Species Composition and Distribution of Benthic Fishes in the Elittoral of the Northwestern Part of the Sea of Okhotsk in Summer

Abstract

Based on the materials of the trawl survey conducted at depths of 81–301 m in the northwestern part of the Sea of ​​Okhotsk in August–September 2013, the species composition and characteristics of bottom shelf fish’s distribution are described. On the shelf, 69 species were recorded, including 54 species from 11 families, among which Zoarcidae (19 species), Liparidae (17), Cottidae (7), Pleuronectidae (7), and Cyclopteridae (5) dominate in terms of the number of species and abundance. Two groups of fish were identified on the shelf: one is made up of species that prefer extremely low temperatures of the western Sea of Okhotsk cold lens (below –1°C), and some of them are found only within it’s range; the other includes the species that avoid it. The boundary between shelf and bathyal ichthyocenes passes through an isobath of 200 m. Depths of 150–250 m are populated by an ecotone community, in which a sharp transition from shelf to bathyal ichthyocene is observed.