Jellyfish near the shore are alive or dead. Life in the water column. Tragedy at sea

The sea wasp (box jellyfish) belongs to the class of box jellyfish cnidaria. This multicellular - rare and very dangerous for humans. In nature, there is great amount different but it is considered the most poisonous on the planet. It stings like a well-known wasp, only instead of one sting, box jellyfish have a hundred times more of them. Their poison is death for all living organisms. Over the past century, these predators have killed about a hundred people. If a diver gets into a flock of sea wasps, then he has practically no chance of returning to shore.

Who is called a sea wasp?

IN sea ​​depths hiding a large number of dangerous predatory creatures, many of them have not yet been studied at all. Who is called the sea wasp, who swims up in an invisible shadow and injects a lethal dose of poison? This monster - the box jellyfish - is almost impossible to see in the water, the people call it "invisible death".

You can't call this creature a monster when you see it. These are relatively small jellyfish, shaped like a cube or a bottle. The body is about 5 cm in diameter, although there are rare individuals, in which the dome reaches 20-25 cm. It is better not to meet with such, as this is a real death machine. By the way, the box jellyfish was so named precisely because of the cube-shaped structure of the dome.

The tentacles of the sea wasp deserve special attention, because they are the formidable weapon of the jellyfish. In length, they reach one and a half meters, their number can reach up to 60. If you fall into such a deadly "embrace", then a lethal end is inevitable. Glands are hidden in these long, terrible lashes, so they produce a poison that is stronger than that of a snake.

Scientists cannot figure out another feature of the sea wasp in any way - why does a jellyfish, which has no brain, need eyes, can it see the world? Surprisingly, the box jellyfish really has eyes - as many as twenty-four. These organs are divided into 4 groups of 6 eyes each. With so many, this creature must see?

Where do sea wasps live in nature?

It would seem that a jellyfish can live in any sea ​​water. All the expanses of the oceans and seas are subject to these tentacled miracles, but this false statement. The sea wasp, for example, lives only in Australia. Favorite place marine predators- northern shores, in those waters there is a relatively shallow depth and a large accumulation of corals.

Lifestyle of a poisonous monster

As mentioned earlier, the sea wasp is an active dangerous predator. When hunting, the box jellyfish keeps completely still, but as soon as the prey touches the tentacles invisible in the water, it immediately receives a large dose of poison. Moreover, the jellyfish stings several times in a row so that the victim quickly dies. The poison is very strong, it affects nervous system, on cardiovascular system and damage the skin.

Sea wasps feed on shrimp, small crabs and small fish. The predator pulls the stung prey with its tentacles to the dome and sucks it inward, where it calmly digests.

Box jellyfish hunt in the coastal zone, but keep far from the coast. During a storm or high tide, when the sea is rough and strong waves roll on the shore, these poisonous creatures often go straight to the beaches where people swim.

reproduction

The sea wasp goes through the same breeding stages as other jellyfish. First, predators lay eggs, larvae appear from them, which attach to the bottom and then turn into polyps. Polyps reproduce by budding.

After a certain time, the body of the jellyfish breaks away from the polyp and swims away to create its black deeds in the open spaces of the sea. Without a jellyfish, an abandoned polyp dies instantly.

Can a sea wasp sting?

As mentioned earlier, the box jellyfish poses a great threat to human life. Although we will not make such a bloodthirsty predator out of her, she only attacks what can serve as food. People are not included in this list; when meeting with them, the sea wasp prefers to swim away. It can sting a person, but only by chance, when it does not have time to dodge a collision. Most often, divers are exposed to such danger.

After receiving several doses of the strongest poison, the body instantly begins to react. The skin turns red, the stung feels unbearable pain, from which there is no salvation, the burn site swells terribly. Dizziness, fainting, high fever - these consequences of a meeting with a sea wasp may well end in respiratory arrest and cardiac arrest. Death can occur in the very first minutes after a collision with deadly tentacles, or it can occur in a day. It all depends on the amount of poison injected.

This "invisible death" swims very well, can quickly turn and maneuver between corals and algae, moves relatively quickly under water - up to 6 meters per minute. It is possible to consider transparent predators only in shallow water, the warm sandy bottom is best place for their existence and reproduction. In the daytime, sea wasps stay at the bottom, with the first twilight they float to the surface.

To protect vacationers on the beaches from jellyfish, lifeguards put warning signs along the coast, but unfortunately, this does not guarantee people complete safety in places where sea wasps are found - the most poisonous among jellyfish.

We already wrote that on . Now the waves are throwing dead carcasses of animals ashore, in huge quantities.

Experts link the invasion of jellyfish with temperature changes and ask residents of Odessa to be careful. However, due to the cold snap, the residents of the city do not climb into the water, but simply watch sea ​​creatures from the side. Many of them arrange a kind of flash mob on social networks, where they post photos of jellyfish of different colors and sizes.

“I often ride a bike to the Seaport,” said Nastya, a young Odessa woman. Lately I noticed a lot of jellyfish. From the outside, they look intimidating and bewitching at the same time.

beautiful, strange creatures are called cornerots (Rhizostoma pulmo). Such jellyfish usually live in Atlantic Ocean including the Mediterranean and Black Sea. In August-September they usually approach the shore.

Jellyfish love cold water, their largest concentrations are observed in the Irish Sea, where the water is cold. Also, their clusters can be found off the coast. South Africa where the cold Bengal current passes.

This type of jellyfish can cause burns in humans. Touching the tentacles causes a sensation similar to a nettle burn. Jellyfish mucus is also toxic. After touching the jellyfish with your hands, in no case should you touch your eyes, lips and nose. The burn site must be immediately washed with water, preferably fresh.

Jellyfish

Ctenophores are living rainbows

Why jellyfish swim to the seashore, you will learn from this article.

Why do jellyfish swim to shore?

Jellyfish swim to the shore to leave offspring. Their total invasion in shallow water, closer to the coast - this is just a temporary phenomenon. Having taken care of their future, they swim back deep into the depths of the sea.

Why are there many jellyfish in the sea?

There are not always many jellyfish in the sea, but often the coast is overflowing with such inhabitants. This means that jellyfish have a mating season

Jellyfish are one of the most ancient inhabitants of our planet. They appeared more than 650 million years ago. And in the process of evolution, they have changed little. 95% of these animals are made up of water, and 5% of the muscle fibers in their body makes jellyfish a complete organism.

Three types of jellyfish can be found in the sea:

• Aurelia

It is also called "eared jellyfish". And all because there are transparent white tentacles around the entire circumference of the aurelia. This is the most small view jellyfish A feature of the animal is the presence of stinging cells in the body, which can damage the edges of the lips and the mucous membrane of the eyes.

• Cornerot

By appearance it resembles a fleshy bell or dome with a heavy beard from the oral cavities. Lacy blades are equipped with poisonous stinging cells. It is better to swim around such jellyfish.

• Mnemiopsis

This type of jellyfish does not have stingers or tentacles. In the Black Sea, it is the smallest. Its feature is the ability to glow. Therefore, another name for Mnemiopsis is nightlight.

Another book by biologist Lisa-Anne Gershwin shocked American readers

Following Greenpeace activists, scientists are sounding the alarm: the growth of the jellyfish population in the oceans around the planet is an indicator that something is out of balance. Jellyfish numbers have skyrocketed over the past few decades and are a sign of the deteriorating health of the planet's marine ecosystem, says biologist Lisa-Anne Gershwin. Together with thousands of frightened Americans, the MK columnist read the book.

My acquaintance with jellyfish is very superficial. It's the surface. When they appeared on the surface of the water off the coast of the Black Sea on Zeleny Mys in Adzharia, where our family usually spent their holidays, we boys caught them, threw them on the hot stones of the beach and, as if spellbound, followed their gradual melting. Did we know then that the day will come when jellyfish and people will change places, and already jellyfish will watch how homo sapiens dies.

Personally, I learned about this by reading Dr. Lisa-Anne Gershwin's book Stung on Jellyfish Bloom and the Future of the Ocean.

Now in America, as in Russia, it has become fashionable. It is argued that watching these hypnotic beautiful creatures contributes to the nervous relaxation of a person who has been hunted by the topic of the day. Don't know. Haven't tried. But I know that these beauties know how to sting more than any coquette. Some only slightly, others to death. In the north of Australia there are the most poisonous jellyfish on the ground. Their Latin name is Chironey fleckeri. The Americans dubbed them box jellyfish (Box jellyfish).

The bell of these jellyfish is one foot in diameter. But behind him is a trail of tentacles, 550 feet long. It is in the tentacles that the sting cells are located. If even six yards of these tentacles touch your skin, then you have two or three minutes to live. Australia has recorded 76 deaths from such touching. There are many more unregistered.

In 2000, this breed of jellyfish almost blew Olympic Games in Sydney. Darkness of jellyfish swept just at those places where water competitions were supposed to be held. The organizers of the games were stumped. All proposals to get rid of jellyfish proved to be unworkable. But the Olympians were lucky. On the opening day of the games, the jellyfish disappeared as mysteriously as they appeared.

Most jellyfish small size, like sachets of gelatin, containing the digestive organs and field glands. But box jellyfish are very different from them. Let's start with the fact that they are jellyfish hunters. They prey on medium-sized fish and crustaceans. They are mobile for jellyfish - they move more than 6 meters per minute. They are the only of all types of jellyfish that have eyes, and very sophisticated. And they have the ability to learn, remember and perform other complex actions.

Such jellyfish, but smaller, are called irukandzhi. For the first time their description was made by scientists in 1967. Apparently their exotic name comes from the linguistic roots of the Aboriginal people living in North Queensland. Aborigines have been familiar with the poisonous Irukandji for thousands of years. Europeans had the honor to meet them in 1964, when Dr. Jack Baris, in the best traditions of the Aesculapius, decided to test the effect of their bites on himself. (The inhabitants of the coastal regions of Queensland suffered from them). The doctor miraculously survived.

A touch, even the lightest, of the tentacles of these jellyfish causes the so-called. The affected area may be minimum dimensions and the stung may not even feel anything. But after 20-30 minutes he starts having strong contractions and aches. The pain is like being hit in the kidneys with a baseball bat. Then comes vomiting, which lasts all day. Spasms fetter the arms and legs, blood pressure rises greatly; breathing becomes difficult; the skin takes on the appearance of being perforated by hundreds of worms. Victims ask doctors not for salvation, but for euthanasia. A person dies either from high blood pressure or from a heart attack. If he was at that time in the water, then he drowns. The threat from the Irukandji is growing from Cape Town to Florida.

But, so to speak, poisonous and stinging jellyfish are just "flowers", and it is not their poison that poses the main threat. environment and humanity. In his book, Doctor of Biology Gershwin writes that after 500 million years of “staying in a slumber”, jellyfish lived and went on the offensive. Gershwin states: “What would you think if I presented you with evidence that jellyfish have displaced and replaced penguins in Antarctica right now? That jellyfish are able to finish off fishing, defeat tuna and swordfish? To starve out the whales themselves? Will you believe me?" We, ignorant, are unlikely to believe Dr. Gershwin, who writes such horror stories about jellyfish. But, unfortunately, she is right. Experience and science are on her side.

Jellyfish are one of the oldest inhabitants of our planet. 550 million years ago, they were almost the only inhabitants of the oceans. Today they are forced to share aquatic environment with myriads of other waterfowl and with the creations of human hands. In November 2009, nets full of giant jellyfish weighing up to 450 pounds overturned a Japanese trawler. His crew drowned. But even larger ships are victims of jellyfish.

July 27, 2006 modern American aircraft carrier"Ronald Reagan" moored in the port of Brisbane in Australia. The Australians, following the example of New Zealand, also decided to ban the entry into their ports of ships operating on atomic energy. However, from Brisbane "Ronald Reagan" was expelled not by people, but by jellyfish. Thousands of jellyfish sucked into cooling systems nuclear engines aircraft carrier. The ship was paralyzed. "Jellyfish have captured an American aircraft carrier!" shouted the headlines of the Australian newspapers. The crew of the ship came to the rescue, "just in case" local fire brigades. Residents of the city, with bated breath, watched the duel of an aircraft carrier with jellyfish. But the fight was unequal. The aircraft carrier was forced to leave the port.

However, that aircraft carriers! Entire countries may be captured by.

In December 1999, 40 million people in the Philippines suddenly lost their electricity. The president of this country, Joseph Estrada, was extremely unpopular, and many decided that there was a coup in the country. This news spread all over the world. But after 24 hours, the real culprits of the blackout were discovered. They were jellyfish. They clogged the cooling system of the most important power plants and put them out of action. Rescuers raked out a huge number of jellyfish for the export of which took 500 giant trucks.

The invasion of jellyfish has been constantly subjected since 1960 to Japanese nuclear power plants. An average of 150 million tons of jellyfish were raked out from only one of them daily.

Gershwin writes: “Jellyfish are amazing at sucking. Imagine a piece of thin plastic wrap in a pool that can stay on the surface for the rest of the century without going to the bottom. Until he clogs the water outlet." Chemicals here are powerless, as well as electric shock and acoustic machines. Actually, even killing jellyfish does not solve the problem. Whether alive or dead, they continue to be absorbed. Admirals and power plant owners lose many millions of dollars forced to shut down their charges.

Jellyfish are capable of destroying entire ecosystems. It was such a catastrophe that happened when the jellyfish belonging to the species Mnemiopsis (Mnemiopsis), invaded my native Black Sea. They were brought in by American ships along with water pumped into them instead of the delivered cargo! Water ballast to keep the boat stable on the water. By the 1980s, jellyfish had taken over the Black Sea, decimating the fisheries of Georgia, Bulgaria, and Romania, and attacking anchovies and sturgeons. With the increase in the number of jellyfish in the Black Sea, these precious fish have disappeared.

By 2002, the weight of Mnemiopsis jellyfish in the Black Sea was ten times greater than the weight of all the fish caught in one year worldwide. In fact, the entire Black Sea, so to speak, has become jellyfish. Scientists name four hypotheses that may have led to this disaster. The first hypothesis says that jellyfish overcame their rival anchovies by eating their caviar and plankton. The second hypothesis: jellyfish, eating anchovies, starved them to death. The third hypothesis: there were too many nutritious foods for jellyfish in the sea. And finally, the last hypothesis: climate change has led to the destruction of plankton and the reproduction of jellyfish.

The only salvation from the invasion of Mnemiopsis is provoking " civil war» among jellyfish. Against Mnemiopsis, beros jellyfish are released, which have something like teeth. This helps them eat Mnemiopsis. So, only jellyfish are able to stop the invasion of jellyfish, and even then only partially. And then, horseradish beros is not sweeter than miemiopsis radish.

Jellyfish. And disaster follows them. In 2000, Australians discovered jellyfish in the Gulf of Mexico. They were also brought along with water ballast. Jellyfish in the Gulf of Mexico weigh up to 15 pounds. In 2000 they covered 60 square miles of water. They consumed so many fish, eggs and plankton that it became impossible to maintain marine ecosystem. They ate ten times more than was typical for the Gulf of Mexico. By releasing a substance similar to foam, they slowed down the movement of plankton, which then became easy prey.

Then two disasters hit the Gulf of Mexico - Hurricane Katrina and the oil exodus in 2010. While other inhabitants of the sea began to die, jellyfish not only did not die, but even more multiplied. By 2011, they had penetrated the Mediterranean. On average, 10 people fell ill from their “bites” per day. Had to close a lot tourist beaches at the height of the season. Meanwhile, jellyfish crept up to the shores of Israel and Brazil.

The invasion of jellyfish took on a planetary character - from the Arctic to the Antarctic. There is, as scientists say, "jellyfishing" of the oceans. Off the coast of South Africa, a huge number of jellyfish created what was dubbed the "curtain of death" or "field of death." It's about about a body of water of 30,000 square miles. Once upon a time, intensive fishing took place in these places. About a million tons of fish were caught annually. But in 2006, 3.9 million fish biomass already accounted for 13 million jellyfish biomass. They, among other things, block the vacuum pumps that are used to extract diamonds from the seabed.

Jellyfish are very different. In size - from one millimeter to giant ones, the bell of which is one meter diagonally, and weighs half a ton. One listing of the names of jellyfish speaks of their diversity. There are "moon jellyfish", "lion's mane jellyfish", "sea nuts", "aquavivas" and even "Portuguese male warriors". The last two species of jellyfish, strictly speaking, are not even living organisms. They are, rather, a collection of various jellyfish, which are called "personalities" in reverse. They only function collectively. Sometimes their bunch is striking in its size, sometimes 150 feet in length. As Gershwin writes, “These creatures are neither individuals nor even colonies. For a century and a half now, the greatest minds in evolutionary biology have been debating what their real status is.”

Why are jellyfish taking over our planet? Dr. Gershwin writes that the answer to this question lies in where they live, how they reproduce, and how… they die. To begin with, they are essentially ubiquitous. Having survived half a billion years, they are still able to survive where few other individuals can exist. They have a very low metabolic rate (normal) and therefore do not need much oxygen. They live quietly in waters where other inhabitants of the oceans would suffocate. Some jellyfish "breathe" oxygen with their "bells". Therefore, they can dive into oxygen-free water depths, as divers do, and stay there for up to two hours.

The ability of jellyfish to reproduce cannot but cause surprise. This is the result of their evolutionary success. Perhaps the fastest breeding Mnemiopsis. Scientists call their reproduction "self-fertilization of heromaphrodites". This means that such jellyfish do not need a partner, nor do they need a sex change. They have both genders. Jellyfish start laying eggs as early as 13 days of age and soon lay 10,000 eggs a day. Even if you cut into pieces such jellyfish, you will not be able to stop their reproduction. The quartered jellyfish regenerates and begins "normal life" again. This "revival" occurs within two to three days.

Jellyfish are gluttons like Gargantua Rabelais. So, Mnemiopsis eats food that weighs ten times its body, and increases in size every day. They do this thanks to a truly fantastic metabolism. Jellyfish put more energy into their growth than the more complex creatures they compete with. Mnemiopsis is not satisfied only with saturation, he behaves like a fox in a chicken coop - having had his fill, he continues to kill his victims. Therefore, it does not matter to the ecosystem whether jellyfish digest food or not. They keep killing as long as there is anything left alive. And it happens with amazing speed. According to one study, Mnemiopsis kill up to 30 percent of the population of small crabs daily. “Jellyfish can eat anything. They do just that,” writes Gershwin. (Like the fabulous Robin-Bobbin-Barabek). Some jellyfish do not even eat their victims, but absorb dissolved organic matter through their photosynthesis.

Finally, the question of the death of jellyfish. Bringing death to everything, they themselves are essentially immortal. In "hard times" they simply decrease in size, but their bodies do not lose their proportions, as happens with starving fish or people. If food reappears, jellyfish begin to grow again. Some jellyfish live up to ten years. But in the polyp stage they are immortal. So one colony of polyps, which began to be studied back in 1935, still lives for its own pleasure in one of the laboratories in Virginia.

Despite such amazing biology the population of jellyfish began to exist within the framework created over half a billion years in the water elements, where other creatures wound up. So why are the jellyfish "broke off" now? In the second part of his book, titled with black humor "Jellyfish, Planetary End and Other Little Things", Gershwin will try to answer this question and at the same time predict the future of the oceans, the Earth and mankind.

The author details how other living beings made great efforts to stop the onslaught of jellyfish. The most important component of these efforts was a complex ecosystem with many predatory fish and other competitors of jellyfish. Disturbance of this ecosystem, mainly by humans, plays into the hands of jellyfish. Let's take the Black Sea as an example. Intensive fishing for anchovies, the sworn enemies of jellyfish, has led to the fact that the jellyfish "unbelted". A similar situation is observed off the coast of South Africa. Man went too far not only with catching anchovies, but also with the fishing of almost the entire oceanic fish world. The collapse of many ecosystems "untied the hands" of jellyfish.

Add to that the abuse of our civilization plastic bags and other plastic products, http://oren..html methods of predatory fishing, destruction sea ​​turtles, which in turn destroyed the jellyfish, and it will become clear that we are the main accomplices of the jellyfish, so to speak, collaborators. We create jellyfish nurseries with our piers and docks, marinas and ships, gas and oil platforms at sea, industrial waste and just garbage in water bodies. We have literally littered the oceans with everything that jellyfish polyps are so “in love with”.

And then there's the problem of oxygen in the water. This oxygen is created by algae using photosynthesis. High level oxygen contributes to the struggle of fish and other waterfowl with jellyfish. But the oxygen in the water dries out faster than it is replenished. Therefore, when a person clogs water bodies, for example, with enrichment waste from farms, he contributes to the creation of “entropic zones” with a lack of oxygen. This happens both naturally and artificially, when people pollute water bodies with waste, as, for example, in the Baltic and Black Seas, or in the Gulf of Mexico. "Entropic zones" are spreading at an alarming rate. No individuals that need even a moderate amount of oxygen are able to live in these zones, neither fish, nor crabs, no one, but jellyfish thrive there too!

Climate change also plays into the hands of jellyfish (lucky ones!). Warming ocean waters contribute to the reproduction of tropical jellyfish. And the jellyfish themselves are accelerating climate change. This happens in two ways. First, jellyfish release carbon-rich excrement and mucus. They turn them into a kind of factory for the production of carbon dioxide. Secondly, jellyfish absorb a huge amount of diverse plankton that migrate vertically in the water. It feeds on carbon-rich food on the surface, and excrement goes to the seabed. Thus, plankton is the main means of extracting carbon dioxide from air and water. When their destruction by jellyfish takes on a huge scale, it starts to affect climate change.

And another misfortune is the oxidation of ocean waters. This happens when ocean waters absorb carbon dioxide. The speed of this process is evidenced by the following fact: now the oceans of our planet are 30% more oxidized than 30 years ago. Crustaceans suffer from this. This is how oysters disappeared from the American Northwest. Crustaceans have disappeared in the Arctic and Antarctic. Without "shells" jellyfish are better protected from acids, and the crisis of ocean acidification does not bother them.

Dr. Gershwin writes that jellyfish are taking over the oceans "bit by bit." She believes that this is an irreversible process. A new balance of power is emerging, dominated by jellyfish. “We are creating a world,” says the author, “more like the Precambrian era than the late 1800s, a world dominated by jellyfish and organisms with shells did not yet exist. We are creating a world in which a person will soon not be able to exist, and is unlikely to want to.

Is there a way out of this terrible dying? Yes, Gershwin replies. We must eat those who eat us. According to ancient Chinese texts, jellyfish have been on the human menu for 1700 years. Currently, the global harvest of jellyfish is 321 thousand tons. Their main consumers are China and Japan. If we do not develop an Asian appetite, we are doomed to perish, the author argues.

The United States has already realized the threat of jellyfish. Back in 1966, Congress passed the Jellyfish Control Act. It was updated in 1970 and 1972. The law obliges the Minister of Commerce to conduct studies to determine the number of jellyfish and their effect on fish. True, the financing of this law is ridiculously scanty - only 1 million dollars. Much more grandiose sums are spent on the destruction of mankind.

Here is how the final chord of Gershe's book sounds:

“When I started working on this book, I still had the feeling that the problem could be solved. But I seem to have underestimated the terrible damage we have done to our oceans and their inhabitants. Now it seems to me that we have gone too far and passed the line of irreversibility, not knowing where and when this irreversibility began. It will be oceans without coral reefs, without mighty whales, without staggering penguins, without lobsters and oysters. And with sushi, but without fish. So adjust!" After the gourmets, our turn will come, the turn of ordinary homo sapiens. And the coast of the Black Sea on the Adjarian Green Cape appears to my imagination. But it is no longer us, boys, catching jellyfish and throwing them on the hot stones and sand of the beach and, as if enchanted, look at their gradual melting, but the jellyfish themselves perform this ritual with us, watching with curiosity the disappearance of the human race.

Malor Sturua, Minneapolis