참조기 어업의 생물경제학적 분석: LBB 모델을 이용한 포획금지체장 효과분석을 중심으로

Abstract

The aim of this study is to evaluate the stock status of the Yellow Croaker (Larimichthys polyactis) and to analyze changes in fishing profits based on catch size limit regulation. The Yellow Croaker is one of commercially significant species in Korea, with market prices closely tied to catch size. For the stock assessment, a length-based bayesian model (LBB) is employed. The LBB model indicates that the asymptotic length (Linf) and the optimum fishing length (Lopt) of the Yellow Croaker are 41.12 cm and 28 cm, respectively. Moreover, the estimated ratio of the current exploited biomass relative to the unexploited biomass (B/B0) is 0.49. In particular, the estimated biomass as of 2022, is 68% of the biomass that can produce maximum sustainable yield. Based on these findings, a management analysis is conducted to evaluate the potential impacts of increasing catch size limit regulations. The bioeconomic analysis projects the net present value (NPV) of a total allowable catch (TAC)-based Yellow Croaker fishery next 30 years. The analysis revealed that, although short-term revenues initially decline due to reduced catches associated with the implementation of prohibitive size limits, long-term revenues exhibit a substantial increase. These results can be attributed to enhanced catches driven by reproductive the Yellow Croaker resource recovery and large market price variation by reference size. Additionally, the NPV of the Yellow Croaker fishery improves as the catch size limit regulation becomes more restrictive. These findings suggest that increasing the catch size limit regulation is essential for the effective management of the Yellow Croaker fishery. Targeting larger fish sizes not only supports the recovery of fishery resources but also enhances economic efficiency.