Spatial distribution and biological characteristics of the Okhotsk Sea Pollock in the winter-spring period

Abstract

The data on the biology and fishing of pollock in the northern part of the Sea of Okhotsk collected during its monitoring on fishing vessels in the winter-spring period 2001–2021 are analyzed. Analysis of the dislocation of the fishing fleet makes it possible to trace the formation and distribution of pollock clusters. A significant amount of the collected material made it possible to characterize the dynamics of gonad maturation and the change in the size and age structure of individuals in commercial subzones. Pollock fishing usually began in the Kamchatka-Kuril subzone and partly in the North Okhotsk subzone in the area of the Swan Upland, with gradual development northward into Shelikhov Bay, Pritaui district and the North Okhotsk shelf. The basis of the catches was pollock at the age of 5–8 years at the pre-spawning stages of the development of sexual products. By-catch of juveniles varied from 0,5% (2009) to 63,5% (2018), averaging 23,5% in the North Okhotsk subzone, 34,8% in the West Kamchatka subzone and 15,5% in the Kamchatka-Kuril subzone.