THE REGIMEN`S INFLUENCE ON THE SPAWNING MIGRATION RUN OF THE FISH`ES DIFFERENT ECOLOGICAL GROUPS TO THE VOLGA DELTA LOWER ZONE
In the article is contains the timing of the spawning migration run and the spawning analisis in the Volga River delta lower zone in the low water (2012 ) and middle water (2013 ) years. The lowering of the Caspian Sea`s level and the decreasing of the Volga spring runoff aren`t alone to a reduction in terms of the spawning bottom-lands flooding time and the combining the time and the breeding area for the mass fish species, but also a significant shift of the timing and nature of the pre-spawning migration run and the emigration of the spawners.