M. N. Gorokhov’s research while affiliated with All-Russian Research Institute Fisheries and Oceanography and other places

The article presents an analysis of the boundaries of the Volga pre-estuarine forbidden space in retrospect and in the present period. The dynamics of the area of the Volga pre-estuary forbidden space is shown, which over the last century has decreased by more than 10 times. Most of the water area of the Volga pre-estuary forbidden space is currently located on land. Reason: drop in the level of the Caspian Sea and a decrease in the volume of Volga runoff. Using the example of a separate northwestern section of the delta and delta front of the river The Volga River clearly shows how the coastline of the Caspian Sea and, accordingly, the protective zone of the Volga pre-estuary forbidden space have changed. Taking into account the current water and fishery situation, the dynamics of the fall in the level of the Caspian Sea, proposals were made to update the northern boundary of the space, draw the coastline along the mark of 28.7 m BS and expand the protected areas.

The aim of the paper is an expert assessment of the quantitative, qualitative and species composition of IUU-fishing and their dynamics for 2017-2021. Analysis and synthesis of materials of ichthyologic examinations received from law enforcement agencies in the Volga-Caspian branch of “VNIRO” (“CaspNIRKh”). For the first time, an assessment of IUU fishing of sturgeon in the Caspian Sea for 2017-2021 was carried out. Quantitative and qualitative assessments of IUU-fishing, its species composition and their dynamics for 2017-2021 were obtained. The results of this study canbe used in predictive models of the dynamics of sturgeon stocks and in the analysis of the situation with the protection of these fish species in the Caspian Sea.

The silver bream Blicca bjoerkna and the small-sized common bream Abramis brama are characterized by external similarity, which contributes to manipulations with the substitution of one species (common bream) by another (silver bream) when taking into account the volume of industrial fishing in the Astrakhan region. This is due to the fact that in the period of spring fishing season during common bream spawning migration, the share of non-commercial common bream in commercial catches increases (to 20–30 %), the catch of which is limited in accordance with the Fishing Rules. In order not to exceed the allowable volume of by-catch of non-large common bream, fish producers register en masse catches of small-sized bream as a catch of silver bream, which causes significant damage to common bream fish stocks through oversampling of first-time maturing individuals of the population. In recent years, the share of non-commercial common bream recorded as a silver bream in May alone is 13–28% of its official catch during this period. In order to reduce the catch of first spawning common bream producers of non-commercial length on the water bodies of the Astrakhan region in the period from April 21 to May 20, it is recommended to introduce a ban on industrial fishing of silver bream.

The main area of pike habitat and fishing is the avandelta of the Volga River. Pike fishing is conducted by passive fishing gear - mainly by secrets, to a lesser extent by nets. The main part of the pike catch traditionally falls in the spring period, when it forms pre-spawning and spawning clusters. Since 2010, official pike catches have been declining in March and April, due to an increase in illegal seizures. Pike caviar, due to its high nutritional qualities and demand among the population, has a high cost, which contributes to the massive concealment of commercial catches and poaching. Over the past two decades, the biological indicators of pike in the Volga River delta have undergone changes. Based on long-term data, there was a decrease in the age range, an increase in the proportion of younger age groups, a decrease in the proportion of females in the sexual structure of the population, average age, length and weight of pike. At the same time, the size and weight indicators of the same-aged pike individuals are quite stable. The main reason for the ongoing negative changes is the purposeful high commercial withdrawal of females in the pre-breeding and spawning periods. The scale of the total pressure of illegal industrial, poaching and amateur fishing, according to expert estimates, is comparable to the amount of official catch recorded by fishing statistics. To reduce the catch of spawning females for the first time, it is recommended to increase the minimum fishing length of the pike.

За 125 лет КаспНИРХ прошёл путь от одной из первых в России ихтиологической лаборатории до современного научно-исследовательского учреждения — флагмана рыбохозяйственной науки на Каспии.

The nature and methods of fishing become extremely important in inland waters with a limited raw material base and sharply changing reproductive capacity of fish herds under the influence of habitat. Currently, 19 species of semi-passable and river fish are used in the Astrakhan region. All these species live in a single water area and practically do not create local single-species clusters. The modern resource base of semi-navigable and river fish, on which industrial fishing in the Astrakhan region is based, is limited. Stocks of a number of fish species are declining – roach, tench, pike. Stocks of others are stagnating at a low level – bream, catfish. At the same time, the annual increase in fishing intensity due to the commissioning of new fishing sites does not compensate for the decrease in commercial catches, which indicates the tense state of the fishing resource base in the Astrakhan region.

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.