Mackerel combines useful qualities for humans: it is tasty, lives crowded and reproduces well. This allows you to catch it annually in huge quantities, and at the same time not damage the population: unlike many other types of fish that suffer from moderate fishing, mackerel is even very active.
View origin and description
The ancestors of fish appeared a very long time ago – over 500 million years ago. The very first authentically established is pikaya, a creature 2-3 centimeters in size that looks more like a worm than a fish. Pikaya had no fins, and she swam, bending her body. And only after a long evolution did the first species resembling modern ones appear.
This happened by the beginning of the Triassic period, at the same time the class of ray-finned animals arose, to which the mackerel belongs. Although the most ancient of the ray-finned animals are also very different from modern ones, the basics of their biology have remained the same. And yet, the ray-finned fish of the Mesozoic era almost all died out, and those species that inhabit the planet now arose already in the Paleogene era.
After the extinction that occurred on the border of the Mesozoic and Paleozoic, about 66 million years ago, the evolution of fish went much faster – like many other orders. Speciation went much more actively, because it was the fish that began to dominate in the reservoirs, suffering from extinction less than other aquatic animals. It was then, at the very beginning of the new era, that the first representatives of the mackerel family appeared: the later extinct Landanichthys and Sphyraenodus, as well as the genus of bonito that has survived to this day. The most ancient finds of these fish are more than 65 million years old.
Mackerels themselves appeared a little later, by the beginning of the Eocene, that is, about 55 million years ago, at the same time, most of the other genera belonging to the mackerel family formed, and its real flowering began, which continues to this day. The period of the most active speciation ended just then, but individual species and even genera continued to appear in subsequent epochs.
The genus mackerel was described by K. Linnaeus in 1758, received the name Scomber. It is noteworthy that the family to which it belongs (mackerels) and even the detachment (mackerels) was named after this fish. From the point of view of taxonomy, this is not entirely true, because mackerels were far from the first even in the family, but this genus is the most famous.
Appearance and features
The average length of this fish is 30-40 cm, maximum 58-63 cm. The weight of an adult is on average 1-1.5 kg. Her body is elongated, in the form of a spindle. The snout is pointed. The easiest way to recognize it is by the characteristic dark stripes on the back, despite the fact that the belly does not have them – the transition from striped to monochromatic colors in the middle of the body of the fish is very sharp.
The back of the mackerel is dark blue with a steel sheen, and the sides and belly are silvery with a yellowish tint. As a result, when the mackerel is shown near the surface, it is difficult for birds to see it, because it merges with the water in color; on the other hand, it is hardly noticeable to fish swimming below, because for them it merges with the color of the sky, as it is seen through the water column.
The mackerel has well-developed fins, and it has additional fins that allow it to swim faster and better maneuver. All species except the Atlantic have a swim bladder: in combination with a streamlined body and developed muscles, this allows it to swim at a higher speed than other species can reach, up to 80 km/h.
It reaches this speed in a sharp throw in just two seconds, which is comparable to the acceleration of the fastest cars, but it can also hold it in a matter of seconds. Usually all types of mackerel swim at a speed of 20-30 km/h, in this mode they can spend most of the day and not be exhausted – but for this you need to eat a lot.
Mackerel teeth are small, they do not allow hunting large prey: it is very difficult to tear tissue with them, they can only gnaw through very weak scales and soft tissues of small fish.
Interesting fact: When a large shoal of mackerel rises to the very surface of the water, then due to the movement of these fish there is a rumble that can be heard even at a distance of more than a kilometer.
Photo: Mackerel fish
Each species of this fish have their own range, although they partially overlap:
- Atlantic mackerel is found in the northern Atlantic, and is also found in the Mediterranean Sea. In warm weather, it can reach the White Sea, and most of all in the North;
- African mackerel also lives in the Atlantic, but to the south, their ranges intersect, starting from the Bay of Biscay. It can also be found in the Canary Islands and the southern half of the Black Sea. It is most common in the Mediterranean Sea, especially in its southern part. Juveniles are found as far as the Congo, but adults swim north;
- Japanese mackerel lives off the east coast of Asia and around Japan, the islands of Indonesia, east it can be found as far as Hawaii;
- Australian mackerel is found off the coast of Australia, as well as New Guinea, the Philippines, Hainan and Taiwan, Japan, to the north they are distributed up to the Kuril Islands. It can also be found far from the main range: in the Red Sea, the Aden and Persian Gulfs. Although this species is also fished, it is valued below Japanese.
As you can see, mackerel lives mainly in waters of moderate temperature: there are few of them and too far to the north, in the seas of the Arctic Ocean, and in too hot tropical ones. At the same time, nevertheless, the warmth of the waters of the seas in which it lives varies greatly. The point here is seasonal migrations: it moves to places where the water is at the optimum temperature (10-18 ° C).
Only the fish inhabiting the Indian Ocean practically do not migrate: there the water temperature changes little during the year, and therefore there is no need for migration. Some populations migrate over quite long distances, for example, the Black Sea mackerel swims to the North Atlantic in winter – thanks to warm currents, the water there remains in the optimal range. When spring comes, she makes her way back.
Now you know where mackerel is found. Let's see what this fish eats.
What does mackerel eat?
The menu of this fish includes:
- small fish;
- larvae and eggs.
While the mackerel is small, it mainly consumes plankton: it filters the water and eats various small crustaceans that are in it. It also feeds on small crabs, larvae, insects and similar small living creatures, without making much difference between them.
But it can also be engaged in predation: to hunt for various kinds of small fish. Most often from fish it feeds on young individuals of herring or sprat. Such a menu is more typical for already adult fish, and in shoals it can even attack very large prey.
A large school of mackerel can also hunt immediately for flocks of other fish that are trying to escape by moving to the very surface of the water . Then confusion usually begins: the mackerels themselves hunt small fish, birds dive at them, dolphins and other large predators swim up to the noise.
Mackerel fry often eat their own relatives. Although cannibalism is also common in adults: the largest fish often eat juveniles. All mackerels have a good appetite, but the Australian one is better than others, this fish is known for sometimes throwing itself even on a bare hook, it is so prone to devour everything indiscriminately.
Interesting fact: Mackerel can be fished, but not so easy because of its ability to sharp and strong jerks. It can get off the hook, it’s worth a little gape – that’s why fans of sport fishing love it. But it will not work to catch it from the shore, it must be done from a boat, and it is best to move away from the shore properly.
Active during the daytime and at dusk, resting at night. When hunting for other fish, they make a sudden throw, most often from an ambush. During such short throws, they can reach very high speed, so it is very difficult to get away from them.
The fish is pelagic, that is, it usually lives at shallow depths. Lives in shoals, and sometimes mixed: in addition to the mackerels themselves, it may include sardines and some other fish. They tend to hunt both in packs and singly. When hunting together, shoals of small fish often rise to the surface, where mackerels continue to chase them.
As a result, other aquatic predators interested in what is happening, and birds, primarily gulls, come into play – so some mackerels from hunters turn into prey because they lose their guard when trying to catch other fish.
But all this applies to the warm period of the year. For several winter months, mackerel completely changes its lifestyle and falls into a kind of hibernation. Although this cannot be called a full-fledged hibernation, the fish gather in large groups in wintering pits, and remain motionless for a long time – and therefore do not eat anything.
Mackerel lives for quite a long time – 15-18 years, sometimes 22- 23 years old. It grows more and more slowly with age, the best age for catching is considered to be 10-12 years old – by this time it reaches a fairly large size, and the meat becomes the most delicious.
Social structure and reproduction
Mackerels live in shoals, both from fish of the same species, and mixed, most often with herring, which is why they are usually caught together. Fish of the same size are strayed into shoals, very rarely large fish of 10-15 years old, and very young ones, turn out to be in them. It spawns from the second year, after which it does it annually. The first to spawn are the most adult mackerel, which have reached 10-15 years, in the Atlantic population this occurs in April. Then gradually younger individuals go to spawn, and so on until the last weeks of June, when fish at the age of 1-2 years old spawn.
Due to the annual breeding and the large number of eggs spawned at a time (approximately 500,000 eggs per individual), mackerel breeds very quickly, and even despite the large number of threats and industrial fishing, there are a lot of them. For spawning, the fish goes to warm waters near the coast, but at the same time chooses a place deeper and lays eggs at a depth of 150-200 m. This provides protection from many eaters of eggs, including other fish that do not swim so deep.
The eggs are small, about a millimeter in diameter, but in addition to the embryo, each one also has a drop of fat, which it can feed on at first. After the mackerel spawns, it swims away, while the eggs need to lie for 10-20 days in order for the larva to form. The exact period depends on the parameters of the water, primarily its temperature, which is why the mackerel tries to choose a warmer place for spawning.
Only the larva that was born is both defenseless against predators and very aggressive itself. She attacks everything that is smaller and seems weaker, and devours prey if she managed to overcome her – her appetite is simply extraordinary. They also eat their own kind. When it appears in length, the larva is only 3 mm, but, actively feeding, it begins to grow very quickly. Since there is not enough food for everyone, most of them die during this period, but the rest grow up to 4-5 cm by autumn – however, they still remain quite small and defenseless.
After this, the period of most active growth passes, the fish become less bloodthirsty, and their behavior more and more begins to resemble adults. But even when mackerels become sexually mature, they are still small in size and continue to grow.
Natural enemies of mackerels
A lot of predatory fish and other marine animals prey on mackerel.
- sea lions.
Despite being a fast swimmer, these large predators are difficult for her to escape from simply because of their size difference. Therefore, when such large fish attack, the flock can only rush in different directions. At the same time, each individual can only count on the fact that the predator will not go after it.
At the same time, the predators themselves can attack in groups at once, and then the school of mackerel suffers very much, for one such attack it can be reduced by a quarter. But in mixed schools, other fish are usually more at risk, because mackerels are faster and more maneuverable.
When the fish is at the very surface of the water, they begin to be threatened by attacks from large birds and marine mammals. Especially love her sea lions and pelicans. Even having had enough of other prey, they often wait for mackerel, because its fatty meat is a delicacy for them.
Interesting fact: When buying frozen mackerel, it is important to pay attention to several signs by which you can understand that it has been stored correctly and is not expired. Mackerel should be shiny and firm, with no wrinkled areas on the skin – this indicates that it has not been thawed before.
The meat should be creamy. If it is too pale or yellowish, the fish was caught too long ago or thawed during storage or transport. A large amount of ice indicates improper storage, so the meat is likely to be loose.
Population and species status
The status of the mackerel genus does not cause concern, as well as each species included in it. These fish multiply rapidly and occupy a vast range, therefore a very large number of them are found in the waters of the world's oceans. The highest density is observed off the coast of Europe and Japan.
Active fishing is carried out, because the meat is highly valued, it is characterized by a high degree of fat content (about 15%) and a large amount of vitamin B12, as well as other vitamins and microelements. It is also important that there are no small bones in it. This fish has long become one of the most famous in Europe and Russia.
It is also popular in Japan, where it is also actively caught, and besides, it is bred – thanks to effective reproduction, it is profitable to do this even despite the relatively slow growth. However, it noticeably accelerates under conditions of artificial breeding, but its minus is that the fish does not grow to the same size as in the natural environment.
They catch mackerel with gear, nets, seines, trawls. Often it is mined in wintering pits, where it is very crowded. But even despite active hunting, there is no decrease in the mackerel population, it remains stable, or even grows at all – for example, in recent decades it has been noted that it has become more common in the Pacific Ocean.
As a medium-sized predator, mackerel firmly occupies a place in the food chain: it eats small fish and other living creatures, and larger predators feed on it itself. For many, this fish is among the main prey, and without it, life would be much more difficult for them. People are no exception, they are also very active in catching and consuming this fish.