In our article we want to talk about the famous predator - the herring shark. Have you ever heard of such a thing? She has a lot of names, among which - a blue dog, a llama, a bottlenose, a mackerel, a mackerel shark, a guinea pig, etc.
Herring atlantic shark
This shark belongs to the family of herring sharks of the order Lamiform and has a characteristic appearance for this species.
All predators of this order have five branchial fissures, dorsal and anal fins. They are armed with very sharp teeth, but they have no blinking membrane. These are the structural features of the herring shark. The appearance of the Atlantic shark is quite ordinary for the representatives of this family. The body is quite thick, spindle-shaped, a crescent-shaped caudal fin, and a sharp, conical snout.
The upper part of the body has a bluish-gray color (from light to the darkest shade), but the peritoneum is very light, almost white. There are no spots or streaks on the body.
The eyes are large. The teeth are large enough, triangular in shape, and in adult sharks at the base of each tooth, a couple more small on both sides grow. Imagine up to sixty teeth on each jaw.
A shark lives from twenty five to thirty years.
Atlantic herring shark reaches a fairly large size. There are facts about the existence of specimens up to 3.7 m in length with a weight of up to two hundred and thirty kilograms. However, the usual average size of a predator is from one and a half to two meters, while its weight is about one hundred kilograms.
How does an Atlantic shark live?
Herring shark lifestyle is no different from the behavior of other representatives of this genus. She is constantly in motion throughout her life, sometimes resting at the bottom. The shark does not have a swimming bladder, which means that it does not have the buoyancy that ordinary fish have. This fact makes her move continuously, otherwise she will simply drown.
Even a dead herring shark never rises to the surface, it finds refuge at the bottom or becomes the prey of scavengers. In addition, she knows how to maintain the desired temperature of her body, which is higher than the temperature of sea water. How does she do it? The herring shark has its own mechanism of thermoregulation. Everything is quite simple. Blood in the muscles circulates through special heat exchangers, where it heats up. Thus, the shark raises body temperature by seven to ten degrees. Such an amazing property helps predators quickly adapt to cold water and makes it possible to move faster in pursuit of prey.
Where do herring sharks live?
The Atlantic herring shark lives in the vast expanses of water that extend from the Western Atlantic to Argentina with Brazil. The habitat is wide enough. In the east of the Atlantic, the shark is found both in Iceland and in South Africa. Sometimes it can be seen in the Mediterranean Sea.
The Atlantic shark knows how to adapt well, and therefore it feels equally comfortable both in the open water and in the coastal waters of the islands and continents. For her, not very warm waters with a temperature of not more than twenty degrees are more preferable.
What does the Atlantic predator eat?
The basis of the diet of the shark is herring, and therefore fishermen believe that if you need a herring shark, then you must first find a school of fish. The predator lives at a depth of 700-800 meters from the surface of the sea.
Her diet includes sardines, tuna, herring, mackerel. Also, he does not neglect bottom fish: squid, flounder, stingrays, crustaceans and small sharks. The Atlantic shark is a very active and agile predator. Often these fish gather in small flocks of ten to fifteen individuals, cruising near the sea surface, exhibiting dorsal and caudal fins.
Such a flocking habitat gives them the opportunity to hunt effectively, surrounding schools of fish, they drive them to the center, in a tight circle, and then start a meal. They attack the victim with lightning speed, devouring it eagerly.
Sometimes sharks even attack fishing nets. They are incredibly stunned by the sight of a large number of fish caught by fishermen, then they bite through the nets, and the fish rush out, right into the mouth of greedy predators. Once in the belly of one such shark, fifty-seven small fish ranging in size from fifteen to twenty centimeters were found. Impressive, isn't it?
Breeding atlantic shark
Herring sharks are a genus of ovoviviparous predators. Fertilized eggs remain inside the fish until the birth of the offspring. The embryo is surrounded by a temporary membrane, which gradually disappears, and it begins to feed due to maternal secretion. I must say that developing embryos during this period eat nearby unfertilized eggs. Pregnancy lasts eight to nine months. And in the summer, sufficiently formed young individuals are born. Moreover, their length is from fifty to seventy centimeters. Each predator at a time is able to bring from two to five babies.
Industrial herring shark fishing
The herring shark (photo is given in the article) is not just a predator. Oddly enough, but it is an object of industrial fishing in many countries: Canada, USA, Norway, Ireland, Great Britain.
It turns out that the meat of a thunderstorm of the seas is quite tasty, although with an unpleasant specific smell. However, with proper preparation, this defect is very easily eliminated. Especially valuable are the fins, fat, liver and, of course, the skin. All parts of the fish that are unsuitable for food, haberdashery or medicine are sent for the manufacture of fishmeal.
Is a shark dangerous to humans?
The Atlantic shark is fast and dangerous to humans. However, there is no reliable information about her attack on people. Currently, several cases of bites by a predator have been reported. Therefore, it is difficult to talk about the degree of its danger. But in any case, it is better to be as far away as possible from such a predator, because it is not just that one of its names in antiquity came from the Greek expression "monster-cannibal". Thanks to industrial fishing, it’s not so easy to meet the Atlantic shark. It is practically absent in the Mediterranean Sea, and more recently, it was quite a lot. Therefore, it is taken under the protection of all-seeing ecologists as an individual that is on the verge of extinction.
Pacific shark
The Pacific herring shark is the closest relative of the Atlantic, from which it differs externally with a wide and short snout, as well as characteristic spots on the belly. In all other respects, these predators are quite similar, although they live in completely different places. Salmon variety is found only in the North Pacific Ocean.
The streamlined body is gray-blue in color. The head of a shark is large, but shorter than that of its relative. This makes her look like a small white shark. Here is such an unusual Pacific herring shark. The structural features of her are such that she also knows how to maintain the desired temperature of her body, which gives her the opportunity to dwell in cool waters and be faster and more energetic.
Sizes of the Pacific Shark
The Pacific shark reaches a fairly decent size. According to unofficial data, the length of her body is 4.3 meters, and the documented value is slightly more modest - 3.7 meters. And the weight reaches 454 kg. These are quite serious parameters for a predator. Females are usually larger than males. An interesting fact is that in different regions of habitat, there is a difference in the size of individuals. Moreover, females predominate in the east of the Pacific Ocean, but males predominate in the west. The reason for this phenomenon is unknown. Females live up to thirty years, and males live up to twenty.
Pacific Shark Habitat
The Pacific shark is found off the coast of Korea, Japan, in the Bering and Okhotsk seas, in the waters of the United States, its presence is recorded off the coast of Mexico and California. An interesting fact is that the Pacific herring shark, whose lifestyle is directly related to waters rich in food, does not sink to great depths. Below 500 meters from the surface of the sea you will never find it.
What is food for Pacific predators?
Sharks feed on medium-sized fish: mackerel, herring, chum salmon, salmon, pink salmon. Bottom fish is also present in their diet. In addition, the predator can afford to attack floating birds. Gathering in flocks of twenty to thirty individuals, sharks organize a collective hunt. The predator is so fast and mobile that sometimes it even makes migratory transitions for potential food.
Pacific sharks breed almost in the same way as the Atlantic sharks.
It is believed that this species is dangerous to humans, although the documents do not confirm the facts of the attack. Nevertheless, predators are very large and aggressive, and therefore, care should be taken in the regions where they live.
Some sources report shark attacks on divers, but such data has not been verified or confirmed. Moreover, this species is easy to confuse with others, and therefore there could be an error regarding the variety of the attacking predator.
Is the meat of the Pacific predator edible?
Shark meat is considered delicious, and in some countries, such as Japan, and in the regions of East Asia, this is generally a delicacy. However, this species of sharks is not involved in industrial fishing. Rather, it happens by chance when fishing for salmon. However, the Pacific shark is of interest for sport fishing, especially since its number is quite large. However, environmentalists are worried that in the future she did not expect the fate of an Atlantic shark, which is threatened with extinction.
In Alaska, industrial fishing was banned back in 1997, and sport fishing is also strictly controlled. Each fisherman is allowed to catch only two individuals per year.
These amazing creatures are these sharks. On the one hand, they are formidable predators dangerous to humans, and on the other hand, they are on the verge of extinction at the hands of all the same people. And it is not clear who should beware whom more. Although any predator in the wild is certainly dangerous to humans, you never know what to expect from him.