Nistru | Facts & Information

Origin

The distribution area is located in the Caspian Sea, The Black Sea and the Sea of Azov and on the tributary rivers, but due to the construction of dams, breeding is currently endangered.

In addition to the intensive construction of dams, overfishing and industrial pollution have caused the breeding and breeding habitat to be endangered, reaching that, at the level of 1990, about 30% of the population of sturgeon in the Caspian Sea and the entire population of the Azov Sea to be replaced by specimens bred and bred in captivity.

Among the countries involved in this repopulation program are Azerbaijan, Bulgaria and Iran, since 1995. The Sturgeon (acipenser gueldenstaedtii) is intensively bred in captivity for international trade and, until now, the official statistics regarding caviar Trading do not reflect the reality on the ground.

Nistru Food

They feed mainly on mollusks and crustaceans (shrimp and crabs) and sometimes fish such as Engraulis encrasicolus, Sprattus sprattus and gobiids. The main food of Sturgeon chicks (acipenser gueldenstaedtii) is represented by crustaceans.

Features Of The Sturgeon

The catch of Sturgeon decreased from 21,550 tons in 1977 to less than 1000 tons in 1999, and in the Danube Delta decreased from 24 tons in 1950 to less than 11 tons in 1999 and not necessarily due to efforts to reduce overfishing, but mainly due to the danger of complete extinction of the sturgeon species, at least in the Black Sea.

In 1998, the export of sturgeon caviar (acipenser gueldenstaedtii) amounted to 95.3 tons, of which 46 tons from Russia and 40 tons from Iran, the two countries being the main exporters.

This amount of caviar involves the capture of 1,361-1,588 tons of male and female sturgeon, using a standard rate of 6-7% of the body weight represented by caviar. At the level of 2000, the export of caviar decreased from 119.5 tons in 1999 to 95.9 tons, increasing, instead, the actual export of meat, from 53.5 tons to 204 tons.

The sturgeon species is now very rare in the Black Sea basin, where most breeding areas have been lost due to dams, the only place where there are a few rare specimens is in the Lower Danube area. The Caspian Sea basin has also lost about 70% of its breeding areas, due to hydroelectric power plants and dams on the Don River.

The native sturgeon population (Acipenser gueldenstaedtii) is in a decline of 90% since the last three generations (estimated at about 45 years), a phenomenon that is based on the reduction of 88.5% of the world catch in the last 15 years. This decline is increasing due to illegal fishing in the seas and oceans to obtain caviar, which will lead to the complete disappearance of the natural wild population. In the not very distant future, the survival of the species will depend entirely on restocking programs, which, however, advance with very small steps.

Aquaculture is the one that contributed to the accidental and intentional introduction of this species throughout Europe, but it is known to belong to the Caspian Sea, where it breeds in the Ural and Volga rivers and in the Black Sea, where the species is already in decline.

Unfortunately, in the Azov Sea, there is currently no native population to ensure the perpetuation of the sturgeon species (acipenser gueldenstaedtii), but only a few newly introduced specimens from captivity.

Breeding Sturgeon

As countries of origin, the Sturgeon is native to Azerbaijan, Bulgaria, Georgia, Iran, Kazakhstan, Moldova, Romania, Russia, Serbia, Turkey, Turkmenistan and Ukraine and has completely disappeared from Austria, Croatia and Hungary.

In the sea, sturgeons develop in shallow waters of the continental part, and in rivers they remain at depths between 2 and 30 meters. Larvae are found at considerable depths and in fast currents.

The vast majority of males begin breeding around the age of 11 to 13, while females around the age of 12 to 16. On the Volga River, males need 2 to 3 years of break to be able to reproduce again, while females need 4 to 5 years.

The breeding season begins in early spring, reaches its peak in the summer period and ceases with the autumn period. Preferred breeding areas are those where gravel predominates and Stony areas located at depths between 4 and 25 meters, and the water temperature must be between 9 and 12 degrees Cesius, for the habitat to be perfectly balanced.

Awareness of the extinction phenomenon of the Sturgeon (acipenser gueldenstaedtii) will lead, perhaps, in a not very distant future, to the stimulation of captive breeding programs of this ancestral species in imminent danger.