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10 Most Dangerous Marine Creatures popular


Submitted by xmesox on 2009-01-30 | Last Modified on 2010-03-19

Rating: 12345   Go Login to rate this article.   Votes: 4 | Comments: 6 | Views: 103900

1. Chironex (Box Jellyfish)

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This beautiful yet deadly animal is native to Northern Australia and is also some times referred to as the 'marine stinger' or 'sea wasp'. It is believed to be one of the, if not the most venomous creature around. This jellyfish has tentacles which are covered in high amounts of nematocysts as well as venom.

The Chironex is one of the largest jellyfish in these waters and it's bell can grow to the size of a soccer ball. Each corner of the bell has 15 tentacles.The sting from a Chironex can be fatal and is extremely painful, often associated with severe effects on the victims nervous system and heart. These jellyfish are known for their ability to kill a victim within 4 minutes, faster than any snake. If stung one should apply vinegar to the sting as to prevent nematocysts which have not yet been let off. CPR may also be required shortly after the sting has taken place. It is important if stung to immediately seek medical attention. An anti-venom for the Chironex does not exist, making the importance of experienced help a necessary.

So if you head to Northern Australia for some diving, be sure that you look out for warnings signs on beaches about these creatures and never take the threat of them lightly.


2. Crocodiles and Alligators

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When walking through certain marshes or lakes divers should always be aware to the fact that there may be a crocodile or alligator hidden just below the murky surface. These creatures are sometimes fed by humans which will only lead them to believe that humans are associated with their food source. This can start to become dangerous for people, leading to possible attacks.

A behavioural difference between crocodiles and alligators to Great White sharks is that while the Great White will almost always attack for feeding purposes, both the crocodile and alligator are highly territorial with the salt water crocodile being the most aggressive to humans. There's also been reports on crocodiles attacking small boats such as canoes. What most people don't realize is that despite it's appearance these animals can run extremely fast for their weight.

So while not posing a large threat on the average sea diver, the fresh water divers within the warm tropics should always be sure to keep an eye out for these creatures. It is often wise to speak to locals in the area about the marshes and lakes when diving in an unfamiliar area.


3. Blue-Ringed Octopus

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This small octopus rarely grows larger than 20 centimeters and is located in shadow waters and tidal pools in tropical areas. Depending on the mood of the octopus, the blue coloured rings upon it change in intensity and brightness.

The attack of this tiny creature can be deadly and there is no known antidote for a bite from it. The bite itself is not too painful, but the effects of the bite are catastrophic. The octopus has a neuromuscular paralysing venom which can cause paralysis and death within a short while. While there are occasions where if the victim is put on a respirator they can survive, getting bitten by one of these creatures is definitely one of the most dangerous things that can happen.

If you come close to one of these animals in the wild, you should be sure to keep your distance and do all in your power not to disturb it. You will be gambling with your life.


4. Stonefish

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This strange looking fish, despite it's somewhat small size (Growing up to 12 inches) is regarded as the most venomous fish in existence. It's camouflaged body can keep it perfectly hidden between rocks underwater, adding to its danger.

Stonefish are located primarily within the Indo-Pacific oceans, while there are some species which live in rivers. These fish are equipped with deadly dorsal fins which are like needles, they can secret some extremely poisonous neurotoxins. The results of a sting can be deadly if left untreated. Even if treated, the stings have an excruciating pain as well as large swelling for months, it can also cause the tissues around the stung area to die.

So if you're diving in an area with the Stonefish present, be on alert and be sure to examine each rock thoroughly before deciding to touch it. This fish definitely earns it's place on the list of 10 most dangerous marine creatures.


5. Great White

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This predator is no stranger to the list of dangerous animals and is almost constantly and incorrectly perceived as the world's most dangerous animal. The reality is that while the sharks attacks are gruesome and bloody, more people die annually from simple wasp and bee stings.

With that said the Great White is by no means a pushover and demands a lot of respect. This shark has an amazingly powerful jaw which is decorated with equally impressive design of razor sharp teeth. The Great White can grow to lengths in excess of 6 meters making it the largest predator on this list.

The nature of the Great White is often misunderstood, the Great White is not out on a mission to attack every human being that steps foot in the water. The Great White tends to attack humans when they are hunting for food, it's nothing more than basic instinct. This can be seen clearly when one looks at the amount of shark attacks on inanimate objects.


6. Tiger Shark

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The Tiger Shark can be found in plenty of areas and while the Great White seems to have the most feared reputation for attacks by a long shot, the Tiger Shark is right behind the Great White in fatal shark attacks. One of the reasons for this is the fact that the Tiger Shark is generally observed far closer to shore than Great Whites and are found in greater numbers.

While the Tiger Shark may not be as large as the Great White, it's by no means small with sizes in excess of 4 meters and a weight of up to a ton. Tiger Sharks are also known for their habit of eating old materials they find on the ocean floor. With pieces of tires sometimes being retrieved from their stomachs.

Definitely a creature to look out for when diving or swimming.


7. Stingrays

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Stingrays are one of the more passive creatures and hardly ever attack. The majority of stingray incidents happen when divers or swimmers accidentally step on them, causing the stingray to defend itself using it's sting. While majority of stingray 'attacks' are not serious, there are some stingray species which can be fatal.

So while attacks on people may be rare, there is potential for fatal attacks. One of the most popular marine attacks was actually from a stingray. The stingray attack on Steve Irwin on 4 September 2006, made international headlines and shocked the world. It is believed that the stingrays attack was due to the fact that there was a camera man ahead as well as Irwin behind the ray, this made the stingray feel threatened and it tried to defend itself. Sadly shortly after this incident, people thought it fit to attack stingrays in numbers in revenge for the defensive attack on Irwin.

When diving in an area with stingrays, try to keep your feet off the ocean floor and remain as non-threatening as possible to the creature. Attacks are rare and people shouldn't worry too much about swimming in an area with stingrays.


8. Sea Snakes

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These interesting marine creatures are located within the warm waters of the Indian Ocean and Pacific oceans. They resemble a cross between a land snake and that of an eel. The primary difference between a Sea Snake and an eel is the fact that a Sea Snake in fact does not have gills and needs to return to the surface for air.

Sea Snakes generally reach a maximum length of between 4 and 5 feet while some species can reach lengths of up to 10 feet.

Sea Snakes are not aggressive animals but due to the amount of toxicity in some of the species venom, they warrant a spot on the most dangerous marine creatures list. The Pelamis Platurus species is highly venomous and has the ability to be fatal to humans. So while attacks on humans may be rare, you don't want to go messing around with a Sea Snake.


9. Lionfish

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Like the Stonefish, the lionfish is also part of the 'Scorpionfish' family and is by far one of the most beautiful fish in the oceans. They have large, separated spines which give off a majestic aura. But don't let it's good looks fool you. While a sting from a lionfish is not deadly these fish can provide a very painful attack with some powerful venom.

They are found in the Caribbean and Eastern Atlantic. Divers are advised to take caution when observing these beautiful fish, and not to get too close or attempt to touch them.



10. Fire Coral

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This interesting life form is often confused with coral when it is really a type of marine organism which lives in large colonies. Fairly closely related to jellyfish and anemones these small organisms can deliver a power sting with it's invisible tentacles. The results can vary from a mild irritation to severe pains and is sometimes even associated with nausea and vomiting. So while the fire coral may not be deadly, it's fairly common and is often mistakenly handled by inexperienced scuba divers. Fire Coral is another reason for diving gloves

Before diving in an area with fire coral make sure you are aware as to what fire coral looks like and it's distinguishing traits. It is often mistaken for seaweed. The appearance of the fire coral is brown and a bright yellowy green. If you are in any way inclined to think that something which appears to be coral or seaweed may in fact be fire coral, rather be safe and stay clear of it with your skin.


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6 Comments CommentAdd a Comment

sangiro  sangiro
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 2009-02-04
5 out of 5 stars Nice article. Strange how all the dangerous marine creatures are also beautiful marine creatures... except maybe for that crocodile dude!
 jsalv10
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 2009-07-19
crocodile are cool and beautiful creatures so don't diss them they are one of the coolest creatures out there
 jsalv10
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 2009-07-19
the crocodile are cool and beautiful so don't diss the crocodiles
 mishapawan
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 2011-01-03
Very nice and informative article. I really appreciate the precise information about their sizes, kind of stings/bites and specially the warnings for divers.
 Jillybean
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 2011-03-23
I had dived with tiger sharks and they just went about their business. Sharks get a really bad reputation and I think it's unjust. I have plans to dive without a cage with great whites sometime soon :)
 mblac31
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 2012-02-27
i agree

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