Sexual dimorphism in all its glory. Demonstrates it fish devil... The males and females of this deep-sea creature, as if from different worlds... Females reach 2 meters in length and have a lantern outgrowth on their heads.
A fish sea Devil
It shines in the water column, attracting prey. Devil males are 4 centimeters long, lacking lighting fixture... This is not the only one interesting fact about deep sea creation.
Description and features of the devil fish
Devil fish in the photo seems awkward. Many are repulsed by the appearance of the animal, for which it was compared to the devil. Devil fish are distinguished from standard fish:
- Flattened body. It was as if they had stepped on him from above.
- Big head. It accounts for 2 thirds of the animal.
- A kind of triangular body, sharply tapering towards the tail.
- Almost imperceptible gill slits.
- Wide mouth, swinging open in the entire circumference of the head. The upper jaw is more mobile than the lower one. The latter is pushed forward. The fish has a kind of snack.
- Sharp and curved teeth.
- Flexibility and mobility of the jaw bones. They move apart, like those of snakes, making it possible to swallow prey larger than the hunter himself.
- Small, round and close-set eyes. They are reduced to the bridge of the nose, like a flounder.
- Two-piece dorsal fin. His rear part is at the tail and soft. The anterior fin region has 6 rigid spine ribs. Three of them go over the head. The anterior ray is shifted towards the jaw and has a thickening. It is called eska and is home to luminous bacteria.
- The presence of skeletal bones in the pectoral fins. This partially gives them the function of the legs. Devils move on fins along the bottom, crawling or jumping in a peculiar way. Ability to swim sea devils are also not deprived. The fins also help to burrow into the ground, hiding from prying eyes.
Caspian Sea Devil
Devil fish food
All sea devils are predators. As an exception, fish rise to the surface of the water, hunting herring and mackerel. Sometimes sea devils grab birds swaying on the waves. But usually bottom predators hunt at the bottom, catching there:
Bearded devil
- squid and other cephalopods
- gerbils
- stingrays
- cod
- flounder
- eels
- small sharks
- crustaceans
The devils wait for the victims of the fish, hiding at the bottom. The light of the predator's "lantern" attracts the inhabitants of the depths. When potential victims offend the escu, the devil opens his mouth sharply. A vacuum forms in its area, the pressure changes. Those floating by are literally sucked into the mouth of the fish. Everything about everything takes 6 milliseconds.
Reproduction and life expectancy
Sea devil - fish, which merges with a partner in the truest sense of the word. A miniature male bites a female. That begins to secrete enzymes that ensure the fusion of two bodies. Unite even blood vessels... Only the testicles remain "intact".
Random photo sea devil, who for some reason floated to the surface
One female can be bitten by several males. So the female receives the maximum sperm supply. This mechanism has ensured the survival of the devils for millions of years. The species is considered relict.
The process of conception and childbearing in fish devils has not been studied in detail. The deep-sea lifestyle of anglers interferes. So the animals are called because of the "flashlights" glowing on their faces. They swing in the water like floats, and the "tackle" function is similar to an ordinary fishing rod.
American sea devil
Anglers start breeding:
- At the end of winter, if they live in southern latitudes.
- In the middle of spring or early summer, if they live in northern areas.
- At the end of summer, if it comes about the Japanese angler.
Eggs monkfish folded into a tape 50-90 centimeters wide. The length of the canvas reaches 12 meters. The tape is 0.5 centimeters thick and consists of:
- mucus forming 6-sided compartments
- the eggs themselves, enclosed one by one in the compartment
Caviar ribbons of fishes of devils freely drift in the water column. One canvas contains 1-3 million capsules with embryos. The embryos are surrounded by fat. It does not allow the masonry to settle to the bottom. The mucous cells are gradually destroyed, and the eggs float separately.
West atlantic devil
Anglerfish fry that are born are not flattened from above, like adults. You can see the cubs near the surface of the water, where they live for the first 17 weeks of life. After that, the animals sink to the bottom. Anglers will have to live there for another 10-30 years, depending on the type of fish.
Monkfish, or angler fish, is a predatory sea bottom fish, which belongs to the class of ray-finned fish, subclass newfin fish, infraclass bony fish, angler-shaped order, angler-shaped suborder, angler-shaped suborder, angler-fish family, angler-fish genus (large angler-fish), or angler-fish (lat.Lophius ).
Etymology of the Latin name monkfish not fully understood. Some scholars are of the opinion that it comes from the modified Greek word "λοφίο", meaning a ridge that resembles the jaws of this fish. Other researchers associate it with a kind of ridge that runs along the entire back. The popular name "angler" appeared due to the long and modified first ray of the dorsal fin, equipped with a bait (eskoy) and resembling a fishing rod of a fisherman. And due to the unusual and unattractive appearance of the head of the predator, he was nicknamed "the monkfish". Due to the fact that angler fish can move along the seabed, pushing off from it with slightly modified fins, in some countries anglers call them.
Monkfish (fish) - description, structure, photo. What does a monkfish look like?
Monkfish are rather large predatory fish that live on the bottom and reach a length of 1.5-2 meters. The monkfish weighs 20 kilograms or more. The body and huge head with small branchial slits are rather flattened in the horizontal direction. In almost all anglerfish species, the mouth is very wide and opens almost along the entire circumference of the head. The lower jaw is less mobile than the upper one, and is slightly pushed forward. The predators are armed with rather large sharp teeth that are bent inward. Thin and flexible jaw bones enable fish to swallow prey that is almost twice as large.
The eyes of the monkfish are small, set close to each other, and are located on the top of the head. The dorsal fin consists of two divided parts, one of which is soft and shifted towards the tail, and the second is composed of six rays, three of which are located on the head itself, and three immediately behind it. The anterior spiny ray of the dorsal fin is strongly shifted to the upper jaw and is a kind of "rod", at the top of it there is a leathery formation (esca), in which luminous bacteria live, which are a bait for potential prey.
Due to the fact that the pectoral fins of the monkfish are reinforced with several bones of the skeleton, they are quite powerful and allow the fish not only to burrow into the bottom soil, but also to move along it by crawling or using peculiar jumps. The pelvic fins are less in demand during the movement of the angler fish and are located on the throat.
It is noteworthy that the body of the anglerfish, painted in dark gray or dark brown colors (often with randomly spaced light spots), is covered not with scales, but with various thorny outgrowths, tubercles, long or curly leathery fringes similar to algae. This camouflage allows the predator to easily ambush in the thickets of algae or on the sandy bottom.
Where does the anglerfish (anglerfish) live?
The distribution area of the anglerfish genus is quite extensive. It includes the western waters of the Atlantic Ocean, washing the shores of Canada and the United States of America, the eastern Atlantic, whose waves beat against the shores of Iceland and the British Isles, as well as the cooler depths of the North, Barents and Baltic seas... Certain species of monkfish are found off the coast of Japan and Korea, in the waters of the Okhotsk and Yellow Seas, in the Eastern Pacific Ocean and in the Black Sea. Anglers also live in the depths of the Indian Ocean, covering the southern tip of the African continent. Depending on the species, monkfish live at depths from 18 meters to 2 kilometers or more.
What does the anglerfish eat?
By way of feeding, sea devils are predators. Their diet is based on fish that live in the bottom water column. Gerbils and small rays and small sharks, eels, flounders, cephalopods(squid, cuttlefish) and various crustaceans. Sometimes these predators rise closer to the surface of the water, where they hunt herring or mackerel. In particular, there were cases when anglers even attacked birds peacefully swaying on the sea waves.
All monkfish hunt from ambush. Thanks to natural camouflage they cannot be noticed when they lie motionless at the bottom, buried in the ground or hiding in thickets of algae. Potential prey is attracted by a luminous bait, which is located at the anglerfish at the end of a kind of rod - an elongated ray of the front dorsal fin. At the moment when crustaceans, invertebrates or fish swimming past touch the esca, the anglerfish sharply opens its mouth. As a result of this, a vacuum is formed, and the stream of water, together with the prey that has no time to do anything, rushes into the mouth of the predator, because the time it takes does not exceed 6 milliseconds.
Taken from the site: bestiarium.kryptozoologie.net
Waiting for prey, the angler fish is capable of for a long time stay absolutely still and hold your breath. The pause between breaths can last from one to two minutes.
It used to be thought that the angler's rod with bait, movable in all directions, serves to attract prey, and anglers open their big mouth only when curious fish touch the esque. However, scientists were able to establish that the mouth of predators automatically opens, even if the bait is touched by any object floating by.
Angler fish are rather greedy and voracious. This often leads to their death. Having a mouth and stomach large sizes, anglerfish is able to capture large enough prey. Because of the sharp and long teeth, the hunter cannot let go of his prey, which does not fit in his stomach, and chokes on it. There are cases when fishermen found prey in the stomach of a caught predator only 7-10 cm less than the angler itself.
Types of monkfish (anglers), names and photos.
The genus of angler fish (lat.Lophius) today includes 7 species:
- Lophius americanus (Valenciennes, 1837) - American anglerfish (American monkfish)
- Lophius budegassa (Spinola, 1807) - black-bellied angler, or southern European angler, or budegasse angler
- Lophius gastrophysus (Miranda Ribeiro, 1915) - West Atlantic anglerfish
- Lophius litulon (Jordan, 1902) - Far Eastern anglerfish, yellow anglerfish, Japanese anglerfish
- Lophius piscatorius (Linnaeus, 1758) - European monkfish
- Lophius vaillanti (Regan, 1903) - South African angler
- Lophius vomerinus (Valenciennes, 1837) - Cape (Burmese) monkfish
Below is a description of several types of angler fish.
- Is dimesal (bottom) predatory fish, having a length of 0.9 m to 1.2 m with a body weight of up to 22.6 kg. Due to its huge rounded head and body tapering towards the tail, the American anglerfish resembles a tadpole. The lower jaw of the large, wide mouth is strongly protruded forward. It is noteworthy that even with a closed mouth, the lower teeth of this predator are visible. Both the upper and lower jaws are literally dotted with sharp, thin teeth, inclined deep into the mouth and reaching a length of 2.5 cm.It is interesting that in the lower jaw almost all monkfish teeth big size and are arranged in three rows. On the upper jaw, large teeth grow only in the center, and in the lateral areas they are smaller, in addition, there are small teeth at the top. oral cavity... The gills, devoid of lids, are located just behind the pectoral fins. Monkfish eyes small size directed upwards. Like all anglers, the first ray is elongated and has a leathery growth that glows due to bacteria that have settled there. The leathery covers of the back and sides are colored in chocolate brown tones of various shades and are covered with small light or dark spots, while the belly is off-white. The life expectancy of this species of monkfish can reach 30 years. The distribution area of the American anglerfish includes the northwestern part of the Atlantic Ocean with depths of up to 670 m, stretching from the Canadian provinces of Newfoundland and Quebec to the northeastern coast of the North American state of Florida. This predator thrives in waters with temperatures ranging from 0 ° C to + 21 ° C on sandy, gravelly, clayey or silty bottom sediments, including those covered with destroyed shells of dead mollusks.
- reaches a length of 2 meters, and the weight of individual individuals exceeds 20 kg. The entire body of these predators is flattened from the back to the belly. The size of a wide head can be 75% of the length of the entire fish. The European monkfish has a huge mouth, resembling a crescent moon, with large quantity thin, pointed, slightly crooked teeth, and the lower jaw, which is significantly protruded forward. Slotted branchial openings are located behind wide, reinforced with skeletal bones pectoral fins that allow European anglers to move or burrow in the bottom. The soft, scaleless body of these bottom fish covered with various bone spines or leathery growths of various lengths and shapes. The same beard-like "adornments" border the jaws and lips, as well as the lateral surface of the head of the European monkfish. The posterior dorsal fin is opposite the anal. The anterior dorsal fin consists of 6 rays, the first of which is located on the head of the angler fish and can reach a length of 40-50 cm. There is a leather “pouch” on its top that glows in the dark layers of the bottom water. The color of individuals varies somewhat depending on the habitats of these fish. The back and sides, covered with dark spots, can be colored brown, reddish or greenish-brown, in contrast to the belly, which is white. The European monkfish lives in the Atlantic Ocean, washing the shores of Europe, from the coast of Iceland to the Gulf of Guinea. These "cute creatures" can be found not only in the cold waters of the Northern, Baltic and Barents Seas or in the English Channel, but also in the warmer Black Sea. European angler fish live at depths of 18 to 550 m.
- In structure and shape, this species of marine fish is very close to its European congener, but in contrast to it, it has a more modest size and a head that is not so wide relative to the body. The length of the monkfish ranges from 0.5 to 1 meter. The structure of the jaw apparatus is no different from individuals of other species. This species of monkfish gets its name from its characteristic black peritoneum, while its back and sides are colored in various shades of reddish brown or pinkish gray. Depending on the habitat, the body of some individuals may be covered with dark or light spots. Leathery outgrowths of a yellowish or light sandy color, bordering the jaws and head of the black-bellied anglerfish, are short and rarely located. The life span of the black-bellied monkfish does not exceed 21 years. This species is widespread in the waters of the eastern part of the Atlantic Ocean throughout the entire space - from Great Britain and Ireland to the coast of Senegal, where the anglerfish lives at depths from 300 to 650 m.The black-bellied anglerfish can also be found in the waters of the Mediterranean and Black Seas at a depth of up to 1 kilometers.
- is a typical inhabitant of the waters of the Japan, Okhotsk, Yellow and East China Seas, as well as a small part of the Pacific Ocean off the coast of Japan, where it occurs at depths ranging from 50 m to 2 km. Individuals of this species grow up to 1.5 meters in length. Like all representatives of the genus Lophius, the Japanese monkfish has a horizontally flattened body, but unlike its relatives, it has more a long tail... Sharp teeth bent towards the pharynx in the lower, forward jaw, are arranged in two rows. The leathery body of the yellow anglerfish, covered with numerous outgrowths and bony tubercles, is painted in a monochromatic brown color, over which light specks with a darker outline are scattered chaotically. In contrast to the back and sides, the belly of the Far Eastern sea devils is light. The dorsal, anal and pelvic fins are dark in color, but the tips are light.
- Cape Angler, or Burmese monkfish (lat.Lophius vomerinus) it is distinguished by a huge flattened head and a rather short tail, which occupies less than one third of the length of the whole body. The size of adults does not exceed 1 meter. Their life expectancy is no more than 11 years. The Cape Anglerfish lives at depths ranging from 150 to 400 m in the southeastern Atlantic and western Indian Ocean, along the coasts of Namibia, Mozambique and the Republic of South Africa. The light brown body of the Burmese monkfish is strongly flattened from the back towards the abdomen and is fringed with numerous leathery growths. Esca at the top long first ray of the dorsal fin, resembles a shred. The gill slits are located behind the pectoral fins and just below their level. The lower part of the body (abdomen) is lighter, almost white.
Stingray - stingray Manta Ray. Manta ray(another name for the giant "sea devil") can reach sizes up to 7 m, from the tip of one lateral fin to the tip of the other (the transverse width of the slope). The weight of such rays is up to 2.5 tons. The usual average sizes for mantas are 4-4.5 m. Scientific name species - Manta birostris. The manta ray belongs to the mantle family, or sea devils. The flat body of the stingray has a rhomboid shape, which continues on the sides with fins, behind a long thin tail. Therefore, it refers to the stingray, they also say stingray, because of the spiny spines at the end of the tail. According to hydrobiologist Andrea Marshall, who has been studying manta rays for over 10 years, manta rays actually come in two subspecies. But it is officially recognized to count one type of mantas. Manty live in tropical waters of all oceans. The most studied population is off the coast of Mozambique. Manty in the water is mesmerizingly beautiful. The top is black, with a bright white belly, on which there are dark spots characteristic of each individual. Manty move slowly, movements are unhurried and graceful, mantas seem to float in the water. Unlike other stingrays, mantas prefer to stay in the upper layers of water, sometimes they lie on the surface with their pectoral fin exposed from the water.
Manty belong to the class cartilaginous fish like sharks. Manty feed on plankton, small crustaceans and small fish. Moving behind plankton, they can cover huge distances, although the speed of manta rays is not high, about 10 km / h. There is a large oral cavity in front of the head, up to 1 m in diameter when the mouth is open. On the sides of the mouth, manta rays have fins, with which they direct the flow of water into the mouth. Because of these blades-horns, which during movement can twist in spirals, and the black color of the back, they received the nickname "sea devils" at one time. The water is filtered through a filtering apparatus, the gill slits are like those of whale sharks. Anything that gets stuck goes into food. Mantas have the largest fish brains, in relation to the mass of the whole body. The female manta ray bears one cub for almost 12 months. Unusually, being in the womb, the baby feeds on her milk. A fry weighing up to 10 kg with a transverse size of fins up to 1.5 m is born, fully adapted to independent life in water. During the courtship period, several males follow the line, sometimes up to 20 individuals, until the female chooses one. Manti mate at a depth of one to several meters. In life, they prefer to keep in groups, not far from coral reefs. Manta rays, like sharks, can be accompanied by adherent fish, which cleanse the skin of manta rays from the invading organisms. But all the same, mantas regularly go to the reefs in groups for "fish cleaning" like many large sea fish... Manta rays are curious and not aggressive in nature.
They love to jump out of the water. Why they are doing this is not completely clear. In a jump, they rise up to 1.5 m into the air, then simply flop back into the water. The sound of a stingray hitting the water surface is heard several miles away. If there are divers in the water or there is a boat, then the manta ray can swim up out of curiosity. The only danger is that after jumping out, the manta ray can fall from above onto the boat or the swimmer. The urge to jump is contagious when one is jumping
The manta ray gained world fame thanks to its huge size... In the widest part of the body - from one fin tip to the other - it can reach 7 meters. Moreover, its weight is about 2 tons.
Manty live in everyone warm seas and tropical waters of the Pacific and Atlantic oceans including the Mediterranean.
The second name - "sea devil" - manta rays received for the head fins, located along the edges of the mouth. During swimming, they twist into a tube and become like horns. These fins are essential for the stingray to hunt. While swimming, he directs them into his mouth a stream of water rich in plankton and small fish.
In search of food, they travel long distances. Like the whale shark, which, incidentally, is its closest relative, mantas suck in water and pass it through many gill plates. After filtration, plankton and small fish remain on them. Then the entire catch is sent to the stomach.
Bottom view
Manty, unlike other stingrays, most spend their lives in the upper layers open sea... Their swimming is mesmerizing. It can be compared to the soaring flight of a huge bird in the air. The movements of its huge pelvic fins are so smooth and proportionate. Sometimes sea devils can be seen lying on the surface of the water.
In the habitats or migrations of these animals, sometimes an incredible sight unfolds above the surface of the water - the quick jumping of these giants from the water and a deafening landing with a fountain of splashes. Sometimes the rumble from these jumps is heard at a distance of several kilometers. No one can say for sure what the purpose of these jumps is, but there is an assumption that in this way they attract partners or stun flocks of small fish.
In these places, you need to be careful not to swim close to their flock, as one of them may accidentally fall on a small boat and sink it. This is the only threat that can come from this underwater inhabitant.
One of these cases happened quite recently - at the end of March this year, when, while on vacation in Florida, on a small yacht that I rented married couple with children, a giant ramp jumped up and pressed the woman with all its mass. But everything ended well. The victim escaped with fright and a couple of bruises, and the stingray was released back into the sea.
Previously, people believed that the stingray deliberately attacks divers, clasping them with its huge fin, like a cloak, and dragging them to the bottom. By the way, it is for this reason that the stingray got its name "manta", which is translated from Spanish as "cloak".
Small flock of stingrays
The discovery of this animal took place in 1792 and belongs to Johann Julius Walbaum, a German physician, naturalist, zoologist and taxonomist.
Little is known about the breeding process of these rays. The female gives birth to one cub, about 125 cm wide and 10 kg in weight. While he is in the womb, he feeds on her milk. Childbirth is happening very rapidly. The baby, one might say, flies out of the womb, rolled up into a tube. Then he spreads his fins and, together with the female, sets off on a journey around the world.
29 Mar SKAT MANTA
The largest stingray
Translated from Spanish, the name of this fish is translated as "cloak" or "blanket". And indeed, floating in the thick clear water manta rays are very reminiscent of a kind of flying carpet, elegantly and majestically soaring in the sky.
Manta (Manta birostris) is one of the most famous species of rays. It owes its fame, first of all, to its enormous size and amazing appearance, which have caused the appearance of various legends, stories and fables about this amazing fish since ancient times.
The appearance and size of the manti are really unique. Even a newborn "mantenok" reaches more than 150 cm in fins span, and an adult can reach almost 8 m in wingspan with a weight of more than 2 tons! This is a real sea giant.
For the sake of fairness, it should be said that the manta ray is not the record holder among stingrays in body length - the "podium" in this competition is occupied by saw-nosed rays, some species of which reach 7.6 m from the tip of the snout to the tip of the tail. The body of the manta ray does not grow longer than the 2 meter mark. But due to the massiveness and breadth of the wingspan of the fins, the manta ray, according to the unanimous opinion of biologists, is considered the largest stingray known to science.
Despite the fact that these stingrays have been known to people since time immemorial, their way of life has not been studied enough.
V old days various tales circulated about the bloodthirstiness of manta rays. It was believed that the stingray is able to capture a person in the arms of its huge wings, strangle and eat, or even swallow him whole. It is not for nothing that the popular name of the mantas is stuck - sea devils. These fables are completely groundless. Manta does not belong to aggressive species of marine animals and never attacks humans, like the whale shark.
Following the accumulations of plankton, these giant stingrays can make very long journeys across the ocean - up to several thousand kilometers. However, this is also characteristic of other planktivorous giants of the sea.
The manta ray belongs to the order Dasyatiformes tail-shaped (according to other sources - to the order of eagles - Myliobatidae). These fish are represented the only kind in the genus Manta (Manta) of the Mantle family.
The taxonomists still cannot come to a consensus about the existence of some orders of stingrays. Some sources indicate the existence of a detachment of eagle rays, which include a family of stingrays, according to the taxonomy presented by other scientific sources, a detachment of stingrays is distinguished, in which eagle rays are represented by a separate family. However, for the level of knowledge about stingrays, which aims to convey this site to visitors, such disagreements between scientists are not significant.
Giant sea devils
The manta ray is one of the largest fish in the world. But, oddly enough, it is about them that science knows surprisingly little.
Four black and white giants emerge from the darkness of the ocean. On both sides, their flat bodies merge into broad fins, which they flap like wings. A flock of fish flies in the water like a flock of birds. With their mouth wide open, manta rays hover over the reef. One of them heads towards the divers and turns sharply right in front of them, showing its light belly. A flash flashes. Huge fish circling the reef, and scuba divers signal each other to surface. Two hours later, Andrea Marshall downloads the photos to a computer. The reed-covered research station in Tofo, a hamlet in southern Mozambique, is stuffy like a greenhouse. The fan does not help. The sound of the surf can be heard from afar. For a decade, 31-year-old hydrobiologist Andrea Marshall has been studying the world's largest stingray species. Manta, or giant sea devil, is one of the largest fish on Earth. 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 kind of manta ray, according to the Fish Catalog, a large three-volume reference book on Marshall's shelf. But the marks on her world map tell a different story. The researcher marked the habitats of all known populations of manta rays with red and blue dots. Blue color means one kind, red means another. This map is her personal proof of the theory of the existence of not one, but two species 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 are old acquaintances to whom scientists have appropriated quite 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. They form a unique pattern for each fish. For example, on a 50 cent stingray, the stains on the belly resemble the numbers "5" and "0", and the right fin bitten by a shark bends in the form of the letter "c", with which the word cent ("cent") begins.
Marshall looks at the photographs of the fourth ray. This is a female. The dark spots on her belly are like the prints of a lion's paw. The researcher compares the picture with photographs of other females from the database. No matches. Marshall names rookie Simba after the lion cub from The Lion King.
Simba is the 743rd stingray in her catalog. There are only a few populations of manta rays as large in the world as here, off the coast of Mozambique, near the village of Tofo. None of them has been better studied here.
Mantas live in warm seas. Points on the map are centered at East coast Australia, in the Pacific archipelagos, off the coast of California and in the Caribbean. But most of them are in Indian Ocean: off the east coast of Africa, as well as off the coast of Thailand and Indonesia. How many manta rays are there in the 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 marriage ritual 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 the fins of which reaches one and a half meters. From the very first minute of life, the little stingray is left to itself.
Relatively total weight the body of manta rays is the largest brain among all fish. Many scientists believe that the gregarious lifestyle promotes brain growth. Mantas feed in groups and swim together for "hygiene procedures" in places where cleaner fish accumulate. It is assumed that in flocks of manta rays there is a hierarchy between older and younger individuals. Mantas regularly emerge from the water and flop down on the sea surface with a splash. Marshall suggests that this is how they exchange signals. She generally considers mantas to be very sociable creatures and is sure that there are personalities among them. Some are curious and playful, others are timid and indecisive. Based on observations of manta rays off the coast of Mozambique, the American is trying to uncover other secrets of their behavior. Approximately half of the counted stingrays live here permanently, Marshall regularly meets them when diving. For example, she had already seen Compass and 50 cents females dozens of times. But in her database there are another hundred individuals, which she observed off the coast of Mozambique in just one in eight years. Is this a coincidence? Andrea Marshall first came to Tofo ten years ago. Then she was still a student hydrobiology in the Australian Brisbane and was fond of underwater photography. Someone from her acquaintances advised her to dive off the coast of Mozambique. Marshall grew up near San Francisco. She received her diving certificate at the age of 12; by the age of 15, she had half a thousand scuba diving on her account. But nowhere in the world has she seen so rich underwater world like off the coast of Mozambique. And most importantly, here you could meet stingrays every day. In other popular diving sites, these fish need to be tracked from an airplane.
Back in 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 poorly understood. But there is an explanation for this: stingrays are rare, and studying them is expensive. And in general: how can you write a dissertation in Africa at 22 ?! " - recalls Marshall. But she decided to take a chance. After selling a car and furniture in Brisbane, Andrea flew to Mozambique. In the village of Tofo, she settled in a hut without water or light. Fishermen took her by boat to one of the reefs, and then took her back. Later she was joined by a specialist in 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 at pictures of stingrays, Andrea Marshall noticed something strange. Some fish seemed to her larger and darker than the rest. “At first I thought they were older specimens,” she says. But she soon noticed other differences as well. It turned out that the giant mantas fed and swam apart from the smaller rays. In addition, she rarely came across them, in contrast to the smaller mantas, which she met every day. Does this mean that rays - like killer whales - are divided into two groups: sedentary and migratory? Over time, another possible explanation came to her mind. After a year and a half, Andrea returned to Brisbane and shared her 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 with five other ray specialists, but none of them supported her hypothesis. Manta rays are distributed almost all over the world, and the formation of new biological species is facilitated by geographic isolation. It is unlikely that, in the absence of natural barriers, two species have evolved, they argued. Moreover, with comparative analysis No differences were found in the DNA of the manta rays. This is another argument against her theory. It starts to bake already at seven in the morning. Marshall looks from the shore into the sea. For the fourth day along south coast Mozambique has a long green cloud of phytoplankton. These microscopic algae are at the beginning of the oceans' food chain. We must wait for the wind to change and carry this thick from the bay to the open sea. V muddy water difficult to track down her charges.
Marshall decides to try his luck. The day before, a group of divers noticed huge mantas under the water. The researcher wants to install a satellite transmitter on one of the fish. On the skin of the smaller manta rays, she attaches miniature acoustic radio transmitters. When the tagged skate swims within a radius of 500 meters from the radio, the signals from its transmitter are captured and recorded. Marshall has installed 12 radios along the 100-kilometer coastline in Tofo Bay. So she can determine where mantas swim most often.
But acoustic transmitters are not suitable for tracking migrating manta rays. As migratory, Marshall considers those stingrays that she has met only once. They appear as if from nowhere, spend a day or two in the bay and disappear. Where do they go? Where do they mate and produce offspring?
The researcher is trying to prove that giant manta rays roam the oceans in search of food. It has already supplied nine of these stingrays with 20cm satellite transmitters. Each time a manta ray floats to the surface, the device transmits the coordinates of the fish to the satellite. Each transmitter costs $ 5,000. And it is often lost within a few months after installation.
The GPS navigator signals the arrival at the specified point. Andrea Marshall and Simon Pearce don scuba gear, take a camera and a meter long copper lance to implant transmitters and dive into the sea. The current is strong and visibility is limited in muddy waters. The underwater landscape with corals, crevices and caves seems to be covered with a veil. Scuba divers swim past a mesh moray eel, a radiant lionfish and an imposing potato grouper. And suddenly they stop.
To prove the existence of a new biological species, strong arguments are needed. One of the main criteria is external differences... Biologists describe in detail the shape and structure of the animal's body, its organs, color 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 nearly five years, having completed 1,300 dives. She traveled to Mexico, Thailand and Ecuador to research local manta ray populations. More and more points appeared on her map. In red, she marked the habitats of small mantas, and in blue, the places where gigantic ones were spread. But her hypothesis about the existence of two species of these fish remained unconfirmed.
In May 2007, she went to Indonesia, where industrial fishing for giant manta rays is carried out off the coast of the islet of Lombok. She needed one copy for anatomical research... At the local market, with the help of fishermen, she turned the stingray carcass and noticed a ledge at the base of the tail. She slit the skin gently. And she was stunned.
The ancestors of mantas on their tail had poisonous thorn; in some species of stingrays, it has survived to this day. And in mantas it disappeared in the course of evolution. So, in any case, scientists believed. Small mantas really don't have it. But from the tail bones of a giant manta ray in the Lombok island market stuck out ... a sharp protrusion several millimeters long - a miniature spike. “Finally I found a 100% anatomical difference!” says Marshall.
The luck continued. The first two giant mantas, which she installed satellite transmitters, Marshall named after the great seafarers Cook and Magellan. Cook lost the transmitter three weeks later, but Magellan sailed 1100 kilometers south along the coast of Mozambique in two months and lost the transmitter beyond Durban (South Africa). This confirmed Marshall's suggestion that giant manta rays were "ocean wanderers." The results of genetic tests proved her correctness. There are really two types of mantas in the world.
In July 2008, Andrea Marshall presented a paper on her many years of research at the Congress of Hydrobiologists in Canada. The genus "manta", she announced, includes two species - the giant manta ray (manta birostris) and the smaller reef manta ray (manta alfredi). After her speech, there was silence in the hall.
Andrea Marshall sits down at the table, her hair wet from the dive. Today's searches were unsuccessful, he and Pierce did not find a single "giant" under water. But fate is already casting new challenge... Andrea pulls out a map of the world. Recently, along with red and blue dots, yellow marks have appeared on it. They are concentrated in Gulf of Mexico and the Caribbean.
Once on the Internet, she found a snapshot of a stingray, which may turn out to be a representative of a third species of manta rays, says Marshall. “I saw a photo of a manta ray and thought: wow, I don’t know such a thing!”
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