Giant stingray. Monkfish (anglerfish)

Giant freshwater stingray June 17th, 2013

We all know about the manta ray or the largest ray in the world, whose body width can reach 7 meters. But few people have heard about its giant freshwater brothers. They can grow up to 4.6 meters in length and up to 2 meters in width - Giant Freshwater Stingray (Himantura Chaophraya)

The very existence of the giant freshwater stingray is shrouded in mystery. No one still knows exactly how many stingrays live in the tropical rivers of Malaysia, New Guinea, Indonesia and Thailand, in what conditions they live most comfortably, and whether they happen to go out into the open sea, where their closest relatives live.

The habitat of these stingrays are the rivers of Thailand (Mekong, Meklong, Chao Phraya, Tachin, Ban Pakong, Tapi), Indonesia - the Mahakam River basin on the island. Kalimantan, Malaysia - Kinabatangan River in Sabah. They can also be found on the island of Borneo, New Guinea and Australia.

These ancient representatives of the class cartilaginous fish have remained almost unchanged during their existence. Just like millions of years ago, their brownish-gray body retains a round shape like a huge saucer, a long whip-like tail and a pair of small eyes. They still burrow into the sandy or muddy bottoms of tropical rivers, breathing through holes in their upper bodies. Here they lie in wait for their prey, crabs or shellfish, recognizing their approach by the electrical signals they emit.

The freshwater stingray's body is disc-shaped with a small triangular snout and a long flexible tail. Sometimes the diameter of the disk can reach 2 meters. The weight of this giant is about 450-500 kilograms. The upper side of the stingray is brown in color, and the lower side is white with small gray or brown streaks on the sides. The skin on the “back” feels like sandpaper to the touch.

In the front of the body there are small eyes, gill covers and a mouth armed with many teeth. On the skin around the nose and mouth on the underside there is a kind of touch sensor that allows you to detect magnetic and electric fields other living beings. This device makes it easier to find food. With the help of a sensor, a stingray can easily detect prey hidden at the bottom of the river or hiding in the dark and muddy water.

The freshwater stingray has in its arsenal terrible weapon– 2 powerful and sharp spikes located on the tail. Each of them has its own purpose. A large internal spine is used to hold the victim. It works on the principle of a harpoon, i.e. The thorn penetrates the victim’s flesh like clockwork, but many jagged edges prevent it from being pulled out. The blow of this stingray's tail is so strong that it can pierce big thorn even the bottom of the boat. Therefore, no rubber boots or wetsuit will save a diver from his weapon. The length of this spike can reach 38 centimeters.

The stingray swings its tail very skillfully and almost always hits the target. To be fair, it should be said that the stingray does not attack just like that. To do this, he needs to be quite disturbed or grabbed.

The second spike is smaller. Its main purpose is to inject poison, which is very dangerous for humans and can lead to death. The poison looks like thick, dark mucus. It passes through a special groove leading from the poisonous glands.

The stingray's diet consists of fish, shellfish, crustaceans and other aquatic invertebrates.

As for the reproduction of these fish, these stingrays are viviparous. The female gives birth to one calf, about 34-35 centimeters long.

And although stingrays do not attack people without reason, ordinary contact with them is not always safe. At the base of the river giant’s tail there is a long (up to forty centimeters) poisonous thorn, easily piercing not only the skin, but also the bones of a person. There are cases when a giant freshwater stingray overturned the boats of its overly persistent pursuers.

A female stingray of unprecedented size was caught in Thailand. In order to drag sea dweller into the boat, it took the efforts of 13 adult men.

A giant stingray was caught in the waters of the Maeklong River. For almost an hour and a half, the fishermen struggled with him, lifting him on board. When they managed to drag the monster into the boat, the researchers were delighted: they were lucky enough to get the largest specimen in history. Its weight was 350 kg, and its dimensions were two by two meters, not counting its three-meter tail.
The giant turned out to be a female, and a pregnant one at that. The lady was treated with care. Specialists working within the framework of the International Union for Conservation of Nature program, which provides for the conservation of endangered fish species, placed it in a pool, where they took DNA samples. After a painless procedure, the mother was released back into the river.

By the way
Giant stingrays are dangerous. From such poison sea monster World famous Australian explorer dies wildlife Steve Irwin. This happened in 2006 off the coast of Australia in the Coral Sea in the Great Barrier Reef area.

Sexual dimorphism at its finest. Shows it off devil fish. Male and female specimens of this deep-sea creature, as if from different worlds. Females reach 2 meters in length and have a lantern-like growth on their head.

Fish sea Devil

It shines in the water column, attracting prey. Male devils are 4 cm long and lack a lighting device. This is not the only interesting fact about deep sea creation.

Description and features of devil fish

Devil fish in the photo seems awkward. Many are repulsed by the appearance of the animal, for which he was compared to the devil. Devil fish are distinguished from standard fish by:

Flattened body. It was as if someone had stepped on him from above.
Big head. It accounts for 2 thirds of the animal.
A sort of triangular body, sharply tapering towards the tail.
Almost invisible gill slits.
Wide mouth, opening over the entire circumference of the head. The upper jaw is more mobile than the lower jaw. The latter is pushed forward. The fish seems to have a snack.
Sharp and curved teeth inside the mouth.
Flexibility and mobility of the jaw bones. They move apart like snakes, making it possible to swallow prey larger than the hunter himself.
Small, round and close-set eyes. They are brought down to the bridge of the nose, like a flounder.
Two-part dorsal fin. Its back part is located at the tail and is soft. The anterior area of the fin is equipped with 6 hard spine-ribs. Three of them go to the head. The anterior ray is shifted towards the jaw and has a thickening. It is called an esca and serves as a home for glowing bacteria.
Presence of skeletal bones in pectoral fins. This partially gives them the function of legs. Devils move on their fins along the bottom, crawling or jumping in a peculiar way. Swimming ability monkfish are also not deprived. The fins also help bury themselves in the ground, hiding from prying eyes.

Caspian sea devil

Eating devil fish

All sea devils are predators. As an exception, fish rise to the surface of the water, hunting for herring and mackerel. Sometimes sea devils grab birds rocking on the waves. But usually bottom predators hunt at the bottom, catching there:

bearded devil

squids and other cephalopods
gerbils
stingrays
cod
flounder
blackheads
small sharks
crustaceans

Devils wait for fish victims, hiding at the bottom. The light of the predator’s “lantern” attracts the inhabitants of the depths. When potential victims touch the esku, the devil suddenly opens his mouth. A vacuum forms in its area and the pressure changes. Those swimming by are literally sucked into the mouth of the fish. Everything takes 6 milliseconds.

Reproduction and lifespan

Sea devil - fish, which merges with the partner in the literal sense of the word. A miniature male bites a female. It begins to secrete enzymes that ensure the fusion of the two bodies. Even blood vessels are united. Only the testicles remain “intact”.

Random photo of a sea devil that for some reason surfaced

One female can be bitten by several males. This is how the female gets the maximum supply of sperm. This mechanism ensured the devils' survival for millions of years. The species is considered relict.

The process of conception and childbirth in devil fish has not been studied in detail. The deep-sea lifestyle of anglerfish interferes. The animals are named this way because of the glowing “lanterns” on their faces. They swing in the water like floats, and the function of “tackle” is similar to that of a regular fishing rod.

American sea devil

Anglerfish begin to reproduce:

At the end of winter, if they live in southern latitudes.
In mid-spring or early summer, if they live in northern areas.
At the end of summer, if we're talking about about the Japanese anglerfish.

Monkfish eggs are folded into a ribbon 50-90 centimeters wide. The length of the canvas reaches 12 meters. The thickness of the tape is 0.5 centimeters and consists of:

mucus forming 6-sided compartments
the eggs themselves, enclosed one piece per compartment

Devil fish caviar ribbons drift freely in the water column. One sheet contains 1-3 million capsules with germs. Embryos are surrounded by fat. It prevents the masonry from settling to the bottom. The mucous cells are gradually destroyed, and the eggs float separately.

West Atlantic devil

The anglerfish fry that are born are not flattened on top, like adults. The cubs can be seen at the surface of the water, where they live for the first 17 weeks of life. Afterwards the animals sink to the bottom. Anglers have to live there for another 10-30 years, depending on the type of fish.

Features and habitat of the manta ray

Sea manta ray is a vertebrate animal, the only one of its kind, which has 3 pairs of active limbs. The width of the largest representatives of the species can reach 10 meters, but the most common are medium-sized individuals - about 5 meters.

Their weight fluctuates around 3 tons. On Spanish the word “scat” means blanket, that is, the animal got its name because of the unusual shape of the body.

Habitat a habitat manta ray- temperate, tropical and subtropical waters. The depth varies widely - from coastal areas to 100-120 meters.

It is generally accepted that the characteristics of the organism and the unusual shape of the body allow the manta to descend to depths of more than 1000 meters. Most often, the appearance near the coasts is associated with the change of seasons and time of day.

So, in spring and autumn, stingrays live in shallow water, but in winter they swim into open ocean. The same thing happens with the change of time of day - during the day animals are closer to the surface, at night they rush to the depths.

The body of the animal is a movable rhombus, since its fins are securely fused to the head. Manta ray pictured from above it appears as a flat, elongated spot gliding through the water. From the side you can see that the “spot” moves its body in waves and steers long tail. In addition to the photo, they are relevant manta ray vector images.

Mouth great manta ray located on its upper part, the so-called back. If the mouth is open, there is a “hole” gaping on the stingray’s body, about 1 meter wide. The eyes are there, on the sides of the head protruding from the body.

The photo shows a manta ray with its mouth open

The surface of the back is dark in color, most often brown, blue or black. The abdomen is light. There are also often white spots on the back, which in most cases have the shape of hooks. There are also completely black representatives of the species, the only bright spot in which is a small spot on the lower part.

Character and lifestyle of the manta ray

The movement of mantas occurs due to the movement of fins fused to the head. From the outside it looks more like a leisurely flight or soaring above the surface of the bottom than swimming. The animal looks calm and relaxed, however manta ray size still makes a person feel unsafe around him.

IN big water the slopes move mainly along a straight path, maintaining the same speed for a long time. Along the surface of the water, where the sun warms its surface, the stingray can slowly circle.

The largest manta ray can live in complete isolation from other representatives of the species, or can gather in large groups(up to 50 individuals). Giants get along well with other non-aggressive mammals.

An interesting habit of animals is jumping. Manta ray jumps out of the water and may even perform a somersault over its surface. Sometimes this behavior is widespread and one can observe the next or simultaneous somersault of several mantas at once.

One more interesting fact about the manta ray is that this giant must constantly be on the move, since its splashes are underdeveloped. The movement helps pump water through the gills.

Manta ray feeding

Almost any residents underwater world may become prey for manta rays. Representatives of the small-sized species feed on various worms, larvae, mollusks, small ones, and can even catch small ones. That is, medium and small manta rays absorb food of animal origin.

It is considered a paradox that giant stingrays, on the contrary, feed mainly on plankton and tiny ones. By passing water through itself, the stingray filters it, leaving prey and oxygen dissolved in the water. When “hunting” for plankton, the manta ray can travel long distances, although fast speed does not develop. average speed— 10 km/h.

Reproduction and lifespan of the manta ray

Reproductive system Stingrays are very developed and complex. Manta rays reproduce by ovoviviparous method. Fertilization occurs internally. The male is ready to mate when his body width reaches 4 meters; he usually reaches this size at the age of 5-6 years. The young female is 5-6 meters wide. Sexual maturity is the same.

The mating dances of stingrays are also a complex process. Initially, one or more males chase one female. This can continue for half an hour. The female herself chooses a partner for mating.

As soon as the male reaches the chosen one, he turns her upside down, grabbing her by the fins. The male then inserts the sexual organ into the cloaca. The stingrays occupy this position within a couple of minutes, during which fertilization occurs. Cases have been recorded in which several males performed fertilization.

The eggs are fertilized in the female's body and the young hatch there. At first, they feed on the remains of the “shell,” that is, the gall sac in which the eggs are located in the form of embryos. Then, when this supply runs out, they begin to receive nutrients from mother's milk.

Thus, the embryos live in the female’s body for about a year. A stingray can give birth to one or two babies at a time. This happens in shallow water, where they subsequently remain until they gain strength. The body length of a small stingray can reach 1.5 meters.

The manta ray is one of the most large fish peace. But, oddly enough, science knows surprisingly little about them.

text: Juliet Irmer

photo: Takako Uno and Stephen Wong

Four black and white giants emerge from the darkness of the ocean. On both sides, their flat bodies turn into wide fins, which they flap like wings. A school of fish flies in the water like a flock of birds.

Manta rays soar over the reef with their mouths wide open. One of them heads towards the divers and turns sharply right in front of them, showing its light belly. A flash flashes. Huge fish circle over the reef, and scuba divers signal each other to surface.

Two hours later, Andrea Marshall downloads the photos onto her computer. The thatch-roofed research station in Tofo, a village in southern Mozambique, is as hot as a greenhouse. The fan doesn't help. The sound of the surf can be heard from afar.

For ten years now, 31-year-old hydrobiologist Andrea Marshall has been studying the world's largest species of stingray. The manta ray, or giant sea devil, is one of the most... big fish on the ground. An adult stingray weighs up to two tons, the span of its lateral fins can reach seven meters - almost like a football goal.

There is only one species of manta ray, according to the Fish Catalog, a large three-volume reference book sitting on Marshall's shelf. But the marks on her world map tell a different story. The researcher marked the habitats of all known manta populations with red and blue dots. Blue color means one type, red means another. This map is her personal proof of the theory that there are not one, but two varieties of these fish.

Today's photographs taken by Marshall and her colleague, New Zealand biologist Simon Pearce, appear on the monitor. Three of the four stingrays they met were old acquaintances, to whom scientists assigned very American nicknames: Compass, 50 cents and Apple Pie. Scientists distinguish them by spots and scars on the belly and the lower part of the lateral fins. In each fish they form a unique pattern. For example, the 50-cent stingray has streaks on its belly that resemble the numbers “5” and “0,” and the right fin, bitten by a shark, curves in the shape of the letter “c,” which begins the word “cent.”

Marshall looks at photos of the fourth stingray. This is a female. Dark spots on her belly they look like a lion's paw print. The researcher compares the photo with photographs of other females in the database. There are no matches. Marshall names the newcomer Simba after the lion cub from The Lion King.

Simba is the 743rd stingray in her catalog. There are few manta ray populations in the entire world as large as here, off the coast of Mozambique, near the village of Tofo. None of them have been studied better than here.

Manta rays live in warm seas. The points on the map are concentrated at East Coast Australia, in the Pacific archipelagos, off the coast of California and in the Caribbean Sea. But most of them are in the Indian Ocean: off the East Coast of Africa, as well as off the coast of Thailand and Indonesia. How many manta rays live in the world's oceans? What are average duration their lives and habits? Science does not yet have a clear answer to all these questions.

Andrea Marshall was the first to describe the mating ritual of manta rays. During the breeding season, each female is relentlessly followed by up to 20 males. They, like a living train, repeat her every maneuver, until finally the female chooses one male. Pregnancy in manta rays lasts about a year, the female gives birth to one fry, the span of which reaches one and a half meters. From the very first minute of life, the little stingray is left to its own devices.

Relative to total body weight, manta rays have the largest brains of any fish. Many scientists believe that a gregarious lifestyle promotes brain growth. Mantas feed in groups and swim together for “hygienic procedures” in places where cleaner fish gather. It is assumed that in flocks of manta rays there is a hierarchy between older and younger individuals. Manta rays regularly emerge from the water and splash onto the sea surface. Marshall suggests that this is how they exchange signals. She generally considers manta rays to be very sociable creatures and is sure that there are individuals among them. Some are curious and playful, others are timid and indecisive.

Based on observations of manta rays off the coast of Mozambique, an American woman is trying to uncover other secrets of their behavior. About half of the recorded stingrays live here permanently, and Marshall regularly encounters them on dives. For example, she has already seen females Compass and 50 cents dozens of times. But in her database there are another hundred individuals that she observed off the coast of Mozambique, just one at a time over eight years. Is this a coincidence?

Andrea Marshall first came to Tofo ten years ago. Then she was still a hydrobiology student in Brisbane, Australia, and was interested in underwater photography. One of her friends advised her to dive off the coast of Mozambique.

Marshall grew up near San Francisco. She received her diving certificate at age 12; By the age of 15, she had logged half a thousand scuba dives. But nowhere in the world has she seen such a rich underwater world as off the coast of Mozambique. And most importantly, you could see stingrays here every day. At other popular dive sites, these fish must be tracked from an airplane.

Returning to Brisbane, Andrea Marshall decided to write her dissertation on manta rays. Professor Michael Bennett “looked at me like I was crazy. Of course, these animals are little studied. But there is an explanation for this: stingrays are rare, and their study is expensive pleasure. And in general: how can you write a dissertation in Africa at the age of 22?!” Marshall recalls.

But she decided to take a risk. After selling her car and furniture in Brisbane, Andrea flew to Mozambique. In the village of Tofo, she settled in a hut without water or light. The fishermen took her by boat to one of the reefs and then took her back. Later she was joined by a specialist whale sharks Simon Pearce. But in the early years, she constantly violated the main commandment of a diver - never dive alone.

Six months have passed since arriving in Tofo. One evening, while looking through photos of stingrays, Andrea Marshall noticed something strange. Some fish seemed to her larger and darker than others. “At first I thought they were older individuals,” she says. But she soon noticed other differences. It turned out that the giant manta rays fed and swam separately from the smaller rays. In addition, she rarely came across them, unlike the smaller manta rays that she saw every day. Does this mean that rays - like killer whales - are divided into two groups: sedentary and migratory? Over time, another possible explanation occurred to her.

A year and a half later, Andrea returned to Brisbane and shared a theory with her professor: there are two types of manta rays. “He didn’t even listen, but my other observations impressed him.” The dissertation topic was approved.

Andrea Marshall consulted five other stingray experts, but none of them supported her hypothesis. Manta rays are distributed almost throughout the world, and geographic isolation contributes to the formation of new biological species. It was unlikely that two species would have evolved in the absence of natural barriers, they argued. In addition, a comparative DNA analysis of manta rays did not reveal any differences. This is another argument against her theory.

It starts to bake at seven in the morning. Marshall looks out to sea from the shore. For the fourth day now, a long green cloud of phytoplankton has been stretching along the southern coast of Mozambique. These microscopic algae are at the beginning of the food chain of the World Ocean. We must wait for the wind to change and carry this mass out of the bay into the open sea. In troubled waters it is difficult to track her charges.

Marshall decides to try his luck. The day before, a group of divers noticed huge manta rays underwater. A researcher wants to install a satellite transmitter on one of the fish. She attaches miniature acoustic radio transmitters to the skin of smaller mantas. When a tagged stingray swims within 500 meters of a radio receiver, its transmitter signals are picked up and recorded. Marshall installed 12 radios along the 100-kilometer coastline in Tofo Bay. This way she can determine where the mantas swim most often.

But acoustic transmitters are not suitable for tracking migrating manta rays. Marshall considers those stingrays that she has met only once to be migratory. They appear as if from nowhere, spend a day or two in the bay and disappear. Where are they going? Where do they mate and produce offspring?

The researcher is trying to prove that giant manta rays roam the World Ocean in search of food. It has already equipped nine such stingrays with 20-centimeter satellite transmitters. Every time a manta ray comes to the surface, the device transmits the coordinates of the fish to the satellite. Each transmitter costs $5,000. And it is often lost a few months after installation.

The GPS navigator signals your arrival at given point. Andrea Marshall and Simon Pearce don scuba gear, take a camera and a meter-long copper spike to implant transmitters and dive into the sea. The current here is strong, visibility in the muddy water is limited. The underwater landscape with corals, crevices and caves seems to be covered in a veil. Scuba divers swim past reticulated moray eels, radiant lionfish and impressive potato grouper. And suddenly they stop.

To prove the existence of a new biological species, we need strong arguments. One of the main criteria is external differences. Biologists describe in detail the shape and structure of the animal’s body, its organs, coloring and lifestyle. This description is almost always accompanied by genetic analysis data.

In 2007, Marshall did without them. By then, she had been studying manta rays off the coast of Mozambique for almost five years, having completed 1,300 dives. She traveled to Mexico, Thailand and Ecuador to research local manta populations. More and more points appeared on her map. She marked the habitats of small mantas in red, and the habitats of giant mantas in blue. But her hypothesis about the existence of two species of these fish remained unconfirmed.

In May 2007, she went to Indonesia, where commercial fishing for giant manta rays is underway off the coast of the island of Lombok. She needed one specimen for anatomical research. At a local market, with the help of fishermen, she turned over the carcass of a stingray and noticed a protrusion at the base of the tail. She carefully cut the skin. And she was stunned.

The ancestors of manta rays had a poisonous spike on their tail; in some species of stingrays it is still preserved. And among manta rays it disappeared during evolution. So, in any case, scientists thought. Small manta rays really don't have it. But sticking out of the tail bones of a giant manta ray at a market on the island of Lombok was... a sharp protrusion several millimeters long - a miniature spike. “Finally, I found a 100% anatomical difference!” - says Marshall.

The luck continued. Marshall named the first two giant manta rays for which she installed satellite transmitters after the great navigators Cook and Magellan. Cook lost the transmitter three weeks later, but Magellan sailed 1,100 kilometers south along the coast of Mozambique in two months and lost the transmitter just past Durban (South Africa). This confirmed Marshall's assumption that giant manta rays are "ocean wanderers." The results of genetic tests proved her right. There are actually two types of manta rays in the world.

In July 2008, Andrea Marshall presented a report on her many years of research at the Congress of Hydrobiologists in Canada. The genus "manta", she declared, includes two species - giant manta ray (manta birostris) and the smaller reef manta (manta alfredi). After her speech, silence fell in the hall.

With her hair wet from her dive, Andrea Marshall sits down at the table. Today's searches were fruitless; he and Pierce did not find a single “giant” under water. But fate is already throwing the researcher new challenge. Andrea takes out a world map. Recently, along with red and blue dots, yellow marks have appeared on it. They are concentrated in the Gulf of Mexico and the Caribbean Sea.

One day, on the Internet, she found a photo of a stingray that may be a representative of a third species of manta, Marshall says. “I saw a photo of a manta ray and thought: wow, I don’t know one like that!”

photo: filipmije (on and off)

The animal is not endowed with anything that could be used as protection against sea predators. No huge teeth, no spines, no ability to shock like stingrays do. Manta rays often become victims of other ocean inhabitants. Large sharks especially like to hunt them. If in the middle of the last century people considered the Sea Devil dangerous to humans, now everyone knows that there is no need to be afraid of them.

photo: Tim

The main food of the Sea Devil is plankton, small fish and larvae. Just like whales, manta rays open their mouths wide to swallow their small prey and then filter the water to leave the food in their mouths.
Manta rays are very smart. Their brain size exceeds that of stingrays and sharks. They are easy to tame and are loved by divers. Some tourists specifically go on holiday to the coast Indian Ocean to swim side by side with the Sea Devil. These animals are very curious and, when they see something interesting on the surface of the water, they swim up to it to observe what is happening. Sometimes such excessive curiosity turns out to be destructive for this harmless creature.

photo:Saschj

One of the mantas’ favorite pastimes is jumping over the water to a height of one and a half meters. The landing of the massive animal can be heard for many kilometers. The purpose of such games is not clear, but perhaps in this way the Sea Devil attracts the attention of the opposite sex or tries to stun the small fish that are part of its diet.
The appearance of Manta cubs is a rare occurrence. The female gives birth to only one baby. His height at birth is a full meter! A little sea devil is born in the form of a curled tube, but, once outside the mother’s womb, it instantly spreads its wings. From this moment on, he begins to “fly” around his mother in circles.

photo: Steve Dunleavy

You can see the Manta ray in aquariums. But there are only five such places in the whole world, because the size of an aquarium for such a massive marine animal must be quite large. It is wonderful that manta rays also reproduce in captivity, because this way they will not become extinct, given that they rarely give birth to their own kind. Breeding Sea Devils in captivity is not easy and time consuming, but it is worth it. One Little Sea Devil was born in an aquarium located in Japan. The event took place in 2007 and was covered on television. Man's love for this animal, responsive to affection, came somewhat late, and now the Manta is considered one of the most unique animals on the planet.