The article analyzes differences in the vertical structure of waters and hydrochemical parameters at three oceanic stations in the northeastern Pacific. Data on the species composition of mesopelagic fishes, squids, and gelatinous organisms making diurnal vertical migrations to the epipelagic zone are given. Differences in their ratio and size composition at different stations are analyzed. The species ratio and size and total biomass of micronekton and macroplankton change in the southwestern direction, which is primarily determined by the variability of the oceanological characteristics of the subsurface layer.