Atlantic atlantic. Acipenser Sturio) is a chord animal, belongs to the class of radiant, sturgeon family. Occupies a special place in the detachment. The presence of phylogenetic connections with other species is still in question. Scientists are engaged in the establishment of accurate taxonomic status for part of the population, which was in geographical isolation. We are talking about the North American form of Atlantic sturgeons.
Description
The Atlantic Domestic was adapted to live, both in the sea and in the fresh pond, which they need during the propagation. Reaches a giant size, 6-7 m. As a rule, individuals weigh from 100 to 200 kg. A case was recorded when a giant with a maximum weight of about 1 ton was caught.
The following sturgeon representatives are distinguished:
Appearance
Has an oblong body shape, the head is pointed forward. With the help of an enlarged rear tail fin can move quickly in water, which helps when hunting. He does not have folds formed by gills. The body is covered with rhombic bone plates. Small mouth, lower lip interrupted, head is narrowed to the front, added.
Eye size is small, rainbow shell of gold. For hunting, the insight is not used at all the organs of vision, but four cylindrical antennae located on the head. They serve the smell organs.
It has a dim color. Usually olive-blue, golden color. The abdomen is painted white.
Lifestyle
Lives in coastal sea waters. Deepsea sections a habitat where it feeds on the bottom mollusks and various crustaceans. Lives a long life, about 100 years. Males reach puberty at the age of 10-11 years, females become sexually mature in the age of 18. To multiply, sturgeons need to rise 100-250 km upstream of the river, for spawning grounds. These are river areas with pebble soil at the bottom, with a quick flow.
Young individuals live long enough in the rivers, up to 3 years. They move to sea when body length reaches 50-60 cm.
Spreading
Almost disappeared in the wild. Was previously distributed along the entire coast of Europe. He lived the basins of the Baltic and North Sea. Today you can still find an Atlantic sturgeon in the Black Sea, in the southeast and in the Rioni River. Lives in the North Atlantic and the Mediterranean Sea.
Food
Favorite food bottom invertebrates. Young sturgeon is worms, mollusks, crustaceans, an adult is hunting for small fish, hamsa, anchovyuses.
Sturgeon larvae feed on planktonic crustaceans and cheeromides, eat insect larvae for food. Continues to eat in winter. To catch up, long distances swim.
How propagates
By the age of 7-15, individuals become sex. In this case, the body length, as a rule, reaches 1 meter. Starting in spring, Atlantic is a spawning, it overcomes many kilometers through the fast flow of rivers. During the propagation, the frozen is about 5 million. larvae. Caviar is glued to stones or soil, then the development of eggs lasts up to 2 weeks. The resulting fish returns back to the sea.
Providence
Sturgeon caviar and its meat are a large delicacy, it is expensive. The number is noticeably reduced in view of poaching, as well as pollution of its habitat. The Atlantic Pister is listed in the Red Book. Its number under the threat of disappearance. Poachers carry out sturgeon catching using gill nets during spawning migration.
Currently, scientists are developing the process of cryoconservation of the genome so that in the future it is possible to recreate the form and engage in breeding not only in artificial conditions, but also in the wild.
Listed in the Red Book of Eurasia
Is part of the main fishing objects. Due to large sizes and taste, it is considered significant prey. A significant increase in the catch occurred by improving the equipment for fishing. The number of species has significantly declined, and at the moment has reached a critical value. The destruction of part of the reservoirs used by Atlantic sturgeons for propagation was caused by the construction of dams and dams. And due to the constant discharge of wastewater and production waste into river reservoirs, sturgeons ceased to exist in wild conditions.
Interesting Facts
- During excavations of ancient human settlements created more than three thousand. years ago, the bones of the Atlantic sturgeon were found. According to the available fragments, scientists found that some copies of more than a hundred years.
- Among the fishermen, the Atlantic sturgeon due to its size is respected and popular.
- In 1909, a fish was caught in the North Sea, the length of which was three and a half meters, and weight more than 300 kg. In 1851, the case of a female catch, weighing more than 200 kg, was recorded in the Neva River. There were about 80 kilograms of black caviar in her stomach.
- A wellknown place for breeding sturgeon is the small pool of the Gironda River, in France. A special lady for fishing was built. Scientists expect an increase in the population when females become sex.
