Pike

[1]Pike, or common pike[1] (Lat. Esox lucius), — fish of the familythe Shchukovs. It is distributed in fresh waters of Eurasia and North America. It usually lives in the coastal zone, in water thickets, in non-flowing or low-flowing waters. It can also occur in desalinated parts of the seas, for example inIn Finnish, Riga andCuronian LagoonOf the Baltic Sea, inTaganrog Bay The Sea of Azov. Pike can withstand the acidic reaction of water well, can live comfortably in reservoirs with a pH of 4.75. With a decrease in oxygen content to 3.0—2.0 mg/l, respiratory depression occurs, so inpike often dies in overseas reservoirs.

Content

1 Appearance of pike

2 Reproduction

3 Life cycle

4 Lifestyle

5 Meaning for a person

6 In cooking

7 In culture

8 Notes

9 Links

Appearance of pike

Length up to 1.5 meters, weight up to 35 kilograms (usually up to 1 meter and 8 kilograms). The body is torpedo-shaped, the head is large, the mouth is wide. The color varies depending on the environment: depending on the nature and degree of vegetation development, it can be gray-greenish, gray-yellowish, gray-brown, the back is darker, the sides with large brown or olive spots that form transverse stripes. Unpaired fins are yellowish-gray, brown with dark spots; paired fins are orange. It feeds mainly on fish. Silver pikes are found in some lakes.

Males and females can be distinguished by the shape of the genitourinary opening, which in males has the appearance of a narrow oblong slit, colored in the color of the womb, and in females — an oval depression surrounded by a pink roller.

The pike's body has an elongated, arrow-shaped shape. The head is very elongated, the lower jaw protrudes forward. The teeth on the lower jaw are of different sizes and serve to capture the victim. Teeth on other bones of the oral cavity are smaller, directed with sharp ends into the pharynx and can sink into the mucous membrane. Thanks to this, the prey easily passes, and if it tries to escape, the pharyngeal teeth rise and hold the victim.

Pikes are characterized by a change of teeth on the lower jaw: the inner surface of the jaw is covered with soft tissue, under it there are rows of 2-4 replacement teeth, which are adjacent to the back of each active tooth, forming a single group (dental family) with it. When a working tooth goes out of use, a neighboring replacement tooth of the same family becomes its base. At first, it is soft and unstable, but then it grows tightly with the base to the jaw bone and becomes stronger. Pike teeth do not change at the same time. At the same time, some tooth groups end at the edge of the jaw with an old tooth that is already resorbed, others with a strong working tooth, and others with a still mobile young one. In some reservoirs, the change of teeth in pike increases during certain seasons, and then the pike in these reservoirs stops taking large prey, since it can escape from the mouth of the predator. Catching it at this time is difficult, as it can not grab the nozzle.

Reproduction

In natural reservoirs, female pike begin to breed in the fourth, less often in the third year of life, and males — in the fifth.

Spawning pike fishing occurs at a temperature of 3-6 °C, immediately after the ice melts, near the shore at a depth of 0.5–1 m. During spawning, fish come out into shallow water and splash noisily. Usually, the smallest individuals come out to spawn first, and the largest ones come out last. At this time, pikes are kept in groups: 2-4 males in one female; near large females-up to 8 males. The female swims in front, the males swim behind her, about half a body behind. They either cling to the sides of the female, or try to stay directly above her back. From the water at this time, the dorsal fins and upper parts of the fish's back constantly appear.

During spawning, pikes rub against bushes, roots, stems of reeds and cattails, and other objects. Fish do not stay in one place for a long time, they move around the spawning ground all the time and spawn. At the end of spawning, all the individuals of the spawning group rush in different directions, causing a loud splash; the females often jump out of the water into the air.

One female pike, depending on the size, can lay from 17.5 to 215 thousand eggs. The eggs are large, about 3 mm in diameter, slightly sticky: they can stick to vegetation, but easily fall off when shaken off. After 2-3 days, the stickiness disappears, most of the eggs roll off the plants, and their further development occurs at the bottom.

Normal development of pike roe on the bottom in non-flowing water is possible only because in spring, at low temperatures, the water is relatively highly saturated with oxygen, and as the water warms up, the oxygen concentration in it quickly decreases. Thus, the earlier the pikes start spawning, the less eggs die.

If there is a rapid decline in water after pike spawning, this leads to mass death of eggs; this phenomenon is often observed in reservoirs where the water level is unstable.

Life cycle

Pike in a public aquarium (Kotka, Finland)

Depending on the water temperature, the development of eggs occurs within 8-14 days, the larvae that are hatched from it are 6.7—7.6 mm in length. As the residual bubble resolves, the larvae switch to feeding on external resources: small crustaceans-cyclops and daphnia. With a length of 12-15 mm, pikes can already hunt carp larvae. Spawning of cyprinid fish usually occurs after the spawning of pike, which provides nutrition for pike young growth. After reaching the size of 5 cm, the pike completely switches to feeding on fry of other fish, mainly carp. If a pike of this size is kept inIf the fish is kept in the aquarium and fed to small crustaceans, it will die, since the energy costs of extracting food are not compensated by the nutrients available in such production.

It happens that in the spring, pikes together with meltwater enter the floating lakes. After some time, the connection of these reservoirs with the river is interrupted, and the life of fry that have emerged from caviar in such conditions is very different from their life in the river or large permanent reservoirs. Due to the lack of food resources, pike growth here is extremely uneven: the length of fish of the same age may differ by 2-2. 5 times. Small individuals become prey to large ones, sometimes, with a significant shortage of food resources, pikes 3-4 cm long already resort to cannibalism.

Such degenerate food chains, consisting only of pikes (when fry feed on plankton, large pikes — fry, and they, in turn, feed on even larger ones), are observed on a permanent basis in a number of reservoirs. This happens in northern (usually tundra) lakesYakutia andCanada, where the amount of nutrients is extremely small, that is, not enough to maintain any complex food pyramid. In addition to scientific literature, such "pike lakes "are also described in fiction, for example, in the book"Canada Smelling of Tar" by the Polish writer Arkady Fiedler[2].

At the same time, despite the extremely simplified structure of the food chain, the ecosystems of such reservoirs have been in a stable state for centuries — in the bottom sediments and on the coast, researchers have not found any bone remains other than pike in such reservoirs; this is also confirmed by the folklore of local residents.

Lifestyle

In the pond, the pike is kept in thickets of aquatic vegetation. Usually it is motionless there and, hiding, suddenly rushes to the prey. Caught prey is almost always swallowed from the head — if the pike has grabbed it across the body, then, before swallowing, it quickly turns the prey head into the throat. In addition to the fangs, which the predator grabs and kills prey, on the palate, tongue and partly on the cheeks of the pike there are teeth-brushes that can bend and take a horizontal position, with their points towards the throat. These sharp brush teeth are necessary for the pike not only to hold the prey, but also to facilitate swallowing. When the victim tries to escape from the mouth, the pike's teeth with their sharp ends rest on it and do not allow it to slip out, pushing it further into the throat.

When attacking, the pike is guided by vision and the lateral line, the organs of which are developed not only on the midline of the body, but also on the head (mainly on the front of the lower jaw).

The basis of pike nutrition consists of representatives of various fish species, which include: roach, perch, ruff, bream, guster, minnow, char, minnow, goby-stonefish, etc.As described above, the pike does not disdain representatives of its own species. In spring and early summer, this predator willingly eats frogs and molting crayfish. Pikes have been known to grab and drag ducklings under the water, as well as mice, rats, waders and squirrels crossing rivers during their migrations. Large pikes can attack even an adult duck, especially during the molting period, when these birds do not rise out of the water into the air. Pike victims are often fish, the length and mass of which reach 50 %, and sometimes 65 % of the length and mass of the predator itself.

The diet of medium-sized pike-about half a meter long-is dominated by numerous and low-value fish, so pike is a necessary component of rational fisheries on lakes; its absence in lakes leads to a sharp increase in the number of small ruff and perch.

Meaning for a person

Pike in the hands of a fisherman, Drava River, Hungary

Pike is quite widely bred in pond farms.

Pike meat contains 1-3% fat and is a dietary product, especially if the fish comes to retail in live form.

The maximum age of pike in commercial fishing at the present time, as well as during the last few centuries, does not exceed 25 years. The catch of a 33-year-old pike is reliably documented. The stories about much older pikes found in popular literature should be classified as legends.

Among the stories of this type, the story of the "Heilbronn pike" is especially common, which was allegedly caught personally by Emperor Frederick II in October 1230, marked it with a gold ring and released into the lakeBeckingen Böckingen) near the town of Heilbronn, where this pike was caught 267 years later, in 1497. At the same time, it reached a length of 570 centimeters and weighed 140 kg. The spine of this pike was transferred for storage to the cathedral of the cityMannheim.

This story aroused the interest of a German natural philosopherLorenz Oken. He studied the historical chronicles in detail and found that Frederick II lived in Constantinople at that time.Italy on the islandSicily and therefore could not ring the pike in the territory in any wayGermany. It was also possible to examine the spine of a giant pike, displayed in the Mannheim Cathedral. It turned out that this is a fake and that it is composed of the vertebrae of several individual pikes.

No less amazing is the story of the " pike of the kingBoris Fyodorovich", which occurred in 1794, when during the cleaning of the Tsaritsyn ponds under theMoscow caught a pike with a ring on the gill cap. The inscription engraved on the ring read:"Tsar Boris Fyodorovich planted it." Since Boris Godunov ruled from 1598 to 1605, it means that the pike caught must have been about 200 years old. But today the veracity of this fact is disputed, as no documentary evidence has been preserved[3].

In cooking

Pike comes on sale in live, chilled, frozen and canned form. The meat is bony, sometimes smelling of ooze; dietary, as it contains about 18.4 % protein, 1.1-3 % fat[4]. Large and medium-sized pike are most often used chopped (for fish cutlets, meatballs) and stuffed, small (weighing about 200-300 g) are boiled inthe spic

y broth 1 kg of fish — 0.75 l of water, 1 corenew carrots, parsley, celery, 1 onion, 3 pea black and 1 pea allspice, 1 Bay leaf; boil all together for 5-7 minutes, then in the broth, put the fish and cook until done (about 20 minutes) on low heat, not allowing a strong boil, then take out the fish with a slotted spoon, spread on a heated dish, sprinkle with parsley and serve with boiled potatoes and butter. Small pike can also be fried or used for fish soup. The British in the middle of the XX century pike was considered the most delicious and expensive fish. In some countries, and to this day, pike dishes are considered delicacies.