Conservation of the Sturgeon Fish in Lower Volga

Abstract

The river Volga is the largest in Europe. Its length is about 3600 km. The difference in height between the source and the mouth is 256 m. The mid-annual drainage is about 250 km(3); water flow is more than 7000 m(3)/s; during spring high water it is 26,000-28,000 m(3)/s. The basic supply to the Volga is provided by snow (60% of annual drainage), ground (30%) and rain (10%) water. In midsummer (July) the temperature of the water in the river reaches 23-25 degrees C. Eight hydroelectric power stations and a water-divider have been erected on the Volga. On the Lower Volga, fishery is traditionally well developed. About 70 species of fish. including six species of sturgeon, are found. All the sturgeon fish, except the sterlet, are diadromous. Nowadays the general annual catch reaches 40,000 tons. It is well known that catching sturgeon fish began in this area long ago. AS far back as the middle of the seventeenth century, catches of sturgeon here reached 50,000 tons a year. There were rather big catches in the nineteenth- and the beginning of the twentieth centuries. However, due to the extremely high intensity of fishing around 1930, the catch of sturgeon decreased to 13,500 tons, and by 1946 to 4,900 tons. Owing to the accepted measures of preservation of the stock, the catch of these fish increased during the subsequent period, and in 1968 reached 11,600 tons. In the 1970s and 1980s the catch of sturgeon reached 20,000-25,000 tons, and black caviar production reached 2000 tons. The short period of sufficient stocks ended in the late 1980s, when there was a reduction in the catch. Within 15 years, the catch fell ten times, and in 2004 the catch of the sturgeon by fishermen of the Russian Federation in the Volga-Caspian basin was about 400 tons, including 153 tons of sturgeon fish caught for research purposes and reproduction. In these circumstances the preservation of sturgeon fish in Russia, and, in particular, on the Lower Volga, has become especially significant.