Sea fox shark. Sea fox: not an animal, but a fish. Sea fox = Alopias vulpinus
This species is also known as the sea fox, sea fox shark and sea fox. The habitat extends to tropical and temperate waters. In the Atlantic Ocean, these cartilaginous fish live from Newfoundland to Argentina and from the North Sea to the southern tip of Africa. Found in the Mediterranean. In the Indian Ocean, they are common in its northern part. And in the Pacific Ocean, the fox shark has chosen for itself the zone from Japan to New Zealand and from British Columbia to Chile.
This species is subject to seasonal migrations. It moves to northern latitudes along with warm masses of water. At the same time, the range of movement of males is more extensive compared to females. It is assumed that the populations of the Atlantic, Pacific and Indian Oceans have different life cycles. This is indirectly indicated by the fact that there are no ocean-to-ocean migrations. Representatives of the species are deep-sea and live at a depth of up to 550 meters. Only young sharks are sometimes found near the shore.
Description
The body is streamlined, torpedo-shaped with a short wide head. The eyes are medium in size, there are no urination membranes on them. The mouth is small, its shape is curved. There are 35-52 rows of teeth on the upper jaw, and 26-49 such rows on the lower jaw. The teeth are small, triangular in shape and have no serrations. There are 5 pairs of gill slits.
The main feature of the fox shark is the tail fin. Its upper part is very long and corresponds to the length of the body. With the help of this powerful blade, a predatory fish stuns its prey. The pectoral fins are sickle-shaped. The dorsal fin is relatively high and is located approximately in the middle of the back. There is a tiny second dorsal fin. The pelvic fins are quite large. The skin is covered with protective placoid scales.
The color of the upper body varies from purple-brown to gray. The sides are bluish, the belly is white. In length, together with the tail fin, the fox shark reaches 5 meters and weighs 230 kg. The officially registered maximum length is 5.7 meters. The estimated maximum length can reach 6.5 meters. And the caught female turned out to be the heaviest. With a body length of 4.8 meters, she weighed 510 kg.
Reproduction and lifespan
This species is ovoviviparous. Pregnancy lasts 9 months. There are from 2 to 7 newborns in the litter. They appear from March to June. They reach 12-16 cm in length, weigh 5-6 kg and add 50 cm in length every year. Adult fox sharks grow by 10 cm per year. Sexual maturity in males occurs at a body length of 3-3.2 meters. Females mature at a length of 2.5-4.5 meters. In the wild, the fox shark lives 15-20 years. The maximum life expectancy reaches 50 years.
Behavior and nutrition
The main diet consists of schooling fish such as mackerel, herring, garfish, anchovies, squid and invertebrates are also eaten. Hunting for fish is carried out singly or in groups. Sharks with their long tails drive the victims into a dense pile and swallow them. In addition, common fox sharks can jam their prey with their tails. In this way they attack sea lions and sea birds. However, this happens when there are few fish. If there is a lot of it, then only it is eaten.
conservation status
At the beginning of the 21st century, this species received the status of vulnerable. They linked it to commercial overfishing. Representatives of the species value meat and fins. Vitamins are obtained from the liver, and the skin is dressed. Currently, fox sharks are protected by law. The catch of these cartilaginous fish has decreased, but poachers still cause some damage to this species.
Class - Cartilaginous fishes / subclass - Elasmobranchii fishes / Superorder - Sharks (Selach)
Storystudy
The largest sea fox (Alopias vulpinus), its size is 5.5-6 meters, can be found in coastal areas. The smallest pelagic fox shark (Alopias pelagicus) is about 3 meters in size and lives at depths away from the coast. The color is a beautiful dark blue with a whitish belly. It has flat wide pectoral fins. The eyes are larger than those of the common fox, but not the same as those of the big-eyed fox. The most "beautiful" big-eyed fox shark (Alopias superciliosus) has unnaturally large bulging eyes. And what unites all representatives of this family is the possession of a magnificent fox tail.
Spreading
These sharks can be found near California and in parts of the Indian and Pacific Oceans.
The pelagic fox shark (Alopias pelagicus) lives in the Pacific and Indian Oceans. It can also be found off the coast of China, Taiwan, Western Australia and many other countries. 
Externalview
Adult thresher sharks measure about 4.7 meters and weigh about 360 kilograms. Outwardly, these sharks stand out with huge eyes, which is typical for individuals that live in dark places.
Structural features
The fox shark has a very long upper lobe of the caudal fin, reaching the length of the entire body.
reproduction
Fox sharks are viviparous. Adult females are capable of giving birth to no more than two sharks. Newborn individuals measure about 1.5 meters. With a body length of about 4 meters, fox sharks reach sexual maturity.
Lifestyle
When hunting, this shark uses its long tail as its main weapon. Approaching a school of fish, the sea fox begins to circle around it, foaming the water with whip-like strokes of the caudal fin. Gradually, the circles become smaller and smaller, and the frightened fish gather in an increasingly compact group. It is then that the shark begins to greedily swallow its prey. A couple of sea foxes sometimes participate in such a hunt. In some cases, the sea fox acts like a flail with its tail fin, using it to stun its prey.
Nutrition
The main food of fox sharks is small fish and shellfish. Thresher shark (Alopias vulpinus) has a fairly long upper tail fin. It has dimensions commensurate with the size of the body of a shark. The fox shark hunts with its fin. She wedges herself into a flock of fish and begins to beat her tail in different directions, stunning the fish. She then slowly eats her prey. Large individuals often attack even dolphins.
population
Fortunately, it has no commercial value, does not like to settle on the coast, has a formidable weapon and large size - all this helps it a lot not to get into the Red Book.
fox shark and man
Fox sharks are completely harmless to humans, however, during the dive of divers, they revolve around him, although they do not attack. However, there is information that these individuals attacked boats.
The fox shark is the most interesting representative of the ocean depths. This is a large cartilaginous fish whose body shape resembles a torpedo. The genus includes predators of three species. All of them have characteristic signs of body structure and behavior.
What is the name associated with?
The genus of sharks got its unusual name due to the long tail, or rather, the tip of the caudal fin. The upper segment can be almost half of the entire length of the predator. In addition to size, the tail has another feature - the elongated tail is flexible and mobile. The British, having observed the hunting of a predator, gave him the most accurate name: thresher shark. Literally, it sounds like a "thresher shark." This is due to the extraordinary way of hunting.
Unusual hunting
The fox shark does not trade for trifles: it does not chase individual victims, but prefers a plentiful "restaurant" menu. During the hunt, the predator drives the frightened prey into a dense jamb, crashes into it and begins to “thresh” in different directions with its long tail. Then he slowly dines on stunned fish. Given the size of the predator, one can imagine the strength of such a "thresher". Fishermen who managed to catch an amazing shark complained that the fish pulled out of its usual environment onto the deck managed to smash and break everything it reached with its tail.
Appearance
Since the tail is the most prominent part of this species, descriptions of the appearance of a predator almost always begin with it. However, it is worth noting that the fox shark is the most impressive representative of cartilaginous fish. It has an elongated torpedo-shaped body, a broad head and a pointed muzzle. For breathing, the underwater inhabitant has 5 paired gill slits. Two extreme slots are located above the pectoral fins. The fins themselves are pointed and long. The fox shark has a small curved mouth with labial indentations. The teeth of the predator are small, and their edges are smooth.
The anal and dorsal fins are smaller than the tail fins. Different have slight differences in the size and color of the fins.
Systematics of species
The family of sea foxes is divided into 3 types:
- Alopias vulpinus, that is, the common sea fox.
- Alopias superciliosus is a deep-seated thresher shark called the bigeye fox.
- Alopias pelagicus, a species of pelagic (small-toothed) foxes.
In 1995, a fish was discovered in the waters of California, which they wanted to designate as the fourth species, but this theory was not confirmed, and the fourth species remained unrecognized.
Main differences. red fox
It has a streamlined body shape with a clear curve of the back. She has a cone-shaped short head with medium-sized eyes, devoid of a third eyelid. The predator's teeth are small, fang-like, slightly flattened. The average size of sharks is about five meters. At the same time, a maximum was recorded - more than 7 m, and a minimum - less than four.
Shark body color is heterogeneous. Individuals came across and dark brown, and blue-gray, and steel. Some fish had a black back and a light belly.
Deep Sea Bigeye Fox
Despite the body structure typical of fox sharks, this representative is easily recognizable by the size of the eyes. The big-eyed fox shark fully justifies its name. In some individuals, the diameter of the eye reaches 10 cm. The peculiarity of the location of the organ in the orbit allows the predator to see not only in front and on the sides, but also to survey the space above the head.
Another distinguishing feature of the species is the special lateral grooves. They are formed at the point of transition of the body to the head, pass over the gill slits and eye sockets.
The teeth of the bigeye fox shark are larger than those of other species. They have one apex and are the same size on the upper and lower jaws.
The body color is brown-violet, the belly is always lighter than the back. The dorsal fin is shifted towards the tail.
pelagic fox
The color is dark: most often these are various shades of blue and gray. The belly of the shark is much lighter.
The species has well developed pectoral, caudal and dorsal fins. But at the same time, the second dorsal and anal fins are very small. The elongated tail lobe is narrower than in other species.
Habitat and diet
The fox shark has a wide range. It is found in the tropics and temperate latitudes. The pelagic species is characterized by an existence remote from coastlines. This species lives in the surface layers and at depths up to 150 m.
The big-eyed fox prefers more serious depth. She is comfortable 500 meters below the surface.
They love the coastal zone, but they also feel good far from the land. This species prefers the surface layers, but can dive up to 500 meters.
Thresher sharks do not attack too large prey, since schooling fish are the basis of their diet. We have already spoken about the hunting habits of this genus, but this does not mean that predators cannot make exceptions. In the absence of fish schools, any living creature can be in the diet of the fox shark. A man, most likely, will simply be stunned by his tail - the shark will not dare to dine with such an unpredictable opponent.
frilled shark
The frilled shark (Chlamydoselachus anguineus) is the only deep-sea shark in its family. The maximum length is 2 m. It bears offspring for about three and a half years.
The frilled shark is a rare and unusual shark species. The maximum length is not more than two meters. The body of a shark is serpentine. The anal, dorsal and two ventral fins are closer to the tail. Which makes her look more like an eel than a shark. She hunts on the same principle as a snake. First, it bends and quickly straightens in a jerk. And these are not all its unique features. Up to three dozen rows of small and very sharp teeth will not release the victim. Even if she manages to escape, she will receive numerous lacerations. The frilled shark hunts for small cephalopods and small sharks. This shark, unlike its relatives, does not tear the victim to pieces, but absorbs it entirely. Capable of swallowing fish half the length of its body. It lives at a depth of up to 1.5 thousand meters, but most often it can be found at a depth of about 200 meters.
The frilled shark got its name for the skin folds around the head, of which there are 6 on each side. They were formed by gill fibers, which cover the gills. The shark is able to cover its gills to create pressure inside the mouth, which helps to swallow food. The average length of these sharks is about one and a half meters. The largest specimen that is known to science reached a length of 2 meters.
The frilled shark's pregnancy lasts 3.5 years. This is the longest pregnancy among all vertebrates known to science. In one month, the embryo grows an average of 1–1.5 cm. At three months, the embryo has a fully formed jaw, fins and external gills, but it will stay in the womb for more than 3 years. Newborns are about 50 cm long. The frilled shark gives birth to an average of 10–15 pups.
The frilled shark is not of particular value to humans, unlike other marine life. But often comes across in the nets of fishermen and goes to food. This shark is considered a rare species due to its small number. Does not save the species and deep-sea habitat.
Source
From
Pelagic megamouth shark
The pelagic megamouth shark (Megachasma pelagios) is the only species known to science today from the genus Megachasm. In addition, this is one of the three types of sharks whose diet includes plankton.
Science knows only three types of sharks that feed on plankton: giant whale sharks and pelagic largemouth sharks. The pelagic largemouth shark lives at different depths from 50 to 1,600 m. The species was discovered in 1976. Until now, it is the only instance of the family. According to 2014 data, only 60 individuals of this species were found. Habitat Atlantic, Pacific and Indian oceans.
The largest individual of the species was a female pelagic megamouth shark. Its length was 5.7 m. It got into fishing nets off the coast of Japan. Despite the fact that the female was released, she was later washed ashore already dead. Little is known about the life of these sharks. According to the structure of the teeth, which are quite small, awl-shaped and the study of the stomach of dead individuals, these sharks are filterers. Their diet includes krill and other small inhabitants of the oceans.
Since the body of this shark is rather weak, it leads a passive lifestyle. For hunting plankton, she has her own secrets. When the mouth opens, the upper jaw moves forward. Thus, opening the silvery edging of the mouth, which is a bait for plankton.
Source
From
Class: cartilaginous fish
order: carchariformes
family: gray sharks
genus: gray sharks
habitats
The gray reef shark is found almost throughout the Pacific and Indian Oceans, adhering to coral reefs, strong currents and depths up to 280 m.
Distinguishing properties
The average body length usually reaches 1.9–2 m, males are somewhat larger than females. The maximum mass of a gray shark caught is 33.7 kg. Color - various shades of gray, sometimes brownish and even bronze. The shape of the shark's body resembles a torpedo.
Lifestyle
This is a smart, cunning and fast animal with a phenomenal sense of smell and quick reactions, showing great interest in everything that moves. Gray sharks are active throughout the day, hunting mainly at night, gathering in small flocks of 5 to 20 individuals. Lives up to 25 years.
reproduction
During the mating season, gray reef sharks protect an individual area from other individuals of their species, the area of which is about 4 km2. When a competitor appears, the animal first shows dissatisfaction, making sharp movements with its tail and distinctly arching its back. The gray reef shark is a viviparous species. Once a year, the female gives birth to 1-6 cubs.
Food and Enemies
The main prey is fish, mollusks and crustaceans, the favorite is octopuses and other cephalopods. There are practically no natural enemies. Only angry individuals of their own species or humans are dangerous.
Source
From
Class: cartilaginous fish
order: carchariformes
family: gray sharks
genus: gray sharks
The Malagash night shark (Carcharhinus melanopterus) lives in the tropical waters of the Indian and Pacific Oceans. Through the Suez Canal, the species entered the Mediterranean Sea. Tries to stick to the coastal zone and shallow water.
Distinguishing properties
The average body length is 1.5–1.8 m, and the weight is 45 kg. The shape of the body is torpedo-shaped and streamlined, the head is slightly flattened. A distinctive feature of the species is the black end of the first dorsal fin.
The tip of the second dorsal and anal fins may also be black. The upper part of the body is grayish-brown, the bottom is white.
Lifestyle
Night predator. Prefers to stay in small groups, never forms large flocks.
There have been cases of attacks on people, but no deaths. Can easily exist in fresh or slightly brackish water. These large marine predators are tied to the same habitats. The average life expectancy is 30 years.
The basis of the predator's diet is fish, crustaceans and molluscs.
The main enemies of sharks are toothed whales.
reproduction
Sexual maturity occurs when the body size reaches 95–97 cm. The mating season lasts from November to March. During the courtship period, the male not only actively pursues the female, but also strikes her in the area of the fins, and the wounds completely heal only after 4–6 weeks. Pregnancy lasts according to various sources from 7 to 16 months. Shark is a viviparous fish. At the same time, 2–3 sharks 2–4 cm long are born. Cubs are born every two years. Babies grow quickly, adding up to 23 cm annually.
Source
From
Class: cartilaginous fish
squad: stingrays
family: diamond
genus: rhomboid rays
habitats
The sea fox, or spiny stingray, is most common along the eastern coast of the Atlantic Ocean. The expanses of water from Norway to Namibia are the places of accumulation of the world population of these rays. The species is found in the Mediterranean and Black Seas, off the coast of South Africa and Madagascar.
What does a sea fox look like?
The female sea fox can reach a length of 120 cm, the male is somewhat smaller - the maximum length of his body is 70 cm. The shape of the body resembles a rhombus. The upper side of the body of the sea fox is covered with numerous spines, it is rough and colored in brownish tones with a pattern of dark and light spots. The long and thin tail is also covered with spikes. The underside of the body is light and smooth. The color of the skin is variable - it strongly depends on the habitat of the stingray.
Lifestyle and nutrition
The main habitat of the species is the sea muddy bottom. Stingrays live at depths of 20–300 m and deeper. In summer they come quite close to the coastline, and in winter they migrate to the depths.
It feeds on benthic crustaceans, sometimes small fish.
The danger is represented by various predatory fish, however, stingrays are able to defend themselves and are perfectly adapted to survive in the aquatic environment.
reproduction
The sea fox, like other stingrays, reproduces by egg production. After mating, the female begins to lay eggs - up to 170 during the year. Each egg is enclosed in a dense protective capsule, which has special processes and threads on the sides, with the help of which the female attaches the eggs to the algae. In the corner of each egg there is a small hole for oxygen, so that the fry can breathe. After 5 months, miniature rays are born - each no more than 12 cm in length. Having reached 15–17 cm in length, a teenager is able to hunt on his own.
Source
Bigeye fox shark, or big-eyed sea fox, or bigeye fox shark, or deep sea fox(lat. Alopias superciliosus) - a species of cartilaginous fish of the genus fox sharks of the family of the same name of the order of lamniformes. It lives in all temperate and tropical waters of the Indian, Pacific and Atlantic oceans. It reaches 4.9 m. Bigeye fox sharks have an elongated upper lobe of the caudal fin, characteristic of fox sharks. The eyes are very large, up to 10 cm in diameter in adults. They have a streamlined body, a short and pointed snout. Their eyes are adapted to hunting in low light conditions. It is one of the few shark species that make diurnal vertical migrations. They spend the day at depth, and at night they rise to the surface to hunt.
Thresher sharks hunt using their long tail like a whip. They knock down the joint and stun their prey, this explains their English name. Thresher shark, which literally translates as "thresher shark". Reproduction occurs by placental live birth. There are 2 to 4 newborns in a litter. Embryos eat unfertilized eggs produced by the mother (oophagy).
Bigeye fox sharks are not dangerous to humans. Their meat and fins are highly valued and the species is commercially and sport fished. The low reproductive rate makes these sharks very susceptible to overfishing.
Taxonomy
|