우리나라 연근해 고등어(Scomber japonicus)의 어황변동 특성(2008-2016년)

Abstract

The characteristics of fishing condition in 2008-2016 were investigated for reasonable resources management and precise fishing prediction of chub mackerel. The CPUE of purse seine fishery was 27.5 MT/haul in 2008 and 15.9 MT/haul in 2016 with decreasing trend. The proportion of chub mackerel catch according to regional sea was 64.0%, 18.0%, 9.8% and 8.2% in South Sea, Yellow Sea, East China Sea and East Sea, respectively. Annual mean folk length showed increased trend representing 28.8cm in 2008 and 30.5cm in 2016. The main fishing grounds of chub mackerel located in near Jeju Island and southern area of Yellow sea and northeast area of Tsushima Island. The center of fishing grounds were located in northern Jeju Island and around off western South Sea, and moved from west to east for last 10 year. Hotspot for catch could founded by 15℃ (10-20℃) isotherm which indicates between southwest area of Jeju Island and Northeast area of Tsushima Island. Thermal front or frontal zone play a important role to determine position of fishing ground. The optimal temperature for fishing is estimated 13.8-27.2℃ in SST with high seasonal variability and 13.5-16.9℃ in 50m depth with relatively low variability. Based on correlation analysis, fishing condition of chub mackerel in Korean waters was positively correlated with surface & 50m water temperature in South Sea and 50m water temperature in Yellow Sea, respectively.