Trudy VNIRO

5–20

Authors: Sidorov L.K., Pereladov M.V., Labutin A.V.

The article presents the results of underwater video observation of conical crab pot in vivo. The behavior of the king crab in the zone of action of conical crab pot is analyzed. Using the video recording method, it was possible to accurately determine the ratio of individuals that entered the pot to the total number of individuals that appeared, to track the movement of crabs depending on the change in current. Based on the data obtained, the behavioral algorithms of individuals are described. It was shown that the location of the bait and the design features of the pot affect the catch efficiency. In order to entry into the pot it was necessary to make 2.91 attempts on average. In 93.8% of cases, the appearance and entry of a pot against the current was recorded. The average crab appearance rate was 24.5 ind./h, and the entry rate into the pot was 7.9 ind./h. In search of bait, the crab mainly moves in small segments of 2–3 meters, developing a speed of 0.11 to 0.38 m/s, an average of 0.21 m/s, with subsequent stops to identify the direction of the smell source. A new method is proposed for estimating the density of individuals of the red king crab in the study area based on the speed of catching the pot. The derived formulas for calculating the density make it possible to standardize the data and use the catches of pots with different time intervals of being under water. The table is proposed for the transition of the pot catch to the population density of the red king crab.

38–49

Authors: Voytenko O.V.

VNIRO, 17, V. Krasnoselskaya

77–83

Authors: Boltnev E.A., Torgun P.M., Boltnev A.I.

A histological analysis of the testes, whose tissue samples were taken from fresh corpses of 18 sea otter aged from one month to two years in the period of their mass death on Bering Island in 1991–1995, was carried out. Testes were fixed in liquids of Shtiva, Buena. The material was embedded in paraffin. Sections 4–5 µm thick were stained with hematoxylin-eosin, Heidengain’s azan, according to the method of trichrome and tetrachrome-CHIC. Morphometric characteristics were used as indicators of the development of spermatogenic epithelium: using a screw eyepiece micrometer, the diameter of the seminiferous tubules, the diameter of the nuclei of spermatogenic cells were measured, the area of the nuclei of sustentocytes and interstitial endocrinocytes was determined, and the number of stenttocytes in a single cross section of the seed canal was determined. Studies have revealed active spermatogenesis in the testicles of sea otter at the age of two years. In these sea otters, the diameter of the seminiferous tubules reaches a maximum; the convoluted seminiferous tubules contain all spermatogenic cells, including spermatozoa. Sustentocytes and interstitial endocrinocytes are characterized by signs of high functional activity.

104–111

Authors: Lukin A.A., Lukina J.N.

Fishes in Subarctic lakes are highly demanding to the water quality and pollution results in organism response that allows to use it as a test objects reflecting state of water quality. Ichthyopathologies cause transformations of population and ichthyofauna under anthropogenic impact. The development of Kola Peninsula resulted in pollution of water bodies with wastewater from mining enterprises containing heavy metals, surfactants, petroleum products, sulfates and others. Lake Bolshoi Vud’yavr that is located in the center part of the Khibiny mountain massif and can be considered as a man-made technogenic water area under multifactorial chronic pollution for decades. Ichthyofauna of the lake in the 1930’s, consisted of 6 species: brown trout, аrctic char, whitefish, grayling, burbot, nine-spined stickleback. The sewage resulted in almost complete disappearance of fish in the lake, excepting Arctic char, which currently dominates the ichthyofauna. Water quality assessment was carried out on the basis of histological analysis and revealed changes in the gills, liver and kidneys, indicating metabolic disorders, weakened immunity, the development of functional disorders and the mobilization of compensatory mechanisms. Most of the morphological changes should be regarded as the long-term consequences of chronic sublethal exposure to toxicants, which can cause a reduction in life expectancy, early maturation or infertility. However, a number of histopathologies testify to acute reaction of fish organism and make it possible to assume that there are sporadic local discharges of pollutants.

150–171

Authors: Kovacheva N.P., Litvinenko L.I., Saenko E.M., Zhigin A.V., Kryahova N.V., Semik A.M.

It provides an overview of the cultivation of artemia in the retrospective and the current aspect in the world and in Russia. The analysis of literature data shows that the artemia cultivation develops in three main directions: obtaining nauplius by the method of incubation of cysts; extensive cultivation of basin and pond methods; intensive cultivation in open and closed water systems. It is shown that the most acceptable type of aquaculture in the conditions of Western Siberia is the introduction of naupliius into natural salt water bodies during the period of biomass decline in the local artemia population and the production of additional cysts. Intensive cultivation of artemia in open and closed water supply systems involves the cultivation of crustaceans with high density in special tanks (basins) with increased water exchange and feeding artificial feed. The basic principles for the production of artemia in temporary salt farms, as well as the main components in the organization of cultivation are presented. In addition to the development of scientific biological and technological foundations of artemia aquaculture, it is indicated that improvement of the regulatory legal regulation of this field of activity is necessary. In particular it required changes and additions to a number of regulatory legal acts in the field of aquaculture. Attention is drawn to the need to develop preventive measures to control the activities of enterprises in the aquaculture of artemia in Russia.

188–199

Authors: Shindavina N.I., Nikandrov V.Ya.

The studуwas carried out in Federal Selection and Genetic Center of Fish Breeding in 2016–2017 (Ropsha, Leningrad region). Females and males of rainbow trout of mutant golden color at the age of 2+ were kept in different light and temperature conditions for 9 months before their maturation. Females and males were compared in weight and body size, and reproductive features. An individual assessment of females for embryo survival was carried out. The significant effect of water temperature on the growth rate of fish, the maturation of females, fecundity and the size of eggs was revealed. It was found that intensity of the body golden color and the carotenoid pigmentation of the eggs depends on the light. Moreover, females that were kept at low water temperature and low illumination intensity for a year were characterized by the lowest survival rates of embryos. Thus the intensity of illumination and optimization of the temperature regime in the development of biotechnology for breeding of rainbow trout of golden color should be taken into account.

206–220

Authors: Orlov А.М., Benzik А.N., Vedishcheva Е.V., Gafitsky S.V., Gorbatenko К.M., Goryanina S.V., Zubarevich V.L., Kodryan К.V., Nosov М.А., Orlova S.Yu., Pedchenko А.P., Rybakov М.О., Sokolov А.М., Somov А.А., Subbotin S.N., Taptygin М.Yu., Firsov Yu.L., Khleborodov А.S., Chikilev V.G.

Oceanographic, planktonic, trawl and acoustic surveys were conducted in the Chukchi Sea in August 2019 at the research vessel “Professor Levanidov”. The hydrological and hydrochemical regime was formed under the influence of the spread of Pacific waters coming through the Bering Strait; East Siberian desalinated waters — from the west along the coast and to the north of Wrangel island; and waters of Arctic origin. North of 73°30′N, waters of Atlantic origin with characteristic temperatures higher 0 °C and salinity over 34.5‰ were observed at the depths mainly from 180 m to the bottom, which were clearly traced in the distribution of bottom temperature, salinity and hydrochemical characteristics. The oxygen saturation of water in the surface layer within the entire studied area exceeded 100%, the maximum values — in the pycnocline layer (158%). The processes of photosynthesis were limited by mineral nitrogen, the onset of summer was evidenced by its minimum in the surface layer. Mesoplankton biomass was high with predomination of chaetognaths and copepods, euphausiids were second in rank; in the southern part of the sea biomass was twice as high as in the north. In the northern part, there was an intense phytoplankton bloom, a large number of nauplias and copepodites of the early stages of development, which formed a spring complex. In the southern part, low concentrations of phytoplankton observed, copepods were represented by older age groups, which is typical for the spring-summer period. The catch was dominated by the Tanner crab, accounting for about 50%. Sea stars and the brittle stars were of secondary importance, with polychaetes, sponges and gastropods to a lesser extent. 44 species of fish were found in the catches, and representatives of the families Cottidae, Zoarcidae, Liparidae, Gadidae, Pleuronectidae, and Agonidae dominated. The biomass of large walleye pollock was 890 thousand tons, that of polar cod 117 thousand tons, and Bering flounder 42 thousand tons. According to acoustic data, the abundance and biomass of pollock within the survey area was 242 million inds. and 398 thousand tons, polar cod — 9349 million inds. and 206 thousand tons, respectively. The daily ration of a large pollock varied from 3.4% to 4.7%, and that of polar cod from 2.5 to 9.4% for a different-sized fish. Of the marine mammals, the grey whale was most often found near the Bering Strait, while walruses and polar bears were observed in the northern part of the sea.