar fish. It has a long needle-like snout and a body that is shaped like a dagger. The reason it is dangerous is that it leaps out of the water at speeds up to 37 mph, and if you are in the way, you can get quite literally speared by these little torpedoes.
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    Portuguese Man of War. Spending its life floating in the ocean wherever the currents take it, the Portuguese Man of War is not a jelly fish, although it is similar to one. It has no means of propulsion, so it is entirely at the mercy of the sea currents. You don't want to get near one because it is poisonous to the touch, and while it probably isn't capable of killing a human with its venom, it can cause you a lot of pain if it stings you.
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    Dolphin. Dolphins are cute and cuddly, right? Well, that's one side of them; the other side to these intelligent mammals is that they can be jerks. Dolphins have been known to kill for fun, and there have been cases where people have been sexually assaulted by over-eager dolphins in the wild.
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    Killer Whale (Orca). Of the two types of killer whales that populate the world's oceans, the one that is most likely to pose a danger to humans are the transients who feed on other sea mammals such as baleen whales and seals. These whales can be aggressive when they are hungry or feel threatened. While there have been no cases of a wild killer whale attacking a human being, it is wise to be cautious around them all the same.
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    Sperm Whale. Sperm whales are large toothed whales that are found in all of the world's oceans. Males reach a length of around 60 feet, while females get up to about 40 feet. They eat fish, octopus, and giant squid. Sperm whales can be dangerous to humans if they perceive them to be a threat, and you don't want a creature the size of a bus to come after you.
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Categories : Animals & Pets

Recent edits by: Kathy McGraw

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