Distribution of Sea-Bed Waste in the Northeast and Southwest Seas of Jeju

This study is a basic study for the management of major commercial fishing grounds in Korea. To this end, this study analyzed the types, characteristics and density distribution of sea-bed waste through a survey of bottom trawl in the northeast and southwest seas of Jeju for total 6 years from 2019 to 2024, and investigated the relationship between the appearance of sea-bed waste and the fishing industry. A total of 199 sea-bed wastes were collected in the total survey area of 6.3km². Out of them 135(68%) were fish traps, followed by 25(13%) living wastes and 15(8%) nets, 11(5%) eel traps, 8(4%) ropes and 5(2%) long lines. By type of weight density, waste net was collected at the highest rate at 266.7kg/km² at 229 sea area in July, followed by fish trap at 126.3kg/km² at 223 sea area in April, long lines 64.7kg/km² at 239 sea area in June, eel trap at 8.8kg/km² at 240 sea area in June, rope 7.9kg/km² at 223 sea area in April. Based on the survey area, the season with the highest distribution density of sea-bed waste per unit area(km²) by period was April, when fish traps and long lines were the highest at 200pcs/km², 600kg/km², 12.5pcs/km² and 25kg/km². Nets and eel traps were the highest at 5.3pcs/km², 227.4kg/km², 10.5pcs/km² and 6.3kg/km² in July. Fish traps were the highest at 38.5pcs/km², 146.2kg/km² in October. Therefore, fishing gears such as fish traps, nets, and long lines, which occupy the majority of sea-bed waste collected, originate from the fishing operation conducted in this sea. In addition, efforts are needed to strengthen the responsibility of fishermen by implementing a real-name fishing gear system and a fishing gear-buoy deposit system to manage the history of fishing gear used.