Состояние запасов, факторы внешней среды и эффективность воспроизводства популяции анчоусовидной кильки (Clupeonella Engrauliformis Borodin) в современных условиях

Abstract

Until the end of the XX century, anchovy sprat was the leading object of marine fishing in the Caspian Sea. At the beginning of the XXI century, there was a mass death of this species, as well as an outbreak of the number of mnemiopsis comb - a powerful consumer of feed zooplankton. There was a redistribution of keel clusters in the sea. The main part of the fishing stock of keels began to be distributed in the Middle Caspian Sea. The main object of marine fishing has become an ordinary sprat. In recent years (2015-2020), there has been an increase in the number of anchovy sprats. The materials of keel surveys also confirm the annual growth in the number of juvenile sprats. This paper presents the results of recent years of observations, shows the dynamics of the number and biomass of the population, the parent part of the herd, total fertility. The efficiency of spawning and the survival coefficients of the generation in early ontogenesis are shown. Environmental factors that have a direct impact on the formation of the anchovy sprat stock are described.