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The continuously lowering of stocks of sturgeon fishes in Russia testify that now natural populations of these fishes, are in a status of biological depression. This phenomenon attracting attention of the scientists not only in Russia, but also all over the world as sturgeon fishes are unique relict species, which have survived millions of years of evolution and have adapted to the quite various ecological conditions. Nevertheless, though stable against impact of quite different ecological natural factors, sturgeons have appeared completely defenseless to the anthropogenic factors: intensive, often scientifically not reasonable, catching both in rivers of spawning and in the sea; river damming, which has cut off sturgeons a way to natural breeding bottoms; pollution of water environment by industrial, agricultural wastes and household drains. Finally, replacement of natural reproduction by artificial one, technological stages of which are frequently so differ from the appropriate stages of sturgeon evolution in natural environment, that actually brings to nought all adaptive advantages, obtained by the fishes of this systematic group during their long period of phylogenesis. For the development of the appropriate strategy and plan of measures on conservation of biodiversity and sustainable use of sturgeons it is necessary to create permanently up-dated database, which will allow to provide in a real time with information on sturgeon species (including rare and endangered species), based on a variety of habitat areas and on specific sturgeon species and populations. Taking into consideration information on status of both sturgeon populations and also more small-sized taxonomic units and seasonal groups; all of them can be referred to rare and endangered species, and the inclusion of sturgeons in Appendices II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) testifies it. Status of Sturgeon Fishes at the
Species Reservoirs of the European part of Russia: Status of sturgeon populations in the Caspian Sea basin: Russian sturgeon (Acipenser guldenstaedti), starred sturgeon (Acipenser stellatus), great sturgeon (Huso huso), barbel sturgeon (Acipenser nudiventris), Persian sturgeon (Acipenser guldenstaedti persicus). Primary reasons of decrease in numbers of sturgeon fishes populations in the Caspian Sea basin are the following:
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