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Аннотация. В результате выполненных траловых съемок эпипелагиали российских вод западной части Берингова моря, тихоокеанских вод Командорских островов, южной, западной и восточной частей Охотского моря определены численность и биомасса всех представителей нектона и макропланктона. Выявлены особенности пространственного распределения массовых представителей эпипелагического нектона и медуз, получены их количественные оценки, определен уровень численности посткатадромной молоди и нагуливающихся неполовозрелых лососей, оконтурены основные скопления посткатадромной горбуши в открытых водах Берингова и Охотского морей. В результате съемок получены новые данные о размерно-весовом составе скоплений, собраны материалы для анализа пространственной дифференциации различных региональных групп горбуши на обследованных акваториях.

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Spatial distribution, abundance and biomass of fish species, cephalopods and jellyfishes are determined in the epipelagic layer on the data of trawl surveys conducted with RV TINRO and RV Professor Kaganovsky in the Pacific waters at Kuril and Commander Islands, western Bering Sea, and Okhotsk Sea in 2022. Modern state of the nekton communities is considered, in particular the state of pink and other species of pacific salmon in summer and autumn seasons. New data on the size-weight composition of pacific salmon are presented; materials for spatial differentiation between their regional groups of pink salmon are available.

Modern technique of counting pink salmon juveniles in trawl surveys by two research vessels simultaneously makes it possible to cover the surveyed area in a short time that excludes repeated counts of actively migrating fish at adjacent transects. Such survey in the fall of 2022 was conducted jointly by RV TINRO and RV Professor Kaganovsky. The main aggregations of pink salmon in the offshore areas of the Bering and Okhotsk Seas were accounted that guaranteed reliability of the primary materials for prediction of the pink salmon return and catches in 2023. Two regional groups of pink salmon were separated in the mixed aggregation of juveniles in the Okhotsk Sea using the method of EM-clustering; the ratio of «northern» and «southern» complexes of their local stocks was determined as 55 : 45 %. The total number of pink salmon was assessed as 0.94 ∙ 109 ind. in the Bering Sea and 2.70 ∙ 109 ind. in the Okhotsk Sea. Expected return of pink salmon in 2023 was preliminary estimated as 200 ∙ 106 ind. for the Bering Sea and at least 270 ∙ 106 ind. for the Okhotsk Sea.