Characteristic features of ecology of the Pacific saury Cololabis saira (Scomberesocidae, Beloniformes) in open waters and in the northeast Pacific ocean

The results of long-term studies of the spatial distribution, size composition, and spawning intensity of the Pacific saury Cololabis saira in open waters of the North Pacific Ocean and the northeastern part of the Pacific Ocean off the west coast of North America are presented. In the open waters of the Pacific Ocean, saury forms aggregations early in summer; intraseasonal changes in their distribution pattern have been identified. Migrations of Pacific saury stocks in the northeastern part of the Pacific Ocean were considered, and assumptions about their causes were made. The differences in the size composition of Pacific saury in different parts of the range are associated with the peculiarities of occurrence of favorable conditions for the formation of aggregations. Intensive spawning of Pacific saury in the northeastern part of the Pacific Ocean is observed in winter and spring, and that in open waters is observed in summer. The distribution of the early progeny of Pacific saury is associated with the systems of currents; its findings in the extreme northern regions in the 1980s are explained.