The sea wasp (box jellyfish) is a deadly sea monster. When the living envy the dead. The Raft of Medusa. Teodoro Gericault Why are aurelias near the shore in the heat

And now - let's take our eyes off the bottom and look around the turquoise water column - many marine animals spend their entire lives in it, trying not to get close to either the bottom or the surface. Among them there are magnificent swimmers - pelagic fish, whose whole life is in motion, and slow-moving creatures carried by currents. Of these living floats, we most often encounter jellyfish and ctenophores.

Jellyfish

There are two types of large jellyfish in the Black Sea -aurelia, similar to an umbrella, andcornermouthwith a fleshy mushroom-shaped dome from under which heavy lacy mouth lobes hang. The dome of the cornet can reach 70 centimeters in diameter, the length of such a jellyfish more than a meter! Aurelius appears on our shores early spring, there are many of them in the sea all summer; by autumn, they are replaced by powerful rootworms.

We don't really like jellyfish - they are slippery, and they also sting. That's true. But let's dive in and take a look at them from under the water - how merrily the thin umbrellas of aurelias play in the rays of the sun, like in crystal chandeliers, the light magically splits in the huge bells of the cornerots! From time to time they swing their domes - straighten and contract them, pushing themselves upward. Jellyfish do not know how to move quickly - they are carried across the sea by the will of currents, and sometimes waves wash countless numbers of them to the shore.
Jellyfish live in the water column, here they catch their small moving food - plankton - with their tentacles. Sometimes larger animals come across, the jellyfish pulls them into the stomach - and it is transparent, like its whole body, and, like flies stuck in amber, we see digested fish and crustaceans embedded in the dome of the jellyfish. To make it easier for them to float in water, jellyfish themselves consist almost entirely of water. But still, if they did not push themselves up, they would eventually sink to the bottom, contact with which would mean death, so tender are their jelly-like bodies. Farther from the bottom - closer to the light, closer to food - plankton inhabiting the upper 30-50 meters of the sea. This is the main law of jellyfish life.

In order to know where the bottom is and where the surface is, jellyfish have balance organs - statocysts - sacs with sensitive hairs in which grains of sand roll. The position of a grain of sand in the statocyst indicates the direction downwards, towards the bottom, which means you need to swim in reverse side. And the eyes, which distinguish the level of illumination, point the way upward - to light and food. Too bright light already scares away the jellyfish - it means that waves are very close, which can damage its soft body. The eyes and statocysts of jellyfish, together with the olfactory pit, are collected into single organs - rhopalia - there are many of them, and they are located along the edge of the jellyfish's dome. Strange as it may sound, jellyfish are not jellyfish all their lives, but two more animals that are completely different from either a jellyfish or each other. Not clear? Let's look at the life history of Aurelia.

Four white semicircles forming a wide cross in the umbrella of the aurelia, the testes of the males of these jellyfish. And in females, pink-violet ovaries are visible in the dome. Males fertilize the eggs, and they develop in the body of the females - look closely, in the photographs some aurelias show orange clusters under umbrellas. The eggs emerge covered with ciliaplanula larvae, they circle in the water, eating the smallest plankton. Having gained weight, planulae sink to the bottom and turn intopolypwith a mouth surrounded by tentacles. The aurelia polyp is tiny and difficult to find in the sea. New jellyfish bud from the upper part of the polyp and swim off to the sea - the wheel of Aurelia’s life has made a full turn.

AND aurelia, and cornerotbelong to the classscyphoid jellyfish- they are large. But in our sea there are several more specieshydroid jellyfish– you can’t see them without a microscope, and we will get to know them by studying the Black Sea plankton.

In other coelenterates - sea anemones, which we will meet on the stones, the polyp is large and strong - this is the main, long-lived stage of its life cycle. So who is the sea anemone - that polyp that looks like a luxurious blue or red flower that we find under the stones in the sea, or the planula larva circling in the water?
What is an aurelia: a saucer jellyfish, found everywhere along the shore, or a ciliated planula? Or is she a polyp with tentacles?
What is a crab - a bottom dweller in a powerful shell, a lover of dead shellfish, or a microscopic crustacean that catches single-celled algae in plankton?
From a biological point of view, this is the same organism, but its different entities - with different lifestyles and different habitats, occupying different ecological niches. What is the point of such complexity? Perhaps it is that, living differently at different stages of the life cycle, the organism depends differently on the environment. For example, there are many predators in the water column - planktonic larvae die, but the bottom stages of the life cycle survive. This is just one of the possible explanations - try to come up with your own.

Jellyfish immobilize or even kill their prey with the help of stinging cells, in which, rolled up with a tight spring, a capsule with poison and a sharp and jagged spear extending from it are hidden. The spring straightens, and the poisoned spear plunges into the body of the victim when it touches a sensitive hair on the surface of the stinging cell - a kind of trigger, or hammer of this weapon. In the body of the victim, the sharp tip of the hollow spear breaks off, and paralyzing poison pours out of it, like from a tube. The stinging cell is a disposable weapon: after firing once, it bursts and dies.

The batteries of poisoned harpoons are located in the Aurelia in the fringe of tentacles surrounding its umbrella, and in the Cornerot they are located on the beard of the mouth lobes hanging under the dome. It is interesting that shiny, big-headed mackerel fry are often packed in a whole flock between the mouth lobes of the cornet, traveling along with the jellyfish - and mysteriously they don’t care about the stinging cells. Just like clownfish live among the deadly tentacles of tropical sea anemones.
A small planktonic crustacean only needs one blow from a poisonous dart from a jellyfish or sea anemone to stop fluttering. Now imagine how many sensitive hairs you touch, how many times you pull the trigger when you touch a jellyfish in the water with your shoulder!

Ctenophores are living rainbows

It's magical beautiful creatures. They fill the waters of the Black Sea starting in April - transparent, weightless, and in sunny weather shimmering with all the colors of the rainbow. Not jellyfish, not even their relatives, they are not like anyone else. Separate type animal kingdom -ctenophores!

Watch them from boats, piers, coastal rocks, or even better - from under the water. They are openwork and light, like Chinese lanterns. Watch how they swim - they don’t flap their bladed skirts like jellyfish, but just... move. Along the body of the ctenophore there are sparkling cords - these are rows of rowing plates, they are so thin that the light passing through them is split into rays different colors– and each of the thousands of records plays with gemstone flashes. The cresting wave starts at the top of the animal’s head and runs to the other end of the body, the ctenophore swims - and it seems to us that a multi-colored electric discharge is sliding through it. Ctenophores are fascinating.

If you want to take a closer look at it, do not take the ctenophore with your hand, it is so tender that it will tear immediately; It’s better to scoop it out of the water with some kind of utensil or a boat made of your palms. But it is still best to look at ctenophores in their native environment - sometimes weak waves bring them to the shore unharmed.
The combing plates of a ctenophore are nothing more than microscopic cilia glued together in rows, side by side - the same as those of ciliates; this type of movement reveals them to be very primitive animals. Of the sensory organs, they only have an organ of balance, such as a statocyst, on the top of their head. There are ctenophores with lasso tentacles, which they throw into the water so that as much as possible of the small plankton on which they feed sticks to them.

This is the small one that has been living in the Black Sea for a long timepleurobrachiaand a large one that appeared here 20 years agomnemiopsis.

And there are ctenophores without tentacles, predators that eat other ctenophores - only ctenophores and no one else; These are floating stomachs, one side of the body of which is a mouth that opens to swallow the victim. There has been one such ctenophore in the Black Sea since the mid-1990s -beroe.
The appearance of Mnemiopsis in the Black Sea in the 1980s led to environmental disaster– it ate so much plankton and multiplied like that; detailed history the conquest of the Black Sea by Atlantic ctenophores, read the chapter on the properties of the Black Sea.
During the day they sparkle like underwater rainbows, and at night they glow! These are the largest luminous animals of the Black Sea, and while swimming summer night, you can get a little scared when a green flash suddenly flashes next to you, in the black water - you hit a ctenophore.
At night, underwater, flickering with a quiet green light, the comb jelly resembles a magic lamp; touch it with your finger and the fading light will flare up with renewed vigor.

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

Why do jellyfish swim to the shore?

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

Why are there so many jellyfish in the sea?

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

Jellyfish are among 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. These animals are 95% water, and 5% muscle fibers in their body make jellyfish a full-fledged organism.

In the sea you can find three types of jellyfish:

• Aurelia

She is also called " eared jellyfish" And all because there are transparent white tentacles along the entire circumference of the aurelia. This is the most small view jellyfish A peculiarity 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 of mouth cavities. The lace lobes are equipped with poisonous stinging cells. It is better to swim around such jellyfish.

• Mnemiopsis

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

Another book by biologist Lisa Ann Gershwin shocked American readers

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

My acquaintance with jellyfish is very superficial. It's just superficial. When they appeared on the surface of the water off the coast of the Black Sea on Cape Verde in Adjara, where our family usually spent their holidays, we boys caught them, threw them onto the hot stones of the beach and, enchanted, watched their gradual melting. Little did we know then that the day would come when jellyfish and people would change places, and jellyfish would watch homo sapiens die.

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

Now in America, as in Russia, it has become fashionable. They say that watching these hypnotic beautiful creatures promotes nervous relaxation of a person haunted by the rage of the day. Don't know. I haven't tried it. But I know that these beauties can sting stronger than any coquette. Some only slightly, others to death. In the north of Australia there are the most poisonous jellyfish on Earth. Their Latin name is Chironey fleckeri. The Americans dubbed them box jellyfish.

The bell of these jellyfish is one foot in diameter. But behind it stretches 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, you have two to three minutes to live. In Australia, 76 deaths from such touches have been recorded. There are many more unregistered people.

In 2000, this breed of jellyfish was almost destroyed Olympic Games in Sydney. Thousands of jellyfish flooded into the very places where the water competitions were supposed to be held. The organizers of the games were stumped. All proposals to get rid of jellyfish turned out to be unfeasible. But the Olympians were lucky. On the opening day of the games, the jellyfish disappeared as mysteriously as they appeared.

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

Such jellyfish, but smaller in size, are called irukandji. Their description was first 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 poisonous irukandji for thousands of years. Europeans had the honor of meeting them in 1964, when Dr. Jack Baris, in the best traditions of the Aesculapians, decided to test the effect of their bites on himself. (Residents of the coastal areas of Queensland suffered from them). The doctor miraculously survived.

Touching, even the lightest, the tentacles of these jellyfish causes the so-called. The affected area may be minimal in size and the person stung may not even feel anything. But after 20-30 minutes he begins to have strong contractions and aches. The pain is like being hit in the kidneys with a baseball bat. Then vomiting occurs, lasting all day. Spasms constrain the arms and legs, blood pressure increases greatly; it becomes difficult to breathe; the skin looks as if hundreds of worms have drilled through it. Victims ask doctors not for rescue, but for euthanasia. A person dies either from high blood pressure or from a heart attack. If he was in the water at that time, then he drowns. The threat from Irukandji is growing - from Cape Town to Florida.

But, so to speak, poisonous jellyfish that sting to death are just “flowers”, and it is not their poison that poses the main threat environment and to humanity. In his book, Doctor of Biology Gershwin writes that after 500 million years of “staying dormant,” jellyfish lived and went on a general offensive. Gershwin states: “What would you think if I showed you evidence that jellyfish have already displaced and replaced penguins in Antarctica? That jellyfish are capable of finishing off fishing, defeating tuna and swordfish? Starve out the whales themselves? Will you believe me? We know-nothings 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, networks full giant jellyfish weighing up to 450 pounds, capsized a Japanese trawler. His crew drowned. But even larger vessels fall prey to jellyfish.

On July 27, 2006, the modern American aircraft carrier Ronald Reagan docked in the port of Brisbane in Australia. The Australians, following the example of New Zealand, also decided to ban nuclear-powered ships from entering their ports. However, “Ronald Reagan” was driven out of Brisbane 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!” - screamed the headlines of Australian newspapers. Local fire brigades came to the aid of the ship’s crew, “just in case.” Residents of the city watched with bated breath the fight between the aircraft carrier and the jellyfish. But the fight turned out to be unequal. The aircraft carrier was forced to leave the port.

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

In December 1999, 40 million people in the Philippines suddenly lost power. 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 turned out to be jellyfish. They clogged the cooling system of the most important power plants and put them out of action. Rescuers scooped up a huge number of jellyfish, which required 500 giant trucks to remove.

Japanese jellyfish have been constantly attacked since 1960. nuclear power plants. Every day, an average of 150 million tons of jellyfish were removed from just one of them.

Gershwin writes: “Jellyfish have an amazing ability to attach themselves. Imagine a piece of thin plastic wrap in a swimming pool that can remain on the surface until the end of time without sinking. Until it clogs the water drain.” Chemical agents are powerless here, as are 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 are losing many millions of dollars when they are forced to close their wards.

Jellyfish can destroy entire ecosystems. Just such a catastrophe occurred when jellyfish belonging to the species 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 maintain the stability of the vessel on the water. By the 1980s, jellyfish had taken over the Black Sea, decimating fisheries in Georgia, Bulgaria and Romania, and hitting anchovies and sturgeon. 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 throughout the world. In fact, the entire Black Sea has, so to speak, become jellyfished. Scientists name four hypotheses that may have led to this disaster. The first hypothesis says that jellyfish defeated their rival anchovies by eating their eggs and plankton. The second hypothesis: the jellyfish, eating the anchovies' food, starved them to death. The third hypothesis: there were too many nutritious foods in the sea for jellyfish. And finally, the last hypothesis: climate change has led to the destruction of plankton and the proliferation of jellyfish.

The only salvation from the Mnemiopsis invasion is provoking " civil war"among jellyfish. Beros jellyfish, which have something like teeth, are released against Mnemiopsis. This helps them eat Mnemiopsis. So, only jellyfish are able to stop the invasion of jellyfish, and even then only partially. And then, beros horseradish is no sweeter than miemiopsis radish.

Jellyfish. And troubles follow. In 2000, Australians discovered jellyfish in the Gulf of Mexico. They were also brought in 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 the marine ecosystem. They ate ten times more than was typical in 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 struck the Gulf of Mexico - Hurricane Katrina and the 2010 oil spill. While other inhabitants of the sea began to die, the jellyfish not only did not die, but multiplied even more. By 2011, they had penetrated the Mediterranean. An average of 10 people fell ill from their “bites” per day. Many tourist beaches had to be closed at the height of the season. Meanwhile, jellyfish have reached the shores of Israel and Brazil.

The invasion of jellyfish has taken on a planetary character - from the Arctic to the Antarctic. What scientists say is happening is the “jellyfishing” of the oceans. Off the coast South Africa the huge number of jellyfish created something that was dubbed the “curtain of death” or “field of death.” It's about about a body of water of 30 thousand 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. Among other things, they block 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. Just listing the names of jellyfish speaks of their diversity. There are "moon jellyfish", "lion's mane jellyfish", "sea nuts", "aquavivas" and even "Portuguese warrior men". The last two types of jellyfish, strictly speaking, are not even living organisms. They are, rather, a collection of various jellyfish, which are called “personalities” in reverse. They function only collectively. Sometimes a bunch of them is amazing in size, sometimes 150 feet in length. As Gershwin writes, “these beings are neither individuals nor even colonies. For a century and a half now, the greatest minds in evolutionary biology have been debating what their true 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 for half a billion years, they are still able to survive in places where few other individuals can exist. They have a very low metabolic rate (normal) and therefore do not require much oxygen. They live quietly in waters where other ocean inhabitants would suffocate. Some jellyfish “inhale” 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 successes. Perhaps the fastest growing species is Mnemiopsis. Scientists call their reproduction “heromophroditic self-fertilization.” This means that such jellyfish do not need a partner and do not need a gender change. They possess both sexes. Jellyfish begin laying eggs as early as 13 days of age and are soon laying ten thousand eggs a day. Even if you cut these jellyfish into pieces, you will not be able to stop their reproduction. The quartered jellyfish regenerates and begins again " normal life" This “revival” occurs within two to three days.

Jellyfish are gluttons like Rabelais's Gargantua. Thus, Mnemiopsis eats food that weighs ten times its body, and increases in size every day. They manage this thanks to a truly fantastic metabolism. Jellyfish put more energy into their growth than the more complex creatures with which they compete. Mnemiopsis is not content with just satiation; it behaves like a fox in a henhouse - having had enough, it continues to kill its victims. Therefore, it makes no difference to the ecosystem whether jellyfish digest food or not. They continue to kill as long as there is anything left alive. And this happens with amazing speed. According to one study, Mnemiopsis kills up to 30 percent of the small crab population every day. “Jellyfish can eat anything. That’s what they do,” writes Gershwin. (Like the fabulous Robin-Bobin-Barabek). Some jellyfish do not even eat their victims, but absorb dissolved organic matter through photosynthesis.

Finally, the question of the death of jellyfish. Bringers of Death In fact, 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, the 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 water elements, where other creatures have appeared. So why are the jellyfish “breaking away” now? In the second part of his book, darkly entitled Jellyfish, the Planetary End and Other Trivia, Gershwin will try to answer this question and at the same time predict the future of the oceans, the Earth and humanity.

The author talks in detail about how other living creatures made great efforts to stop the onslaught of jellyfish. A critical 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 have become “unbelted.” A similar situation is observed off the coast of South Africa. Man has gone too far not only with fishing for anchovies, but also with fishing for almost the entire ocean fish world. The collapse of many ecosystems has given jellyfish a free hand.

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

And then there is the problem of oxygen in the water. This oxygen is created by algae using photosynthesis. High level oxygen contributes to the fight between fish and other waterfowl and jellyfish. But oxygen in water runs out faster than it is replenished. Therefore, when a person pollutes water bodies, for example, with enrichment waste from farms, he contributes to the creation of “entropic zones” with a lack of oxygen. This happens and naturally, and artificial, when people litter water bodies with waste, such as in the Baltic and Black Seas, or in the Gulf of Mexico. “Entropic zones” are spreading with alarming speed. No species that require even a moderate amount of oxygen are able to live in these zones, not fish, not crabs, no one, but jellyfish thrive there too!

Climate change is also good for jellyfish (lucky ones!). Warming ocean waters promotes the proliferation of tropical jellyfish. And jellyfish themselves are accelerating climate change. This happens in two ways. First, jellyfish release carbon-rich excrement and mucus. They turn them into carbon dioxide factories of sorts. Secondly, jellyfish absorb a huge amount of diverse plankton, which 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 begins to affect climate change.

And another misfortune is the acidification of ocean waters. This occurs 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 acidified than 30 years ago. Crustaceans suffer from this. This is how oysters disappeared from the American Northwest. Crustaceans have disappeared from the Arctic and Antarctic. Without having “shells,” jellyfish are better protected from acids, and the crisis of oxidation of ocean waters does not bother them.

Dr. Gershwin writes that jellyfish are taking over the oceans "one step at a time." She believes that this is an irreversible process. Arises new balance forces in which jellyfish will dominate. “We are creating a world,” says the author, “more like the Precambrian era than the late 1800s, a world in which jellyfish dominated and organisms with shells did not yet exist. We are creating a world in which people will soon not be able to exist, and they are unlikely to want to.”

Is there a way out of this terrible dying? Yes, Gershwin answers. We must eat those who eat us. According to ancient Chinese texts, jellyfish have been on the human menu for 1,700 years. Currently, the global jellyfish harvest is 321 thousand tons. Their main consumers are China and Japan. If we do not develop an Asian appetite, we are doomed to destruction, the author argues.

The United States has already realized the threat of jellyfish. Back in 1966, Congress passed a law to control jellyfish. It was updated in 1970 and 1972. The law requires the Secretary of Commerce to conduct research to determine the number of jellyfish and their impact on fish. True, the funding for this law is ridiculously meager - only $1 million. Much larger sums are spent on the destruction of humanity.

This is what the final chord of Gersha’s book sounds like:

“When I started working on this book, I still had the feeling that the problem was solvable. But I apparently underestimated how terrible the damage we have done to our oceans and their inhabitants. Now it seems to me that we have gone too far and have passed the point of irreversibility, not knowing where and when this irreversibility began. These will be oceans without coral reefs, without mighty whales, without staggering penguins, without lobsters and oysters. And with sushi, but without fish. So adapt!” After the gourmets, our turn will come, the turn of ordinary homo sapiens. And my imagination imagines the shore of the Black Sea on the Adjarian Cape Verde. But it’s no longer us, boys, catching jellyfish and throwing them onto the hot stones and sand of the beach and, enchanted, looking 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

The sea wasp (box jellyfish) belongs to the class of box jellyfish. This is multicellular - rare and very dangerous for humans. In nature, there are a huge number of different ones, but this is considered the most poisonous on the planet. It stings just like the well-known wasp, only instead of one sting, the box jellyfish has a hundred times more. Their poison is death for all living organisms. Over the past century, these predators have killed about a hundred people. If a diver gets caught in a school of sea wasps, he has virtually no chance of returning to shore.

What is called a sea wasp?

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

You cannot call this creature a monster when you see it. These are relatively small jellyfish, shaped like a cube or bottle. The body is about 5 cm in diameter, although there are rare individuals, whose dome reaches 20-25 cm. It is better not to meet with such people, as they are 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 weapons of the jellyfish. They reach a length of 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, scary lashes, so they produce poison that is stronger than that of a snake.

Scientists cannot figure out another feature of the sea wasp - why does a jellyfish, which has no brain, need eyes, can it see? the world around us? Surprisingly, the box jellyfish actually has eyes - twenty-four. These organs are divided into 4 groups of 6 eyes each. With such numbers, should this creature be able to see?

Where do sea wasps live in nature?

It would seem that a jellyfish can live in any sea ​​water. All water expanses of the oceans and seas are subject to these tentacled miracles, but this is an incorrect statement. The sea wasp, for example, lives only in Australia. Favorite place sea ​​predators- the 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 remains completely motionless, 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 affects 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 inside, where it calmly digests it.

Box jellyfish hunt in coastal zone, but stay far from the shore. During a storm or high tide, when the sea is rough and strong waves roll ashore, these poisonous creatures often end up directly on the beaches where people swim.

Reproduction

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

After a certain time, the jellyfish’s body breaks away from the polyp and swims away to do its dirty 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 it such a bloodthirsty predator, it only attacks what can serve as food. People are not included in this list; when meeting them, the sea wasp prefers to swim away. It can sting a person, but only by accident, when it does not have time to dodge the collision. Divers are most often exposed to this danger.

After receiving several doses the strongest poison, the body instantly begins to react. The skin turns red, the stung person feels unbearable pain from which there is no escape, the burn site swells terribly. Dizziness, fainting, high fever - these consequences of an encounter with a sea wasp may well result in respiratory arrest and cardiac arrest. Death can occur in the very first minutes after a collision with the deadly tentacles, or it can occur within 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, and moves relatively quickly underwater - up to 6 meters per minute. It is possible to see transparent predators only in shallow water; the warm sandy bottom is best place for their existence and reproduction. During the daytime, sea wasps remain at the bottom and emerge to the surface at the first twilight.

To protect beachgoers from jellyfish, rescuers place warning signs along the shore, but unfortunately, this does not guarantee people complete safety in places where sea wasps, the most poisonous among jellyfish, are found.

We have already written that on . Now the waves are throwing dead animal carcasses onto the shore in huge quantities.

Experts associate the invasion of jellyfish with changing temperatures and ask Odessa residents to be careful. However, due to the colder weather, city residents do not go into the water, but simply watch sea ​​creatures from the outside. Many of them organize a kind of flash mob on social networks, where they post photographs of jellyfish of different colors and sizes.

“I often ride a bicycle to the Seaport,” said young Odessa resident Nastya. lately I noticed a large number of jellyfish. From the outside they look terrifying and fascinating at the same time."

beautiful, strange creatures called cornorots (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. Clusters of them can also be found off the coast of South Africa, where the cold Bengal Current passes.

This type of jellyfish can cause burns to humans. Touching the tentacles causes a sensation similar to a nettle sting. Jellyfish mucus is also toxic. After touching the jellyfish with your hands, you should never touch your eyes, lips or nose. The burn site must be immediately washed with water, preferably fresh water.