The influence of oceanological conditions on the location of pelagic fish fishing areas in the Pacific waters of the Kuril Islands during cold 2017 and warm 2018

Formation of the surface structure mechanism of the South Kuril waters in the last two years has undergone significant changes. Therefore, the “cold” type of hydrological conditions prevailed in the South Kuril area during August-November 2017. The surface water temperature was below the norm by 1–2 °C. On the contrary, the “warm” type of hydrological conditions prevailed in the South Kuril area during August-November 2018 and the water temperature in the area under consideration was 1–3 °C higher than the average for many years. Saury fishing in 2018, as in 2017, began in the second decade of August on the peripheral fronts of the Ask eddy and continued here until the second decade of September. At the end of September, the fishing area formed in the southwestern part of the EEZ of the Russian Federation and, unlike last year, it remained until the beginning of the third decade of October. The “warm” type of hydrological conditions causes this duration of the fishery. Saury moved outside the EEZ in late October. Fishing for sardines and mackerel began in mid-July 2018 and was carried out on the northern periphery of the eddy A’. However, at the end of October, unlike in 2017, fishing here practically stopped due to a decrease in the temperature drops at the peripheral fronts of the eddy caused by the high temperature of the surface waters of the Oyasio current. In late October — the first half of November in 2018, mackerel and sardine fished in high-gradient areas of the Northern Subarctic Front (NSAF) close to the eastern and southern borders of the Russian EEZ. During fishing season 2018, in contrast to the previous year, schools of sardines and mackerel remained much longer in the economic zone of Russia