Every year, accidents involving tourists on vacation occur around the world. Improper behavior on the water, abuse of alcoholic beverages, and ignorance of basic safety standards lead to disastrous consequences.
Exotic holidays are also popular among Russian tourists, where you can get acquainted with the diverse fauna of the warm seas. For example, in Egypt, an excursion offered scuba diving in the open sea, where vacationers could take pictures of beautiful fish and touch them with their hands. However, no one warned that almost half of them are poisonous and pose a danger to humans, including death.
Due to the deterioration of the environmental situation throughout the world, large predators in search of prey migrate to places unusual for their habitat and swim close to the shore. For example, in 2011, a record number of shark attacks on people were recorded around the world. In Primorye, where sharks had never previously swum to the shore or shown aggression, several such cases have occurred. Also in 2015, sharks attacked tourists in the most popular resorts in Egypt. Therefore, before going on a sea holiday, it is important to know simple safety rules when swimming in the sea.
Basic safety rules at sea
- Before going on a sea holiday, study the inhabitants that pose a danger to humans.
- While in the water, do not touch sea creatures with your hands.
- Do not swim in the sea at night or at dawn, or alone.
- Avoid swimming in conditions of poor visibility and turbid water.
- Look carefully at your step when entering the sea.
- Wear special shoes near coral reefs.
- It is not recommended to swim during strong winds or after a storm, as many jellyfish wash ashore.
- Choose soft-colored swimsuits and swim trunks to avoid attracting the attention of sharks and other dangerous fish.
- Do not swim further than 10 meters from the shore.
- Pay attention to the signs and flags on the beach. The color of the flag can signal danger.
Let us examine in more detail the main marine inhabitants that pose a danger to humans.
Jellyfish
Jellyfish have special stinging cells with poison on their bodies that can cause severe burns. As a rule, they are in a fringe that hangs under the dome. Many jellyfish that live in Russian seas are absolutely harmless, and touching them will practically not cause a burn.
Very often you can see children playing with jellyfish and throwing them at each other. However, among a large number of harmless jellyfish, a dangerous jellyfish may accidentally swim in after a strong wind or storm. Therefore, it is worth preparing your family members in advance for the fact that you cannot pick up jellyfish.
Jellyfish habitat: warm waters of the Mediterranean, Aegean, Black, Caspian, Azov, Red Seas, Indian Ocean, Amur Bay (Vladivostok).
Particularly dangerous jellyfish:
Tunisia (Mediterranean Sea) - black jellyfish, Canary Islands - Portuguese man-of-war
Coast of the Black, Caspian and Azov Seas - jellyfish cornermouth
Precautionary measures:
- plan in advance and choose safe seasons (for example, during the rainy season in Asian countries, the number of jellyfish near the coast increases, August and September are jellyfish season in Tunisia),
- do not swim in the sea immediately after a storm, do not touch jellyfish with your hands.
In case of defeat:
- Do not wash the wound (burn site) with sea or fresh water - this can lead to an even greater spread of the poison.
- It is necessary to lubricate the skin with vinegar solution or alcohol, remove remnants of the jellyfish from the skin, treat the wound with wound-healing ointment, and also take antihistamines.
Sea urchins
Sea urchins can be found in warm seas on sandy bottoms, on rocks, cliffs in the sea or on coral reefs. They often form large accumulations on sloping rocky surfaces near the shore, can be found on metal stairs when descending into the water, and grow on piers and bridges. Unlike other sea inhabitants, the urchin's spines do not contain poison. However, its injection is very painful and can take quite a long time. There is also a high risk of wound suppuration or healing with remaining needles inside.
Sea urchin habitat: warm waters of the Mediterranean, Aegean, Red Seas, Amur Bay (Vladivostok), Indian Ocean.
Particularly dangerous:
Sea urchin tiara , upon contact with which paralysis may occur.
Precautionary measures:
- be careful when entering water where there are accumulations of stones,
- Do not swim in muddy water or in the dark.
In case of defeat:
- If a sea urchin needle gets into your leg, you should contact a medical facility as soon as possible.
- If there is no such thing nearby, then you can try to remove the needle yourself, after first holding the affected area in hot water and treating it with alcohol.
- In Greece, sea urchin spines are removed as follows: the wound is lubricated with olive oil and the spines are squeezed out.
Octopuses
The word “octopus” or “octopus” has been a metaphor for something dangerous and frightening for almost 200 years. Cases of attacks by huge three-meter octopuses on people have been described in fiction. In fact, there are only a few actually confirmed such cases.
The huge octopuses described in the novels of Victor Hugo live at great depths and do not attack people themselves, but rather hide from them. Divers have been known to encounter such octopuses in the holds of sunken ships or in underwater caves. Therefore, if you decide to scuba dive, avoid such places.
Small octopuses that live in the Red or Mediterranean Sea, as well as in the Indian Ocean, pose a danger only if you pick up the sea animal. The octopus has jaws similar to the beak of a parrot, which, when bitten, release poison that can cause paralysis and suffocation.
Octopus habitat: Mediterranean, Aegean, Red Sea, Amur Bay (Vladivostok), Indian Ocean.
Particularly dangerous:
Blue-ringed octopus - lives in Japan and Australia and causes severe paralysis of the entire body.
Precautionary measures:
- do not handle octopuses,
- do not swim into underwater caves and grottoes.
- If you are scuba diving, be sure to have a sharp knife with you so that if an octopus attacks, you can cut its dexterous tentacles.
In case of defeat: Since an octopus bite can cause paralysis and suffocation, you need to urgently call for help and call an ambulance. Experienced fishermen recommend urinating on the bite site, this way the poison can be neutralized.
Sharks
Until recently, Russian seas were considered practically safe in terms of the likelihood of shark attacks on people. However, in 2011, white sharks began to attack divers near Vladivostok, 10 meters from the shore. In 2016, as well as in May 2017, sharks dangerous to humans were also spotted in these areas.
Shark habitat: The Black, Azov and Caspian seas are considered the safest due to desalinated water and pollution. Mediterranean Sea(resorts of Greece, Turkey, Italy, Croatia, Cyprus, France) - over the past 100 years, 21 cases of fatal attacks have been recorded. The most likely inhabitants are the tiger shark, mako shark, hammerhead shark and gray reef shark.
Red Sea (Egypt, Israel): There are about 30 species of sharks, some of which come close to the shore. Attacks by especially dangerous white and tiger sharks are possible.
Indian Ocean: Most attacks were recorded near the coast of Australia and Africa, South Africa (Kosi Bay). The gray, tiger and great white sharks that are dangerous to humans live here.
Atlantic Ocean and Pacific Ocean: beaches near California, Florida and Hawaii are considered the most dangerous with the highest numbers of sharks.
Particularly dangerous:
Great white shark (man-eating shark) is one of the largest and most dangerous predators, reaching five meters in length. It lives in all seas and oceans, including Primorye and Sakhalin.
Mako shark (blue-gray shark) - the fastest and most aggressive shark in the world. It lives in almost all seas, including the eastern region of our country in the summer (with the exception of the Black, Azov and Caspian). Numerous cases of attacks by this shark on people standing on the shore or on the pier have been recorded.
Blue shark (blue shark) - There are a few known cases of attacks on people. Inhabits all seas and oceans, including Kamchatka.
Tiger shark - one of the most dangerous species of sharks for humans. In 2011, 169 cases of this shark attacking people were recorded, 29 of which were fatal. Lives in tropical and subtropical waters (Red Sea, India, Australia, North and South America).
Precautionary measures: The main reason for shark attacks on people is the shark’s poor vision; it mistakes a floundering person for a fish. Vacationers often provoke the shark themselves and swim closer to it. They even came up with such dangerous entertainment for tourists as swimming with sharks. Those who choose this method of “relaxation” forget that sharks are predators, and they can react to bright swimsuits, jewelry, as well as fresh wounds or cuts on the body, since they sense blood over long distances.
Do not swim alone, especially near schools of fish, fur seals, and dolphins. Sharks love loners and most often attack solo divers. For safety reasons, modern repellents and repellents have been created as a means of protection against sharks.
In case of meeting and defeat:
- If you are swimming and see a shark in the water, do not tease it, but catch a wave and try to go ashore.
- Sharks will even attack a person in a boat (for example, a mako shark), so if you are in a boat and a shark swims towards you with the intention of attacking, you need to hit it on the nose with an oar and immediately swim to shore. This will scare away the shark and buy time.
- Try to overcome panic and fear: the shark feels fear, this can provoke an attack.
- When meeting a shark, you need to swim away slowly, without rushing and without floundering in the water, but you should not pretend to be dead, since this method does not work with sharks.
- Just because a shark is just swimming by doesn't mean it wants to attack.
- A possible shark attack is indicated by the shark heading straight towards you or circling around you.
- As a rule, the shark attacks in one sharp movement, it is at this moment that you can strike back at it in the nose, eyes and gills.
- The blows must be struck quickly and many times, everything in your hands will be useful. For example, a camera, a mask, fins, a stick, a stone.
- If there is a large rock nearby, you can press yourself against it. This will reduce the angle of attack of the shark.
- If a shark attacked and swam away, then you need to call for help as quickly as possible and get ashore - the predator may return.
Sea fish
The most dangerous and poisonous sea fish live in the Indian Ocean and the Red Sea, where tourists are invited to scuba dive and observe the beautiful underwater world. However, it is worth remembering that no matter how beautiful the fish are, you cannot touch them.
The most dangerous and poisonous fish of the seas and oceans
Spiny Arotron (relative of the deadly Fugue fish) - releases powerful poison — tetrodotoxin can cause death. Lives in the Red Sea, Indian Ocean.
Lionfish (Lionfish) — The fins of this beautiful fish contain needles that emit poison that causes severe pain and paralysis, and can cause death. Found in the Red Sea and Indian Ocean.
Arabian surgeon - This fish's tail-spike contains a dangerous poison, very painful. Lives in the Red Sea and Indian Ocean.
Stonefish (wartfish) — the poison secreted by its thorns is very dangerous, causes unbearable pain, leads to paralysis, tissue death and, if deeply penetrated, can cause death. Lives in the Red and Mediterranean seas.
Scorpionfish, sea ruff - sea ruffe injections cause very severe pain. It lives in the waters of the Mediterranean Sea and the Atlantic Ocean.
Stingray - The stingray spine, which can be stepped on, contains poison. The prick of a thorn is extremely painful and dangerous, and can even cause death. It lives in the Mediterranean Sea, as well as in the Black and Azov Seas.
Dangerous inhabitants of the seas and oceans
|
Name of the sea |
Jellyfish |
Sea urchins |
Octopus |
Sharks |
Dangerous sea fish |
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Black(Resorts of the Krasnodar region, Ukraine, Crimea, Abkhazia, Georgia, Bulgaria, Turkey) |
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Azovskoe(Russia, Ukraine, Crimea |
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Caspian(Kazakhstan, Azerbaijan, Dagestan) |
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Amur Bay(Primorye, Vladivostok) |
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Aegean(Greece, Türkiye) |
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Mediterranean(Greece, Spain, Italy, Cyprus, Malta, Morocco, Egypt, Monaco, Tunisia, Turkey, France, Croatia, Montenegro) |
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Red(Egypt, Israel, Jordan, Saudi Arabia) |
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Indian Ocean(India, Sri Lanka, Australia, Indonesia, Africa, Madagascar Seychelles, Maldives, Mauritius Thailand) |
Many marine inhabitants are mistakenly considered deadly to human health and life. But who, in fact, is the real threat? In most cases, people suffer from sea creatures due to their carelessness and excessive curiosity. It's time to find out who you should stay away from.
And so: the 8 most dangerous sea creatures for humans.
Portuguese Man of War or Physalia- this is a colony of modified polyps and jellyfish, which, being closely and mutually connected, have all the features of a single organism. They are usually found near the coast, but in the warmer months of the year they also readily drift towards the earth's poles. The Portuguese Man of War is very dangerous - its poison acts quickly and reliably.
Box jellyfish or Australian sea wasp has long been famous as one of the most deadly marine animals that lives off the coast of Australia. Having a large number of poisonous tentacles, it is a deadly weapon for all living beings. If a person falls into a group of sea wasps, then he has practically no chance of getting to the shore alive.
Blue-ringed octopuses- one of the most dangerous inhabitants of the underwater kingdom. Usually a person can disturb a blue-ringed octopus only by accident, but it will not forgive such clumsy behavior and will calmly reward the offender with a fatal bite.
Great white shark , living in cold coastal waters, it is less dangerous to humans than other poisonous creatures of the seas. But there are still rare cases of white shark attacks on people, especially fishing boats.
Lionfish- striped tropical fish with poisonous spines on their back. The bright color warns everyone that the fish is poisonous. Lionfish or zebra fish cause a lot of trouble for fishermen.
Great barracuda- a predator of coral reefs, up to two meters long. The barracuda has a large number of sharp teeth, which are located both inside and outside its jaw. These fish often follow divers simply out of curiosity, but attack very rarely. True, if this happens, then death is guaranteed.
Millepora- very poisonous fire corals with an attractive appearance for inquisitive individuals. Upon contact with them, a person receives a severe burn, which then develops into an ulcer. Although it is not fatal, the burn can cause severe shock and loss of consciousness.
Wart or stone fish- one of the most dangerous fish on the planet, living at the bottom of the sea in tropical latitudes. Having fairly large poisonous spines on its back, it poses a mortal threat to humans. Since the stonefish often likes to rest in shallow waters, people receive a terrible dose of poison when they accidentally step on it.
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When we go on a summer vacation to some exotic place where there is a sea, a beach and a friendly sun, we rarely think about what dangers may await an unwary traveler in a completely different geographical zone, where the animal world developed completely differently.
If you ask people “What can happen when swimming in the sea?”, the majority will name sharks and random convulsions, which can lead to drowning, as the main dangers. However, many do not even realize how inventive our nature is in terms of killing living organisms.
We have prepared for you the top 9 most dangerous animals living in sea water, many of which are captivating with their harmless appearance, but are capable of killing a person in a matter of minutes.
1. Blue-ringed octopuses
This seemingly cute cephalopod rarely reaches a size of more than 20 centimeters and lives mainly in the coastal waters of Australia. The bright unusual color of the animal can easily attract the attention of amateur divers. But if you decide to cuddle your baby with your hands, then you should know: this is one of the most poisonous animals on the planet, and, possibly, in our solar system.
The venom of the blue-ringed octopus contains a cocktail of toxic substances, including tetrodotoxin, one of the most powerful naturally occurring nerve poisons. One such animal's body contains enough lethal fluid to kill nearly three dozen healthy adults in a few minutes. The bites of this small creature themselves are almost painless and the victim may never understand what caused the sudden illness. There is no antidote; a person can only be saved by immediate resuscitation and connection to an artificial respiration apparatus.
2. Cone snails
One of the favorite pastimes of romantics is to pick up a beautiful shell at the bottom, place it against your ear and listen to the sound of the sea. But sometimes it is better to be a sane person and stay away from such ideas. Especially if you are vacationing in the Australian region.
Cones are one of the most beautiful mollusks in nature. These gastropods got their name because of the shape of their shell. However, do not let their beauty deceive you, because some species of these snails are among the most dangerous animals for humans.
The cones have teeth in their mouths that are shaped like a harpoon. Sensing movement at a close distance, the snail shoots the harpoon forward with incredible speed and digs into the body of its victim, injecting toxic poison that almost instantly paralyzes the mollusk's future dinner. People who inadvertently step on shells in coastal waters or pick them up because of their beautiful appearance are also subject to cone bites. According to biologists, death from bites of some types of mollusks can occur in just two minutes.
Statistics show that cones, on average, kill more people per year than sharks. In general, watch your step if you are brave enough to swim in Australian waters.
3. Stone fish (Wart)
This beast got its name because of its ability to disguise itself as stones among coral reefs. The fish is distributed throughout the southern tropics: it can be found off the coast of Indonesia, the Philippines, Australia and even Turkey. So if you like to take a trip to Hurghada with your family in the summer, then keep in mind that the sandy beaches of even the most luxurious hotels do not guarantee you complete safety in the water.
The stonefish not only looks scary, it is also deadly poisonous. According to most biologists, this is the most poisonous fish on the planet. The creature's back is covered with a number of sharp and durable spikes that can easily pierce light shoes. Each thorn is filled with a toxin, the entry of which into the human body causes incredible pain and suffering. According to eyewitnesses, the suffering of those stung is so severe that they are ready to amputate their own injured limb. Under certain circumstances, a person’s death from wart poison can occur within 2-3 hours.
Even if the victim was saved from death, he may experience chronic suffering for several months or even years. The wart also deserves a place in the ranking of the most dangerous animals.
4. Lionfish
Continuing the topic of poisonous fish, we cannot ignore another species, which, despite its mesmerizing beauty, can cause the death of a person.
Lionfish are common in the coastal waters of Japan, India and Australia. Individual individuals of these creatures can reach sizes of 30 centimeters. Unlike warts, lionfish have a bright color that is visible under water even from a great distance.
The fish got its name because of its large wing-like fins. The main danger of this beauty lurks in these fins: the creature’s body is simply studded with poisonous spines, the injection of which will not only result in incredible pain for a person, but can also cause death due to paralysis and respiratory arrest. Even after receiving a non-lethal dose of poison, the victim may simply choke on water due to convulsions.
5. Sea snakes
Oddly enough, many people do not know that sea snakes are one of the most poisonous animals on the planet. Perhaps this is due to the fact that there are not so many victims of the bites of these creatures. However, these creatures belong to the asp family, and their venom can be compared in its toxicity to that of taipans and mambas.
Sea snakes are common in the tropical Indian and Pacific oceans. These reptiles like to stay near the shore, so the chance of meeting them at an exotic resort is very high. The character of these animals is quite calm, and they use their poisonous fangs only in self-defense and hunting. But if a bite does occur, then in the absence of qualified assistance, a person’s death can occur quite quickly.
The venom of sea reptiles is much stronger than that of their land-based counterparts, because its task is to instantly infect cold-blooded animals whose blood circulation is slow. The main thing is not to provoke snakes into aggressive actions.
6. Irukandji Jellyfish
Perhaps one of the most underestimated creatures in terms of danger among ordinary people are jellyfish. At many resorts you can meet people who casually take pictures with jellyfish in their hands, not even realizing that such a photograph could become a dying photo.
The Irukandji jellyfish is evidence that marine life is best observed from afar. This is an extremely poisonous creature that was named after a real tribe in Australia.
At first glance, the animal does not cause concern. It looks like a small bell, about 2 centimeters in diameter, with long, up to 1 meter, tentacles that flutter gracefully in the water. But the tentacles of a jellyfish are covered with special stinging cells, each of which has a small flagellum on which there are villi. As soon as you touch the jellyfish’s tentacle with your hand, it immediately “sticks” to the skin, the stinging cells “explode” and the flagella dig into the flesh of the victim.
The pain from a jellyfish sting is simply monstrous. Without timely medical care, there is a high probability of death even for a strong, healthy person.
If previously jellyfish were common only off the Australian coast, then due to global warming they can now be found in the waters of the entire world's oceans.
7. Sea wasp
Continuing the topic of jellyfish, we will have to mention one of the most dangerous animals in the world. Meet the box jellyfish sea wasp. Nothing unusual, just a jellyfish that can kill more than fifty healthy adults in a couple of minutes.
The size of the dome of this box jellyfish is quite large - up to 25 centimeters, and the tentacles extend up to 3 meters. However, the creature is almost transparent and it is quite difficult to see it in the water, which may result in accidental contact with a person who decided to swim in the coastal waters, or was simply walking in the water near the shore.
Almost always, physical contact between a person and a sea wasp is lethal. There are legends about the poison of this creature. The toxin in the cells on the tentacles of the jellyfish is so strong that doctors recorded deaths after just 4 minutes from the moment of the burn. Often, people stung while swimming do not even have time to reach the shore.
The box jellyfish sea wasp has become a symbol of mortal danger. She even starred in the famous drama “7 Lives,” where the main role was played by Will Smith, whose character chose the fastest way to die - getting burned by a box jellyfish.
8. Sea cat
Compared to the previous killers in our top of the most dangerous animals of the deep sea, the stingray (Sea Cat) does not look so terrifying. However, because of the poisonous spike at the end of the tail of this creature, thousands of people suffer every year, who, through their carelessness, disturb the stingrays, or pick them up.
Most often, a sting from a stingray is not fatal, but there are exceptions. For example, in 2006, the famous Australian naturalist Steve Irwin, the “crocodile hunter,” died from an injection. As the zoologist swam over the stingray, the animal twisted and hit Steve with its spike directly in the chest. The blow was so powerful that the spike pierced the man’s heart, causing instant death.
9. Stinging corals
Yes, these corals also belong to the animal kingdom. The scientific name of such creatures is millepora, and it is quite difficult to distinguish them from simple corals, especially considering that they settle directly on coral reefs.
The body of these animals has a defense mechanism against predators that resembles the principle of action of nettle hairs, but with more serious consequences from burns. Divers love to chop off a piece of coral as a souvenir, or simply touch an unusual curiosity under water, and can pay a lot for it. According to the stories of victims, the burn from touching such corals can be compared in pain to a burn from hot metal.
In general, the venom of this creature is not fatal, but the painful shock under water can cause convulsions, uncontrolled breathing reflex and drowning.
Not all dangerous sea animals are included in this list. Even more secrets are kept by the unexplored depths of the oceans, where even mechanical devices created by man rarely look. From all of the above, we can conclude: wherever you go on vacation, no matter how confident in your physical capabilities you are, always be vigilant, take care of your loved ones, and study possible dangers. Even the most poisonous creature is a unique creation of nature, which is interesting to observe from a safe distance, or even better, on the pages of the website.
At the bottom of the ocean we are most vulnerable for obvious reasons. Throughout the history of evolution, humans have not adapted to extract oxygen from water. Any animal with sharp teeth and a strong bite can pose a threat to life. The oceans are filled with deadly animals. The exception is those that do not threaten human life and are dangerous only when they defend themselves, for example, puffer fish.
10. SEA SNAKE
If you ever thought that only land snakes pose a deadly threat to human life, then think again. Sea snakes also have venom that is extremely dangerous to humans. But it is extremely rare that they release venom when they bite their prey. However, if sea snakes inject venom, the consequences can be dire.
When they bite, a small amount of venom is released. The victim does not immediately feel the effect of the poison. Within an hour, symptoms such as headache, swollen tongue and vomiting begin to appear. This is followed by convulsions and progressive muscle paralysis.
After 3-8 hours from the time of the bite, myoglobin begins to appear in the blood. As a result, muscle tissue is destroyed. Kidney failure may also occur. After 6-12 hours (unless treated), severe hypercalcemia can lead to a heart attack and sometimes death.
9. BARRACUDA 
Fast, vicious and capable of causing incredible damage - a terrifying combination for an underwater devil. The barracuda has a long body, like a snake, with sharp, fang-like teeth. Its teeth look and work in the same way as a piranha's teeth. Barracudas grow up to two meters and are known for being fast swimmers. To catch up with their prey, they can reach speeds of up to 45 km/h.
Before biting prey, barracudas calculate its weight. Barracudas have very sharp teeth that can damage nerves and blood vessels. They don't meet people that often. But if a meeting happens, then most likely there will be a bloody clash. Barracudas may well bite off part of a human body. Some barracudas contain poison. Under the influence of the poison, the victim may experience hallucinations and multiple side effects.
8. MUREN 
Moray eels are most often found in the deep ocean. They avoid contact with humans whenever possible and are considered relatively shy creatures.
However, if there is a real threat, moray eels may show that they are not the ones to play with. A moray eel bite can cause an infected wound because their mouth contains a huge amount of bacteria. Moray eels have poor eyesight and rely heavily on their keen sense of smell. Many divers have lost fingers while attempting to hand feed.
7. FISH-STONE 
This small fish species looks unusual. The fish is like a stone, which helps camouflage itself from predators. Unfortunately, anyone who accidentally steps on the fish will encounter sharp spines that can easily pierce bare feet. In most cases, the stonefish stings when it is stepped on and less often when it is lifted.
Stonefish can sting not only in water, but also on land, as they can survive without water for 24 hours. When a fish stings, the victim feels pain due to the wound. She also receives a small dose of a neurotoxin that can block the respiratory system and lead to cardiac arrest. Poisonous, dangerous and destructive fish for people.
6. SKAT 
At first glance, the stingray seems to be a rather passive animal, but it should not be underestimated. The stingray is usually calm, but can sometimes cause serious harm with its sharp tail.
The end of a stingray's tail can sever arteries. The tail contains poison that is extremely dangerous for mammals. Contact with the stringer from the action of the poison causes injury, pain, swelling, and muscle cramps. And then infection from bacteria and fungi may occur. Although the wound is extremely painful, it is not life-threatening until the stingray hits vital organs.
5. TIGER SHARK 
The great shark has become famous for having the widest range of foods among all sharks. It feeds on a variety of prey ranging from fish, seals, birds, squid, turtles to dolphins and even smaller sharks.
The bull shark is quite impressive, but the tiger shark is something else. She does not look for people as food. However, the tiger shark often enters shallow reefs, harbors and channels, posing a potential threat to people.
Sharks rarely attack people, but tiger sharks account for a large percentage of fatal attacks. Thus, they are one of the most dangerous animals in the ocean. And the worst thing is that a delicate sense of smell and strong teeth allow sharks to quickly deal with any prey. And sometimes a person can become an unfortunate prey.
4. GREAT WHITE SHARK 
The majestic name does not convey optimism, but speaks of merciless cruelty. The great white shark is easily recognized by its size. It reaches up to six meters in length and can weigh 3324 kg. Another distinctive feature of sharks is that they attack their prey from below with their mouths wide open and their razor-sharp teeth inflicting maximum damage.
Anyone who has seen the movie “Jaws” should know that these creatures pose a mortal danger to humans. There have been a significant number of unprovoked fatal attacks by great white sharks on humans.
3. SEA CROCODILE 
Always be aware of salty waters. Crocodiles attack when least expected. Saltwater crocodiles are known to have a bite force 10 times greater than that of a great white shark. Unlike sharks, crocodiles can walk on land.
Like most crocodiles, saltwater crocodiles are not picky about their food choices. They select prey based on availability. However, previously saltwater crocodiles killed thousands of people every year. Most cases remain unreported.
During World War II, saltwater crocodiles are known to have eaten more than 400 retreating Japanese soldiers. The soldiers were crossing a river in which there were thousands of crocodiles.
2. BLUE-RINGED OCTOPUS 
Despite its small size, the octopus contains poison that can kill 26 adult men within a few minutes. Their bites are small and often painless. Many victims do not even realize they have been bitten until respiratory depression and paralysis sets in.
Poisoning can lead to nausea, respiratory arrest, heart attack and often complete paralysis. If treatment is not timely, death sometimes occurs. Considering the fact that an antidote for the bite of blue-ringed octopuses has not yet been created, they are one of the most dangerous animals for humans.
1. CUBOMEDUSA 
When it comes to dangers at sea, size doesn't matter. Box jellyfish contain one of the most dangerous poisons on the planet.
Accidentally touching the poisonous tentacles of a jellyfish causes severe pain and a burning sensation, which can lead to death. But the most dangerous thing is that people cannot spot jellyfish because of their transparency before they harm them.
Sea snake rarely bites humans - it uses its venom mainly when hunting and sometimes for self-defense. However, if something goes wrong, a sea snake bite will not be harmless. Their venom is very toxic. The victim does not immediately feel the effect; headache, vomiting and other symptoms appear only within an hour. And after a few hours, myoglobin appears in the blood, destroying muscles. If the necessary measures are not taken, kidney failure and heart attack occur, which can ultimately lead to death.
Barracuda- Swift, ferocious and capable of causing serious injury, this perch fish can seem like a real underwater devil. Long, like snakes, the barracuda has a powerful lower jaw with sharp teeth, like those of a piranha. The barracuda can reach 205 cm in length and reach speeds of up to 40 km/h. It is not surprising that she quickly overtakes her victim. Barracudas do not attack people very often - this usually happens in muddy or dark water, when there is a risk of mistaking a person for a fish. Such a collision does not bode well: a barracuda is capable of tearing out a piece of a human body. If suddenly this doesn’t scare you, know that their body contains a toxin that causes hallucinations and other side effects in humans.
Moray eels, representatives of eels, avoid contact with people. But if they feel threatened, it's all over. An eel bite is dangerous not only because it causes mechanical injury. This moray eel's mouth contains countless bacteria that instantly enter the wound. And if you, while underwater, decide to feed a moray eel by hand, remember - they have poor eyesight, and you can easily say goodbye, if not to your hand, then to your fingers.
Warts, a genus of ray-finned fish, in English they are called stonefish, i.e. “stone fish”, because it can easily pass for a small stone. This helps the fish camouflage well and easily misleads a person who might accidentally step on such a “pebble.” Alas, such an oversight is not painless: the sharp thorns of the wart dig into the foot, and a small dose of the neurotoxin penetrates the human blood, causing problems with the respiratory system and even heart failure. Remember that these fish can be out of the water for up to 24 hours, so keep your eyes peeled and on the shore.
Eagle ray not as harmless as it might seem. It is usually relaxed, but can seriously injure humans with its tail. The fact is that at the base of the tail these stingrays have spines (one or more), the length of which can reach 35 cm. The spine, in turn, is capable of releasing poison. A painful prick with a thorn is fraught with swelling, cramps, and bacterial infection. In 2006, an Australian naturalist and TV presenter was tragically killed by a stingray - a stingray wounded him in the heart, and the wound turned out to be fatal.
Tiger shark has a good appetite: her menu includes fish, seals, birds, squid, turtles, dolphins and even other, smaller sharks. It is not surprising that human remains are often found in the stomach of a tiger shark. It is believed that they do not specifically hunt people as prey, but frequent encounters with humans in the area of small reefs, harbors and channels, however, become fatal for people.
White shark- this is the answer to the question “who can be more dangerous than a tiger shark.” It is also called the “man-eating shark”, and for good reason. The impressive dimensions - about 5 m in length and weight from 700 kg to a ton - leave no chance for humans. White sharks have their own signature style: they attack their prey from below, opening their mouths wide so that their huge, sharp teeth can cause as much damage as possible. Have you seen the movie "Jaws"? This is about them.
Saltwater crocodile, also known as a man-eating crocodile, lives primarily in the Indian Ocean. The force of its bite is considered to be 10 times stronger than that of a white shark. In addition, unlike a shark, a crocodile can lie in wait for you on land. Crocodiles are not gourmets; they do not choose gourmet food for themselves, but eat whatever they can get their hands on. According to one version, more than 400 Japanese soldiers who crossed the river during their retreat during World War II became victims of saltwater crocodiles.
Blue-ringed octopus may seem like an unexpected participant on such a list. Its size does not exceed 12-20 cm, but a tiny and almost painless bite can kill a person within a few minutes. The venom of this octopus is extremely toxic - nausea, respiratory arrest, heart failure, complete paralysis or death: all of this can end your encounter with an octopus if emergency measures are not taken. The danger also lies in the fact that such a minor bite does not cause concern in a person until the first signs of poisoning appear.
Box jellyfish are definitely beautiful. And damn dangerous - after all, they have one of the most dangerous poisons of all living creatures. Deaths due to burns from box jellyfish bites occur every year. The worst thing is that this danger is difficult to control - jellyfish are almost transparent and swim very quickly, which is why there is a high risk of simply not noticing them.
