In recent years, the state of the Caspian roach reserves has been repeatedly discussed at different levels and sites. The number of this species is declining, catches are falling. Based on the instructions of the Volga-Caspian Scientific and Commercial Council of the Volga-Caspian Fisheries Basin, a draft comprehensive program for the conservation and restoration of roach stocks is being developed, in which it is planned to consider the imposed restrictions on fishing, the possibility of artificial reproduction, the need for in-depth monitoring of the population. Observing negative trends for a number of years, understanding the social significance of the species, immediate emergency measures are needed to preserve and restore the Caspian roach in order to avoid its loss.
The work presents the assessment of unaccounted withdrawal of fluvial anadromous and river fish species in the inland fisheries of the Astrakhan region, which is composed of despoliations of commercial catches, poaching and amateur fishing. Methodology decisions that are developed at the CaspNIRKh were the calculation basis of the unaccounted fishing withdrawal and assessment of the impact of amateur fishing on the aquatic bio-resources. The article shows the evaluation method of volumes of poaching fish withdrawal. It is found that the main objects of the unaccounted withdrawal were more valuable fishing species (roach, pike perch, catfish, carp, bream, and pike). The despoliation of commercial catches made 28% on the average. One year minimum poaching fish withdrawal in the region, using the example of 2015, was 7.94 thousands of tones and 19% from commercial catch, and 20-30% of fish catching, harvested by the amateur fishing. The work presents the pressing of unaccounted withdrawal of fluvial anadromous and river fish species on stocks. On the back of decrease of stocks and commercial catches of fluvial anadromous and river fish species, development scales of all directions of unaccounted withdrawal in the Astrakhan region disturb all preconditions for reconstruction and growth of fish number.
In 2018, in the bottom fauna of the Caspian Sea, single specimens of a previously unknown species of polyhaetes were discovered. Since 2019, pelagic larvae of this species have been recorded in zooplankton samples. These worms are also found in the nutrition of migratory and semi-migratory fish species. According to morphological features, this polychaete species is identified as Marenzelleria arctia , an Arctic species dominating in the Gulf of Finland and probably invaded the Caspian along the Volga-Caspian invasion corridor.
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