Fish species of Russia
It is the largest fish found in fresh waters, since in some cases it reaches a length of several meters and a weight of up to 1120 1280 even, and in the old days more than 1600 kg.
In addition to size, the Beluga is easily distinguished from all other sturgeon species by its thick cylindrical body and short pointed nose, which is somewhat transparent, since it is not covered by scutellum ivory; her mouth is huge, takes up the entire width of the head and is surrounded by a thick lip; the whiskers are distinguishable by their width and grab to his mouth. In addition, the bone on the head and scutellum bugs, especially lateral and ventral, appear to be relatively little developed: the dorsal is mostly 12-13, 40-45 lateral and ventral 10-12. General body color ash gray, the abdomen is grayish-white, yellowish nose.
Caspian and Black seas with rivers flowing into them, are almost the only stay of this giant fresh water, which, thus, is exclusively our heritage. The Volga, Ural, Kura, don, Kuban – the main area of fishing and only Beluga in the Danube, it is still quite numerous. In fact, Beluga the greater part of his life spent at sea and in the river is the attainment of a known age for spawning that, as we will see later, happens not every year, and then returned back into the sea, as well as fry it. However she goes very far and there’s even some onomasiological that the more Beluga, the farther it goes to spawn. Occasionally Beluga comes from the Black sea to the Mediterranean and the Adriatic, and not so long ago (1850) was one caught in the vicinity of Venice.
As all young belugas do not occur in the rivers and since it is known that adult fish spawn in a year, which is, however, further, it is clear to us that the main weight of sturgeon at any time of year, especially in the winter, lives in the sea. From research Severtsev there is no doubt that winters in the Urals is not the red fish that spawn in the spring, but the one that spawned in the third year and rose in the river in late summer and early fall. With his usual insight, based on the fish, its size, degree of maturity of eggs, part on the testimony of the Ural Cossacks, our well-known biologist almost completely explained the periodic phenomena of life red fish in the waters of the Ural, where these phenomena are located in the most favorable conditions, so to speak, in the most natural setting. Thanks to him we know now that the majority of sturgeons, spikes, belugas, part of Serug included in the sea in the spring, the essence of specimens that have just reached sexual maturity; the fish are wintering in the river, in the so-called etawah, there are already more adult, which is included here from the sea, with the intention that with the opening of the river to rise above and to spawn.
Thus, in winters the river only a small portion of red fish, forced to spawn in the spring. Young fish have reached sexual maturity, as well as all small wintering in estuaries or in shallow depths of the sea; in the more deep, winters single fish returning from the rivers in late summer and early autumn; finally, at the greatest depths are home to old Beluga, already unable to reproduce. Very it is even possible that larger specimens of this fish out of the sea only once in several years: the rarity of very large sturgeons, and a large difference in their weight partly serve as evidence of this view. It is difficult to assume, for example, thirty Beluga could, if we assume that the first time she spawned on the tenth year, ten, but, considering it reverse, twenty times to avoid the hundreds of tackles and networks which are waiting in the river.