Journal / Archives
УДК 597.553.2-154.343 DOI: 10.15853/2072-8212.2018.48.62-69Download the full article
Assessment of regional origin and distribution of hatchery pink and chum salmon on results of otolith marking in the basin of the Sea of Okhotsk in the fall period of 2016 .
Otolith structures of juvenile pink and chum salmon from trawl catches of complex surveys provided in October–November of 2016 by R/V “Professor Kaganovsky” were examined. The otolith samples for the analysis were collected from 600 pink salmon individuals and 1150 individuals of chum salmon. Obtained results allow to identify hatchery marked fish in mized catches. In the total there were 15 (2.5%) pink and 50 (4.3%) chum salmon individuals revealed with otolith marks of different salmon hatcheries (SHs) of Russian Far East and Japan. Structure of hatchery juvenile release in the Sea of Okhotsk basin was analyzed. The highest number of juvenile pink and chum salmon was released from the Shs of Sakhalin, and the leader in the release of marked juvenile pink was Sakhalin cluster of the hatcheries, and of chum salmon – the cluster of Japan. It was figured out based on the analysis of the otoliths of juvenile pink salmon from the Sea of Okhotsk, that the percental contribution of fish from different regions into the catches is generally fits structure of the release of marked juvenile pink salmon from the SHs of Russian Far East and Japan. In the ratio between marked Russian and Japan juvenile chum salmon in the Sea of Okhotsk juvenile aggregations the part of Russian hatcheries was first time ever higher than the part of the hatcheries of Japan, what can indirectly evidence in favour of increasing survival of marked fish from Russian SHs and better quality of the marks.
It was figured out during analysis of the distribution of marked juvenile pink salmon in the west part of the Sea of Okhotsk, that the sites of the catches of marked pink in most cases coinsided with the sites of increased density of pink salmon underyearlings. Analysis of distribution of marked juvenile chum salmon in the waters of the sea has revealed that in 2016 there was rather obvious spatial dissociation between feeding juvenile salmon from Russian and Japan SHs.