Who are they - the inhabitants of the Bermuda Triangle in the mysterious Sargasso Sea? The very heart of the giant whirlpool in the middle of the Atlantic is teeming with bizarre organisms, wandering eels, and…plastic debris.
text: Lars Abromeit
Everything is shaking. The steering wheel strives to escape from the hands. The sheets creak, the storm wind howls in the shrouds.
We went to sea on the training sailboat Corvit Kramer three days ago. A day later, the land disappeared from sight. To the very horizon - continuous waves of the Atlantic in foam "caps". Nothing to catch the eye. And there are still eleven days of sailing ahead. Our 41-meter brigantine, which the team affectionately calls "Mother Kramer", despite all the satellite navigators, emergency beacons and life rafts, seems like a helpless tiny sliver.
We are all alone 220 kilometers north of Puerto Rico, right in the middle of an amazing giant whirlpool in the Sargasso Sea. If someone gets sick, if a sail breaks, or if there is a fire, you can only rely on yourself.
The Sargasso Sea has no shores. Its boundaries are not beaches or rocky reefs, but ocean currents. In the west - the Antilles, in the north - the warm Gulf Stream, in the east - the cold Canary Current. It carries water from the depths off the northwestern coast of Africa and south of the Sargasso Sea passes into the North Equatorial Current. Together, these ocean currents twist into a huge spiral that rotates clockwise around Bermuda - the only piece of land within a radius of more than a thousand kilometers. Marine organisms carried by the currents can get stuck in this gigantic whirlpool for years, or even decades.
In the center of the spiral, there is a complete calm for weeks, due to which sailors from sailing ships nicknamed this accursed place "a trap for lost souls." Christopher Columbus was the first to hit it in 1492 during his legendary voyage in search of a western route to India. The languid calm got on his nerves. His companions feared that they were no longer destined to return to Spain.
The famous navigator was the first to describe the unique golden clusters of floating algae with green air bubbles at the ends of the branches. The Portuguese sailors who accompanied him called them "sargasso" - in honor of the small grape variety. It seemed to Columbus that they were in an enchanted place. Dense carpets of algae, birds, a strip of fog and whales clearly indicated the proximity of land. But there was no land. The compass needles danced like crazy, and at night the crew was frightened by a strange glow in the ocean.
Since then, there have been many legends about the Sargasso Sea and the Bermuda Triangle in its western part - with creepy ghost ships, floating islands and "space channels" through which extraterrestrial forces drag ships and planes into another dimension. This area of the Atlantic between 45 and 75 degrees west really holds many secrets. Even for scientists. It is believed that sea turtles have been drifting in circles for years in the tangles of the Sargasso. A bizarre moonfish spawns here, and larvae and juveniles of swordfish, golden mackerel and marlin are unusually common. As well as dozens of species of whales. River eels swim thousands of kilometers from North America and Europe to find a mate in the Sargasso Sea and produce offspring.
Who else lives here? Has our civilization reached these distances? And if so, how did it affect the local ecosystem?
The members of the expedition organized by the Woods Hole Oceanographic Institute (Massachusetts, USA) are trying to answer these questions. Goal of a team of 37 specialists: to sail from the eastern border caribbean more than one thousand miles towards Bermuda - and further to New York to study the flora and fauna of the high seas.
In addition, the expedition also has an educational mission. Professor of Oceanography Amy Siuda of the Association for Maritime Education at Woods Hole (USA) took fourteen students with her.
Their task is to study the accumulations of Sargasso with their inhabitants floating on the surface of the sea, as well as particles of garbage.
Ambitious project. Firstly, the area that the expedition members are going to comb in the open sea is comparable in size to the territory of the European Union. Secondly, the Sargasso Sea is fraught with many dangers. There are huge depths here - under the keel of our sailboat, the highest peaks of the Alps would now easily fit. And unpredictable weather, which at one time almost drove Columbus to despair.
But our "Admiral" Amy Siuda is not afraid of the vagaries of the Sargasso Sea. She has been throwing her "net" into it for 17 years.
The guys from the “A” team, after a night watch, fall exhausted into their beds. Ten o'clock in the morning. Among the waves, the first bunches of sargasso are already flashing. It's time for us to work.
Amy Siuda on recent months pregnancy. But this does not prevent her from commanding her students. With the help of a winch, they lower three nets overboard, with which they will trawl the sea: one at a depth of 70 meters, the other at 150 meters, and the third at the very surface. Where the Sargasso drift.
The researchers are bringing dozens of beams aboard. Each of them is a miniature forest in which life is seething. Branches of algae are covered with tiny cnidarians and barnacles. Drifting across the sea in their houseboats, they feed on plankton. Poisonous slugs swarm among the air bubbles on the stems. Their golden coloration is the perfect camouflage. Predatory shrimp smaller than a fingernail search for prey in dense thickets. In one of the bunches, even a Sargasso sea clown hid, tightly clinging to the branches with its pectoral fins. He changes color like a chameleon, explains Siuda. And he hunts from ambush for small fish or his relatives.
More than 140 species of invertebrates and 127 species of fish find food and shelter in the Sargasso. Ten of them, including anglerfish, needlefish, crustaceans, snails and sea anemones, spend their whole lives in them. Others look into the Sargasso in passing. For example, flying fish, twisting "nests" of bubble caviar under their canopy. Large migratory species such as tuna or sailfish come here to hunt. And it is here, as we managed to find out with the help of radio beacons, that sea turtles spend the first years of their lives. Seaweed carpets serve them reliable protection. In addition, the water in the Sargasso is several degrees warmer than in the open sea, which contributes to the growth of reptiles. Birds also visit the floating islands - typhoons, terns and boobies feed and rest in the Sargasso Sea during transatlantic flights.
In the ecosystem of the open sea, sargasso act as "mini-incubators". But about the algae themselves, which about 40 million years ago separated themselves from their coastal relatives and went into free swimming, surprisingly little is known.
There are two types of them: floating sargassum and submerged sargassum. The first has smaller leaf plates, the second has larger ones. But do they differ from each other in the species composition of their inhabitants? And on what routes do they drift across the sea?
“The only reliable source of information about these algae is from the Marine Education Association expeditions,” says Siuda. “For the past 20 years, they have been the only ones who have been making regular observations in the Sargasso Sea.” The conclusion of the participants of these expeditions is unequivocal: two species of Sargassum algae form the same different ecosystems as coniferous and deciduous forests. And they are inhabited by different organisms. Swimming Sargassums seem to have been drifting with the current for years all the way to the straits of the Caribbean Sea. And the submerged slowly move within the southern part of the Sargasso Sea. But why?
"It's hard to say," Siuda replies, unraveling the tangles of seaweed. Scientific data is still insufficient, and it is extremely difficult to collect them.
First hour of the night. The port of St. George in Bermuda is about 500 nautical miles away. The excitement finally stopped. On the sea, only a slight swell.
In the laboratory cabin, plankton researchers evaluate the evening's catch. Siuda is distributing the captured eel larvae to the students, who are to take tissue samples for DNA analysis. Under the microscope, leptocephalic larvae look like ghosts: a completely transparent flattened body, a tiny head with a mouth bristling with sharp teeth. They have so little in common with adult eels that for a long time scientists considered them a separate species.
Our team already has about 300 larvae. Most belong to the conger family - these are conger eels. But there are also several larvae of the river eel among them. For explorers, these are real treasures. Perhaps they will provide clues to one of the biggest mysteries of marine biology: where exactly do European eels come from?
Disputes about this have been going on since antiquity. Fish similar to snakes are born from bottom silt, Aristotle believed. No, they multiply by rubbing against rocks, Pliny the Elder assured. Eels hatch from drops of morning dew, Isaac Walton, author of The Artful Angler, argued authoritatively in the 17th century.
Today, all evidence points to American and European river eels swimming to the Sargasso Sea, where they mate, spawn, and then die. In any case, it was here, south of Bermuda, that the youngest eel larvae were found. But decisive evidence is lacking. They could be eel caviar. Or a photo of a mating pair. Or at least the corpse of an adult eel from the depths of the sea. Any such find would be a sensation.
But for now, biologists have to be content with hypotheses. Presumably, during migration, eels are guided by ocean fronts - the boundaries between two water masses with different temperature, chemical, or dynamic characteristics. And perhaps by magnetic field earth. So they swim more than 6,000 kilometers - from the coast of Europe across the Atlantic. At some point, they find their "half". And their larvae drift along the Gulf Stream back to Europe.
But why such difficulties? So far there is no answer to this question. It is possible that this is just an atavism. Eels may have spawned in the Sargasso Sea region 130 million years ago when the continents were closer friend to friend. Or maybe it's all about the abundance of algae. Flat larvae have plenty of nutritious “sea snow” here - particles of dead algae that stick together with the secretions of planktonic organisms and rise to the surface with air bubbles at night.
All these are just hypotheses, but the example of the eel shows how complex the ecosystem of the open sea is organized. It is permeated with a whole network of migration routes, along which even fragile eel larvae can get alive and healthy from the Sargasso Sea to the rivers of Europe.
Ocean routes depend on natural elements. The Gulf Stream alone pumps every second 150 times more water than all the rivers of the earth combined. Short-term water eddies push cold masses of water saturated with nutrients from the depths to the surface. And in the middle of the Sargasso Sea, blooming oases suddenly appear, where there are almost 100 thousand times more planktonic diatoms than in neighboring water areas. This oceanic "desert" produces every year three times more plant biomass than its equal size Bering Sea, which is considered very "fertile".
But sea currents are not very picky. Along with sargassum, plankton and eel larvae, they carry garbage from our cities into the open sea. Millions of tons of garbage enter the seas every year (see infographic on page 40). Only a small part of it is visible from the Corvit Cramer: plastic bottles, pieces of foam. But on the net it comes across in frightening quantities: up to 200 plastic fragments in half an hour.
Basically it is the so-called "microplastic". Multi-colored particles smaller than five millimeters make up 90 percent of the plastic debris drifting across the oceans.
The spread of microplastics in the oceans is one of the most serious environmental issues modernity, experts say. Microparticles, like magnets, attract and accumulate toxins, carcinogenic chloride compounds and heavy metals. Then they are absorbed by the smallest filter feeders: copepods, planktonic larvae, salps, molluscs and fish fry. And finally, passing through food chain back to people again.
In addition, microplastics carry disease-causing viruses and bacteria through the oceans. What exactly? This is what Siuda is trying to establish together with microbiologist Will Mellvin. Back in 2013, their colleagues were able to prove that more than a thousand species of bacteria live on individual microplastic particles in the Sargasso Sea. Some of these nomadic communities are dominated by bacteria of the genus, a group of microbes that includes cholera pathogens and deadly nerve poison generators. Thus, under the cover of the sea, a completely new ecosystem is formed. Siuda calls it the "plasticosphere".
On the fourteenth day of sailing, a land finally appears on the horizon: Bermuda. But a nine-point storm that has flown in from the north makes us “dance” on the waves for another thirty hours, writhing in bouts of seasickness.
Flaming sunrises, the roar of a storm, endless expanses - the sea does not skimp on grandiose spectacles. But at the end of the voyage, only one prosaic detail remains in the memory: two hundred plastic particles in a small test tube with sea water.
Will the day come when there will be as many garbage patches in the Sargasso Sea as islands of algae? Who will prevent this ecological apocalypse? The Sargasso Sea is outside state borders, and it is very difficult to protect it based on international law. Moreover, even the status of the sea protected area still will not protect it from plastic debris: it is known that sea currents can carry a piece of plastic across the Atlantic in just a few weeks.
In 2010, American scientists tried to assess the possible damage from the "plasticosphere". As they moved east from Bermuda, they recorded up to 26 million microplastic particles per square kilometer - about the same as the concentration of plankton. Scientists have suggested that after a couple of miles this figure may increase.
But they failed to verify their guess: they had too little time, and the sea turned out to be too large.
Sargasso Sea- one of the most unknown, mysterious, dramatic but at the same time beautiful seas in the world. And all thanks to the fact that it is literally carpeted with algae.
Mysterious Sargasso Sea
Small larvae hatch from the eggs. They swim to the upper layers of the water, where they are picked up by the Gulf Stream and carried to the northeast. So they swim from two to three years to Europe. Getting to the shores of the mainland, they grow up and become like large eels, only while they remain transparent. A few months in fresh water turns them into the fish we know them to be. After that all life cycle repeats again.
Many more questions remain unanswered. For example, how eels navigate in water, why they need to swim so far to spawn, how larvae find their way to their native rivers, why females live in the fresh water of rivers and lakes, while males remain in the mouths and do not rise high.
Sailors and pilots cannot find an answer to the question of where ships and planes disappear without a trace in bermuda triangle. In many cases, radio communication with ships is suddenly interrupted. Some of these warships were equipped with last word technology. Planes disappeared from radar screens. Subsequent searches turned up no results.
If zoologists can soon find out the secret of eels, then the Bermuda Triangle will excite people for a long time to come. Many hypotheses and sensational discoveries will be due to this mysterious corner of the Sargasso Sea.
If you visit those places, you can also touch these ancient secrets of our planet.
Have a good trip, and most importantly - a safe return)))))
On September 16, 1492, when the sun rose over the ocean, the sailors of the X. Columbus squadron saw an unknown sight around them. The whole sea up to the horizon was covered with algae. Brown, tangled lumps floated now singly, now in whole fields. Eight days had passed since the caravels left the Canary Islands astern and turned west. X. Columbus triumphed. This means that the longed-for India is very close: accumulations of algae are a sure sign of the proximity of the earth. But a share of bewilderment was mixed with joy - too quickly the squadron reached the goal of its journey, this did not fit with any calculations. However, it wasn't worth it to grieve. The weather was excellent, a warm breeze filled the sails, the algae gently swayed on a gentle wave, the lot did not reach the bottom: the voyage was not only safe, but also pleasant.
A day passed, then another, a week ended, and the stems of three small sailboats continued to push apart the greenish-brown rafts and ridges of strange plants. The ground was still invisible. October came, the number of algae increased every day, from the low side it was visible how some living creatures swarm inside the algal lumps, small brown crabs swim on the surface of the genera, bizarre fish with shaggy, algae-like fins hide under the lumps of plants. There was no shore. The days dragged on. And suddenly it was all over. The algae disappeared somewhere, the wind changed direction, the squadron was moving along clean water. In the early morning of October 12, the long-awaited cry was heard: "Earth!" According to a pre-given order, the squadron saluted with a volley of guns. America was open. True, none of the team knew about this, Columbus himself did not suspect about his discovery, because until the end of his days he imagined that he had found only a new way to India. He also did not know that he had discovered and crossed the only sea on the planet without coasts.
This unique sea owes its existence to currents and wind. Off the coast of Africa in the region of the Cape Verde Islands, a warm current originates, which is directed along big circle towards America. It crosses the Atlantic Ocean a little north of the equator and bifurcates, bumping into the Antilles. Part of the waters of this equatorial current turns along the ridge of islands to the northwest, its jets merge with warm waters Gulf Stream, and near the Azores turn south, thus closing a wide ring. All floating objects, from chips to ships abandoned by the crew, once in this giant whirlpool, cannot go beyond its limits, which is clearly indicated by the paths of the remains of the ships, traced from the ships sent to tow or destroy them. The French geographer Camille Vallot reports that the schooner Fanny Walter traveled 14,000 kilometers in three years before sinking to the bottom. The ship "Fred Taylor", having described an exact circle across the ocean, broke into two parts at the border of warm and cold waters. Of the 230 ships abandoned by the crew between 1900 and 1907, none were swept outside the circle. Floating algae do not leave it either.
Columbus named the body of water he crossed the Grass Sea. Its modern name - Sargasso Sea - comes from the Portuguese word "sargasso" - a variety of small grapes. Brown algae with many spherical floats, apparently, reminded Portuguese sailors of grapes. Two species of these brown algae - floating sargassum and submerged sargassum - constantly drift on the surface of the sea that bears the same name. Plants of both species are devoid of attachment organs and represent a tangled mass. The wind drives individual clumps of algae into rafts and ridges, stretching one parallel to the other for many kilometers. Sometimes sargassums accumulate in such huge numbers that they form a solid brown carpet, giving the ocean the appearance of a flooded bottomless swamp.
Sea currents do not have a strictly defined channel, they can deviate from the main direction either to the right or to the left. A sea without shores is constantly changing its shape, but only within certain limits. On average, it is located between 25 and 35 degrees north latitude and 40-75 degrees west longitude.
The basis of life in the Sargasso Sea is algae. They serve as a place of attachment for sessile marine organisms, herbivorous animals feed on them, fish and crustaceans, mollusks and worms find shelter in sargassums. Both types of sargassum cannot grow by attaching to the bottom, so animals of the sargassum biocenosis are not found anywhere outside their ever-swaying world.
Here they are born, grow, multiply and die. Over a long path of evolutionary development, all members of the Sargassum biocenosis adapted to each other, adapted to unusual living conditions in the ever-drifting thickets at the border of water and air. And the plants and animals of the Sargasso Sea cannot drown: they are all equipped with swim bladders, various cavities filled with gas. Mobile animals have tenacious paws or suckers with which they are held on algae. Non-motile organisms adhere to algae.
In animals of the Sargassum biocenosis, you will not find bright colors: they all wear a protective khaki uniform, often camouflaged in several tones. Lacy calcareous white colonies of bryozoans from the genus membranipore are attached to the algae. Accordingly, large Sargasso animals usually bear whitish spots. You have to peer into a lump of sargassum for a long time before you see a lurking crab or fish in it, so completely their color and shape merge with the background.
To get a closer look at the life of the Sargasso Sea, it is best to scoop up a large ball of algae with a net and place it in a wide basin with a bright bottom. Everything that was in the lump itself or in its vicinity will certainly end up in the basin. Even animals as mobile as fish, crabs or shrimps never try to get away from the net. On the contrary, at the slightest danger, they only get deeper into the algae and never want to part with it. Even those lumps of sargassum that are picked up from the water not with a net, but with a hook or an iron cat, get on board along with their population.
The Sargassum biocenosis includes about 60 species of various plants and animals. On the two main types of brown algae, the beaded red algae ceramium settles, forming small branched bushes. Some other types of small algae (red and green) also grow here.
Colonies of delicate hydroid polyps can only be seen with a magnifying glass. They feed on the smallest planktonic organisms, mainly the larvae of various animals of the biocenosis: the plankton of the Sargasso Sea is very poor in the spaces between the clumps of algae. The hydroids themselves serve as food for several species of small sea spiders and nudibranchs. The latter, like most members of the biocenosis, are brown-yellow or brown-green in color with whitish spots.
Of the nudibranch molluscs, a small scyllea, equipped with shaggy outgrowths, imitating the tips of the “leaves” of sargassum, attracts attention.
Among the algae, in search of food, small nautilograpsus crabs make their way, which, like the sargasso shrimp, are brown in color.
Large crabs of the genus Portunus swim boldly from one aggregation of Sargassum to another. They quickly overcome the open space of water and deftly hide in saving thickets.
This is where they hide special types seahorses and sea needles. The needle-fish of the Sargasso Sea imitates the "stems" of algae with such accuracy that it can not be found even in an aquarium, although it is known that it is there. The large Sargasso clown fish, or Antenarius, has a striking appearance. The body of the clown fish is covered with many branched outgrowths resembling the tips of the sargassum. The fins of this fish are also ragged. Antennarius always keeps under the algae ball, into which he climbs at the slightest alarm. It is extremely interesting to watch this fish in an aquarium. While a bunch of sargassum floats on the surface of the water, the clownfish is almost motionless, it only slowly moves its fins along with the swaying tips of the algae. As soon as the sargassum is taken out of the vessel, the clown fish loses his temper. She rushes from wall to wall in search of shelter and does not calm down until the sargassum is put in place. The clownfish also breeds its offspring among the algae. She glues the “twigs” together, and as a result, a small nest is obtained, where the eggs are deposited.
The origin of the Sargassum biocenosis has not yet been fully elucidated. The initial assumption that the floating Sargassums were pieces of coastal seaweed turned out to be incorrect. Off the coast of Africa, off the Antilles and on the coast of America, these species are absent. Yes, they cannot grow at the bottom, as they are deprived of attachment organs. The adaptation of these plants to life on the high seas could develop only over a long time - it indicates the long-term constancy of environmental conditions in the Sargasso Sea area. The population of the Sargasso originated, apparently, from accidentally introduced coastal littoral organisms. The peculiarity of conditions and long-term isolation contributed to the formation of new species that inhabit the world's only sea without coasts.
As a rule, the status of the sea receives a small space in the ocean, which is framed by islands and shores of the continents. However, the Sargasso Sea is an exception, as it has no shores at all. Such a kind of "sea without shores" stretches in the west of the Atlantic Ocean. Unlike other seas, the Sargasso Sea is different unique properties water, amazing calmness and features of the living population, you will not find this in the waters of the Atlantic. Such differences are facilitated by the circulation of currents, which goes clockwise, creating peculiar boundaries in the sea.
To date, the Sargasso Sea remains mysterious place for humanity. In the Middle Ages, there was an unkind rumor about him. And the reason is that a significant part of the maritime territory is located in the Bermuda Triangle, which is located in the southwest of the Atlantic Sea. In addition, the Sargasso Sea is considered the only sea of its kind that has no boundaries on land. From all borders, the Sargasso Sea is beaten off by strong currents, among which is the Gulf Stream. Also in this zone of the World Ocean there are strong thickets of algae, which, floating on the surface of the sea, resemble land islands. Such islands sometimes circle in place, but it seems that sea water here it is motionless, because they move very slowly.
Another mystery of the Sargasso Sea is the year-round calm, windless weather. Therefore, this sea has a bad reputation, it is called a graveyard of ships. Medieval sailboats, falling into a calm, stopped, and rowing by hand was not possible due to algae. For this reason, the sailors relied on the appearance of the wind or slowly died.
Interestingly, only algae grow in the Sargasso Sea, but their quantity is sufficient for most small fish and other living creatures that live and feed among them. Many fish choose these waters for breeding because of the warmth, salinity and cleanliness.
Inhabitants of the Sargasso Sea
It is the Sargasso Sea that is called the birthplace of eels that live in the Atlantic Sea basin. Eels swim here to spawn, from here they do not return back. Eel larvae hatch in local waters, and then fry develop. Adults are sent to Europe.
Science fiction writers appreciated this interesting natural object. Edward Hamilton, Jules Verne, Warner Munn, André Norton and many others often used Sargassum seaweed or the Sargasso Sea theme in their works.
It is noteworthy that almost all living creatures of the Sargasso society are distinguished by their color and shape, which is hidden in algae. The fish resemble twigs and leaves, and the body color has yellow-brown hues that perfectly mask them. It is difficult to see a seahorse among the Sargassum branches. The sargasso sea clown is also disguised - its body resembles a sargassum branch.
Most people are familiar with the breeding history of the European eel in the Sargasso Sea. After all, for hundreds of years no one knew exactly where this fish breeds. This has been the secret of the Sargasso Sea for centuries. Interestingly, they create offspring in its waters, then return here to die in its depths. Such loyalty to the motherland is an amazing development among the fish community.
A little more about the inhabitants
It is noteworthy that it was thanks to the eels that scientists were able to detect the current at a considerable depth of the ocean, because the fish goes here. The discovered current is the opposite of the Gulf Stream, which is why it received the name Anti-Golf Stream. Thanks to this current, the eels return to their spawning grounds. The story of eels is endless, the American eel from North America spawns in another region of this sea, and uses a certain branch of the current as a passing transport to rivers and American shores.
The inhabitants of the Sargasso Sea are sea turtles that rescued sailors during the calm. These wonderful turtles feed on algae. Jellyfish and invertebrates are also found here. Even sharks are found in this unusual sea, mainly: pelagic sharks, blue sharks, silk and mako. Almost no one swims in this sea, so sharks do not pose a danger to people.
