우리나라 연근해의 살오징어 어업관리를 위한 생물경제학적 연구

Abstract

Korea’s total coastal fisheries production in 2022 totalled 887,239 tonnes, worth KRW 436.9 billions. Common Squid production, among others, was 36,549 tonnes and worth KRW 305.9 billion, corresponding to 4.1% of the total output and to 7.6% of the total value. With the aim of continued reproduction and protection of this commercially important species, Korea has introduced various management tools, including total allowable catch (TAC), closed seasons, and length regulations. The production of Common Squid reached a peak at 252,618tons in 1996 and maintained a stable level of about 200,000 tons until the mid-2000s. The production, however, continues to decline thereafter. The previous studies on the species had focus on evaluating the level of technical efficiency in the fishery or documenting fluctuations in abundance depending on water temperature, etc. While some of the recently published studies assessed the Common Squid stock, they tend to depend solely on domestic catch data and did not even consider the stock’s migratory nature and behavior. For this reason, this study incorporated catch and effort data by each Common Squid fishery from the neighboring nations of China and Japan that share the stock as well as from domestic sources, into the stock assessment. And this study also conducted a bio-economic analysis of the stock based on the results of the stock assessment and made policy recommendations to better manage the Common Squid stock. First, the study looked into long-term catch and effort data statistics from Korea, China, and Japan and employed CMSY as a stock assessment model. Second, to identify the level of business performance by each fishery type subject to the Common Squid TAC, this study also identified the financial status of each fishery type and examined production costs, along with net profits by each fishing vessel and fishery type. Third, based on the profits equivalent to current TAC allocation levels, the study figured out changes in profit under different scenarios where TAC allocations are expected to reduce. This is because while TAC allocation reduction is required due to the stock’s declining trends, business performances by each fishery type should be also taken into consideration at the same time. Lastly, this study made recommendations for sustainable management strategies for Common Squid in Korea’s coastal waters, taking into account business performances by fishery types as well. It was confirmed through the assessment that the size of the stock is on the decline and that the stock in 2020 was at a level lower than bMSY, which is classified as ‘overfished (CMSY)’. It was also found that the TAC allocation reduction percentage where net profit becomes zero by fishery type was 10 % for large-scale pair trawl fishery, 35% for large-scale trawl fishery, 25% for East area mid-scale trawl fishery, 80% for large-scale purse seine fishery, 30% for the offshore jigging fishery, and 45% for offshore gill net fishery. These findings suggest that the TAC allocation system for those participating in the Common Squid fishery be operated more effectively. As a conclusion and for the better management of the Common Squid stock, this study suggested the sharing of Common Squid catch and effort data between Korea, China, and Japan, introduction of ITQ, improvement of the existing TAC allocation system, and reduction of fishing efforts for the stock and reinforcement of fisheries Monitoring, Control, and Surveillance (MCS).