The East Sea Fisheries Research Institute of NIFS had analyzed the population rate of catch by set nets in Goseong and Yangyang, Gangwon Province and Uljin, Gyeongbuk for 20 years. The result showed that the emergence rate of warm current fish species- such as yellow tail, horse mackerel, spanish mackerel, etc.- surged for recent five years (’20-’24) compared to the past fifteen years (’05-’19). More specifically, the rate increased to 53% in Goseong, 64% in Yangyang, and even 90% in Uljin. 

In case of yellow tail population, the catch had increased steadily as it ranked no.1 in Goseong, the northernmost part of South Korea’s eastern coast, accounting for 21.6% of the catch by set nets. The analysis showed that the extended period to form the suitable temperature for yellow tail to live (from May-October to May-December) and expanded migration area (up to Goseong from exisiting Gyeongbuk) were behind the steady increase. 

As such, climate change-driven temperature increase made migratory fish in the East Sea further expand their migration coverage, bringing about changes in region-specific emergence fish species and dominant species.

Meanwhile, when the recent 5-year temperature changes were compared to the average water temperature(’05-’09), there was an outstanding change in the sea areas around Gangwon with an increase of 1.1℃, higher than the 0.7℃ increase in that of Gyeongbuk. 

This was because the isothermal lines (above 16℃) swiftly move northward to Gangwon sea areas due to persistently increasing volume of Tsushima Current coupled with increasing heat transfer from the atmosphere.