Some 100 years ago, fabulous fish by modern standards were caught in the Volga: weighing up to 1.2-1.5 tons and more than 4 meters long. And these are not fishermen's tales at all, but confirmed scientific facts. These were huge belugas, which have not been seen in the Volga for a long time, and the few representatives of this species that have remained in our days bear little resemblance to their great ancestors.
But what happened to the largest freshwater fish on the planet? Why did it almost disappear, and those few individuals that remained, with their modest size do not at all resemble the largest freshwater fish on the planet?
Belugas belong to the sturgeon family and live in the basin of the Caspian, Black and Azov seas. This fish belongs to anadromous species that live in the seas, but go into rivers to reproduce. The population of the Caspian beluga spawns in the Volga, Ural, Kura, Terek, and the Azov beluga spawns in the Don River. The Black Sea beluga lives off the coast of Ukraine, Bulgaria and Romania, therefore it spawns in the Danube, Dnieper and Dniester. Back in the middle of the last century, the beluga population lived off the coast of Italy in the Adriatic Sea, but today this species of sturgeon is not found there.
Belugas are predatory fish that feed on small aquatic organisms, molluscs, larvae and crustaceans at a young age, and when they reach a respectable age and size, they switch to larger prey - river fish. Belugas are real long-livers, as they can live up to 100 years. But this is not the only record for these fish. The fact is that belugas grow all their lives, that is, by the size of the fish, you can roughly determine its age. Well, the famous 4-meter specimen of the beluga, which was caught at the beginning of the last century in the Volga, most likely was close to its centenary.
But 4-meter giants are records of bygone days, in our time there are no such belugas. Those belugas that today swim in the waters of the Caspian and the Black Sea are extremely small in number, despite the fact that the species is listed in all the Red Data Books possible. Several factors led to such a deplorable situation, but the main culprit in such a plight of the beluga, of course, is a person.
Intensive fishing and pollution of river and sea waters led to a catastrophic population decline in the 20th century. The situation was worsened by the construction of numerous hydroelectric power plants on the largest rivers in Europe, which were not equipped with fish-passing mechanisms, which did not allow fish to go upstream to their usual spawning grounds. Volga, Kama, Kura, Don, Dnieper and Dniester - all of them were blocked by dams of hydroelectric power plants, which deprived beluga whales of most of their spawning grounds.
Another important feature that influenced the sharp decline in the population is the very long maturation period of the beluga. It takes a very long time for the beluga to reach reproductive age. Males of the Caspian beluga are capable of breeding no earlier than 13-18 years old, and for females this figure reaches 16-25 years. Thus, in order for the beluga to grow up and be able to leave offspring, a very long time must pass.
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The fact that the beluga needs to be saved, especially the population of the Sea of Azov, which is in a more deplorable state compared to the Caspian beluga, became clear back in the middle of the 20th century. They began to breed beluga in special nurseries, release eggs and fry into the Sea of Azov. This allowed to stabilize the situation a little, but the volumes released were not enough to maintain and increase the population size.
The current state of the species is of serious concern to ichthyologists. The weight of most of the belugas caught over the past 20-30 years does not exceed 300 kilograms, and the age of these fish is no more than 40-50 years. If in the middle of the XX century in the Volga there were about 25 thousand belugas going for spawning, then at the beginning of the XXI century their number did not exceed 5 thousand. It remains to be hoped that ecologists and fish farming specialists will be able to preserve this amazing species of fish and belugas of incredible size will again be found in the Volga.
In "Research on the state of fishing in Russia" 1861 reports on a beluga caught in 1827 in the lower reaches of the Volga, which weighed 1.5 tons (90 poods).
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